Experiments have shown that the motion of light(photons) does not depend on the motion of the source of the light at the moment of the emission.
There are many experiments confirming this, and one of them was conducted in 1964 by Torsten Alvager and his colleagues.
From the results of the experiments that are conducted, we have concluded that the motion of the source of the light does not affect the motion of the light that the source will emit, like the figure A example shows.
In the figure A I have tried to depict in one picture what the findings of the experiments are showing, which is that the motion of light is always the same regardless of the motion of its source.
The figure A shows that regardless of the motion of the light source at the moment of the emission, the light wave will move always at the same speed while traveling towards the two humans and will move from the one human to the other always at the same time!!!
Figure A. The light (photons) will move always in the same way, and will move from the one human to the other
always at the same speed, regardless of the motion of the light source at the moment of the emission.
always at the same speed, regardless of the motion of the light source at the moment of the emission.
What the findings of the experiments are actually showing is what we will see on the example in the figures B & C.
Suppose that there are two humans stationary on the surface of the Earth(figure B,a), and a source of light, the red light source, is also stationary on the surface of the Earth, and they are arranged like we see in the figure B,a.
Another source of light, the green light source, is moving towards the red light source and the two humans, as we see in the figure B,a.
Figure B,a. The green light source is moving towards the red light source with a direction towards the humans.
When the green light source is next to the red light source(as we see in the figure B), each light source will emit light with a direction towards the two humans.
Two waves of light will be created, one by the red light source and another one by the green light source(figure C).
The two light waves which are emitted by the two light sources will move exactly the same while traveling towards the two humans, as we see in the figure C!!!!!
The two waves of light practically being always next to each other, as we see in the figure C!!!
But, the two sources will not stay next to each other(figure C)!!!
The two sources of light(red & green light source) were next to each other when they emitted the light(figure B), but they will not stay next to each other(figure C) because they are in relative motion with each other, and the one source will be closer to the light waves that are moving away from the sources!!!
What we see in the figure C we will use it to reveal the anisotropy of the speed of light!!!
On the figures C we see that the two waves of light which are emitted by the two sources will move exactly the same
Figure B. When the green light source is next to the red light source, both sources will emit light towards the humans.
Two waves of light will be created, one by the red light source and another one by the green light source(figure C).
The two light waves which are emitted by the two light sources will move exactly the same while traveling towards the two humans, as we see in the figure C!!!!!
The two waves of light practically being always next to each other, as we see in the figure C!!!
But, the two sources will not stay next to each other(figure C)!!!
The two sources of light(red & green light source) were next to each other when they emitted the light(figure B), but they will not stay next to each other(figure C) because they are in relative motion with each other, and the one source will be closer to the light waves that are moving away from the sources!!!
Figure C. The two light waves that are emitted by the two sources are moving towards the humans.
What we see in the figure C we will use it to reveal the anisotropy of the speed of light!!!
On the figures C we see that the two waves of light which are emitted by the two sources will move exactly the same
regardless of the motion of their source!!!
The fact that the light always make the same motion regardless of the motion of the source, is actually the reason why there
is anisotropy of the motion of light relative to its source!!!!
But, in order for the anisotropy to be revealed, we must use an example with the sources emitting light towards all directions, meaning emitting a circular or spherical light wave!!!!!!
On the example in the figure C it's not so easy to see the anisotropy of the speed of light.
The anisotropy of the speed of light is revealed when the sources emit light towards all directions, so in the next examples we will find why what we see in the figure C leads to the acceptance that there is anisotropy of the speed of light!!!!!!!!!
Next, an extremely important realisation.
Suppose that somewhere(anywhere, it doesn't matter where) there are two sources of light(point sources) that are moving towards each other.
These are the red light source and the green light source(figure D,a).
The sources are in relative motion with each other at constant relative speed and both sources are in an inertial reference frame.
The sources currently do not emit light.
At some point the red light source and the green light source are next to each other(figure D).
When the two sources of light are next to each other(figure D), each source will emit light towards all directions.
After the emission of the light the sources are moving away from each other because their relative motion continues.
Two waves of light will be created, one from the light emitted by the red light source and the other from the light emitted by the green light source(figures E & F).
( The waves will be "three-dimensional waves" or in other words "spherical waves" because they will from an expanding sphere since the sources emit light towards all directions, but of course in the figures E & F we see "two-dimensional waves" or in other words "circular waves".
Instead of ''waves of light'' we can call them ''expanding bubbles of light'' or ''expanding bubbles/groups of photons'' since the sources have emit photons towards all directions)
The two light waves will expand with exactly the same way(figures E & F)!!!!
Not only the motion of the photons emitted by the two sources will not depend on the motion of the light sources, but moreover, the photons which are emitted by the two light sources will make identical motion, and that's why the two light waves will expand in exactly the same way(figures E & F)!!!!!!!
In other words we can say that there will be created two light waves which will be stationary relative to each other!!!
So, there are two light waves which expand in exactly the same way, and also there are two light sources which are in relative motion with each other, and here is the important realisation:
There are two possibilities:
First possibility(figure E): Only the one of the two sources will be at the hypothetical centre of its own light wave.
Second possibility(figure F): Both light sources will not be at the hypothetical centre of their own light wave.
The possibility of having both light sources to be located at the centre of their own light wave does not exist!!!
We cannot have both the red light source and the green light source at the centre of their light wave!!!
It doesn't matter where this example/experiment is taken place in the Universe, and it doesn't matter if one or both sources are making linear motion or if they revolve around something!!!
Only the one of the two light sources can be at the hypothetical centre of its own light wave!!!
The other possible reality is that both light sources will not be at the centre of their own light wave, but there cannot be both light sources at the centre of their own light wave!!!!!!!
Why???
Because the photons that the two sources have emit will move exactly the same and the two light waves will expand with exactly the same way(figures E & F), but the two light sources will move away from each other because they are in relative motion with each other!!!!
The two sources were next to each other when they emitted the light(figure D), but they will move away from each other because their relative motion continues!!!
Let's focus on the case which is depicted in the figure E, meaning in the case where the one of the two sources is at the centre of its own light wave.
The two sources are in relative motion with each other at constant relative speed and both sources are in an inertial reference frame, meaning that each source considers itself as being at rest, as stationary!!!
But even though this happens, even though both sources are in an inertial reference frame, the motion of the light waves relative to the two sources is not the same for the two sources(figure E), because the red light source is at the centre of its own light wave but the green light source is not at the centre of its own light wave!!!
Let's see things from the point of view of the two sources(figure E):
Let's see things according to the red source's reality:
The red source(figure E) considers itself as being stationary and it "says" that the green source is on the move, therefore, if the red source is at the centre of its own light wave it is something acceptable because it is stationary, and if the green source is not at the centre of its own light wave it is also something acceptable because the green source is on the move relative to the red source!!!
Now, let's see things according to the green source's reality:
Also the green source(figure E) considers itself as being stationary and it "says" that the red source is on the move, but even though the green source considers itself as being stationary it is not at the hypothetical centre of its own light wave, and the red source which suppose to be on the move it is at the hypothetical centre of its own light wave!!!
Therefore, the reality for the green source is totally different than the reality for the red source, even though both sources are in an inertial reference frame!!!
Let's focus on the case which is depicted in the figure F, meaning in the case where both sources are not at the centre of its own light wave.
The two sources have emit light towards all directions, but as the light is moving away from the sources, the distance between the sources and the light wave is not the same towards all directions, and this applies to both sources(figure F)!!!
As the photons that each source has emit are moving away from the source, some photons are closer to the source and some photons are farther away from the source, and this applies for both sources(figure F)!!!
So,we have a case where both sources consider themselves as stationary because both are in an inertial reference frame, but as we see in the figure F, for both sources the distance between the source and the wave is not the same towards all directions, meaning that for both sources there is anisotropy of the speed of light!!!!!!
The other possibility is that there will be anisotropy of the speed of light for only the one source, in the case where the other source is at the centre of its own wave(figure E)!!!
But, the possibility to have isotropy of the speed of light for both sources does not exist because the possibility to have both sources at the hypothetical centre of their own light wave does not exist!!!!
The figure E depicts the case where the one of the two light sources is at the hypothetical centre of its own wave of light.
This is the one possibility, and the other possibility is that both the red light source and the green light source will not be at the hypothetical centre of their own light wave(figure F)!!!
On the figure E we see anisotropy of the speed of light for the one light source.
In the case where both light sources are not at the centre of their own light wave(figure F), this means that there is anisotropy of the speed of light for both sources!!!
The possibility to have both sources at the centre of their own light wave, simply does not exist!!!
The photons that consist the two waves of light will make identical motion(figures E & F)!!!
There will be created two waves of light that will expand with exactly the same way(figure E & F)!!!
In other words we can say that the two light waves will be stationary relative to each other!!!
But, since the two sources of light(red & green light source) are in relative motion with each other, only one of them can be at the hypothetical centre of the light wave that it will emit(figure E)!!!!
This means that for the source that is not at the hypothetical centre of its own light wave we must say that there is anisotropy of the speed of light relative to this source, which is the green light source on the example in the figure E!!!
Isotropy of the speed of light relative to its source exist only for the source which is at the hypothetical centre of its own wave of light, which is the red light source on the example in the figure E!!!!!!
In order to say that the motion of light that a source has emit is isotropic relative to its source, the light that this source has emit must move in the same way relative to its source towards all directions, meaning that all the parts of the light wave must be at the same distance from the source!!!
This means that when we don't have the same distance between the source and the light wave towards all directions, meaning that some parts of the light wave that the source has emit are closer to the source and other parts of the light wave are farther away from the source, this is anisotropic motion of the light relative to this specific source, which is a source that is not at the hypothetical centre of the light wave that it has emit!!!
We can say that there is isotropy of the speed of light relative to a source only when the source is at the hypothetical centre of its own light wave!!!!!!
When a source is not at the centre of its own light wave, this means that there is anisotropy of the speed of light relative to this specific source!!!!!!
But, this anisotropy is not the result of a different motion of the light!!!!!!!
The light emitted by the two sources is making the exact same motion, and that's why the two waves of light which are produced by the two light sources are expanding with exactly the same way(figure E & F)!!!!!
But, in order to say which is the relative speed between the photons and the light sources we must focus on what the photons are doing in relation to the light sources, and not on if the photons emitted by the two sources are making the same motion!!!
If we say that there is anisotropy of the motion of light relative to its source, that statement does not contradict to the fact that the motion of light does not depend on the motion of the source!!!
The motion of light may not depend on the motion of the source, but we must say that there is anisotropy of the motion of light relative to its source when the distance between the source and the light wave that this source has emit is not the same towards all directions!!!
If we say that the time on the two sources(figure F) is running slower will not make any difference, because the fact that we care about is the fact that the source does not have the same distance from all the parts of the wave that it has emit!!!
This means that as the light is moving away from the source, some parts of the wave are closer to the source and some parts of the wave are farther away from the source, and whether or not the time on the source is running slower or faster does not changes that fact!!!
But, in a case where the one source is in front of the other in our line of sight at the moment they are emitting light, in order
to depict the light waves we will use only one wave, because the two light waves will move in exactly the same way!!!
The figure G depicts a situation like this!!!
This example will help you understand that the possibility to have both sources at the centre of the light wave does not exist!!!
So, as we see in the figure G,(a), two sources of light are moving towards each other.
It seems that they will collide, but actually the green light source will pass behind the red light source in our line of sight.
When the green light source is behind the red light source{ figure G,(b) } both sources will emit light towards all directions.
In the figure G,(b) we don't see the green source because it is behind the red source.
After the emission of the light the relative motion of the sources continues and the sources are moving away from each other.
Two waves of light will be created(figure G), one from each light source, but in order to depict the light waves we will use only one wave(figure G) because the two light waves will expand exactly the same!!!
On the figure G we see the one light source at the centre of the light wave because it depicts a similar situation with
the figure E.
This is the one possibility, and the other possibility is that both light sources will not be at the centre of the light wave, which is what will happen in most cases.
The possibility to have both sources at the centre of the light wave does not exist!!!
(Undoubtedly, two different waves of light will be created, one by each light source, but we will use one wave for the depiction because it is a depiction in two dimensions and at the moment of the emission of the light the two sources were the one in front of the other in our line of sight.
In three dimensions we must always use two waves.)
{In almost all the examples I will use depictions with the sources being next to each other in our line of sight at the moment they will emit light, in order to see the motion of the sources and the waves separately.}
Let's see what we will call isotropy & anisotropy of the motion of light relative to its source.
When we use the terms isotropy & anisotropy we refer to differences dependent on direction!!!
This means that if we talk about the motion of light relative to its source, we focus on the motion of light relative to its source towards different directions!!!
So, in order to say that the motion of the light that a source has emit is isotropic relative to the source, the light that the source has emit must move in the same way towards all directions relative to the source, and this is extremely important to understand because we talk about the motion of light relative to its source, and not relative to something else!!!
What does this mean???
Suppose that we have a light source that for a period of time does not emit light, for example a light bulb that is switched off, and at some point the source is switched on and emits a light wave towards all directions, meaning that it emits a spherical or circular light wave!!!
In order to say that the motion of the light wave is isotropic relative to its source, meaning to say that the relative speed between the source and the light wave is the same towards all directions, as the light wave is moving away from the source the distance between the source and the wavefront must be the same towards all directions, and this means that the source must be at the hypothetical centre of the wave of light that it has emit/produce(light source A on the figure H)!!!
If as the light wave is moving away from the source, the distance between the light source and the wavefront is not the same towards all directions, this means that we must say that the relative speed between the source and the light wave is not the same towards all directions, and this is anisotropy of the motion of the light wave relative to its source, and in this case the source is not at the hypothetical centre of the light wave that it has emit(light source B on the figure H)!!!
What is the situation that we see in the figure H??
We have a light wave moving away from its source towards all directions(figure H)!!!
The thing that we care about in order to say that there is anisotropy of the motion of the light wave relative to the source, is the fact that as the light wave is moving away from the source, we don't have the same distance between the source and the light wave towards all directions!!
If as the light wave is moving away from its source we don't have the same distance between the source and the wavefront towards all directions(as the light source B does in the figure H), this means that we must say that the relative speed between the light source and a part of the light wave is slower when this part of the wave is closer to the source, and the relative speed
Let's see the significant errors of the scientific community regarding the doppler effect in light, which have to do with the position of the light source in relation to the light waves!!!
When scientists want to explain the "doppler effect" in light, they use pictures which are similar with the following three figures(figures I,a - I,b - I,c).
Figure I,c.
Let's see an example using sound waves and the doppler effect in order to help us understand what I mean when I talk about the anisotropy of the motion of the wave relative to its source!!!
Suppose that we have a helicopter up in the air in two different scenarios.
In the first scenario that we see in the figure K, there is no relative motion between the helicopter and the air.
In the second scenario that we see in the figure L, there is relative motion between the helicopter and the air.
In both scenarios the engine of the helicopter is working and produces sound waves.
So, on the figure K we have the helicopter up in the air and its engine is running and it produces sound waves.
In the example that we see in the figure K, there is no relative motion between the helicopter and the air.
We can imagine that the helicopter is stationary relative to the ground and the wind is not blowing, or we can imagine that the wind is blowing and the helicopter is moving towards the same direction and with the same speed as the air does, but the important fact is that there is no relative motion between the helicopter and the air.
The helicopter, which is the source of the sound waves, will be at the hypothetical centre of the sound waves(figure K).
On the example that we see in the figure K, as the sound waves expanding and moving away from the helicopter(source), we have the same distance between the source/helicopter and the waves towards all directions, and this means that we will say that towards all directions the waves are moving away from the helicopter/source at the same rate/speed!!!
In the figure K, the relative speed between the helicopter/source and the sound waves is the same towards all directions!!!
In the figure K the motion of the sound waves is isotropic relative to the air, and it is also isotropic relative to the helicopter!!!
On the figure L the helicopter is up in the air, but in this scenario there is relative motion between the air and the helicopter.
There are various ways that we can imagine in order to have relative motion between the helicopter and the air.
We can imagine that the helicopter is on the move relative to the ground, or we can imagine that the helicopter is stationary relative to the ground but the wind is blowing, or we can imagine that both the helicopter and the air are on the move relative to the ground and that also the air and the helicopter are in relative motion with each other!!!
The helicopter, which is the source of the sound waves, will not be at the hypothetical centre of the sound waves(figure L).
On the example in the figure L, as the sound waves expanding and moving away from the helicopter(source), they don't move away from the helicopter at the same rate/speed towards all directions!!!
Towards the direction where the distance between the helicopter(source) and the sound waves is smaller we must say that the relative speed between the helicopter(source) and the wave is smaller, and towards the direction where the distance between the helicopter and the wave is larger we must say that the relative speed between the helicopter(source) and the wave is larger!!!
In the figure L, the relative speed between the helicopter/source and the sound waves is not the same towards all directions!!!
In the figure L the motion of the sound waves is isotropic relative to the air, but it is anisotropic relative to the helicopter!!!
As you can see on the figures K & L, I did not put an arrow on the helicopter to show that the helicopter is on the move because we don't care about whether or not the helicopter is on the move relative to the ground!!!
The thing that we care about is the whether or not there is relative motion between the air and the helicopter!!!
The motion of the sound waves is always isotropic relative to the air regardless if the air is on the move relative to the ground, but this did not mean that the motion of the sound waves is isotropic relative to the source!!!
Comparing the examples in the figures K & L, in both examples the motion of the sound waves is isotropic relative to the air, but the motion of the sound waves relative to the helicopter(source) is not the same on the two figures!!!
In the figure K the motion of the sound waves relative to the helicopter(source) is isotropic, but on the figure L the motion of the sound waves relative to the helicopter/source is anisotropic!!!
On the figure L the motion of the sound waves is isotropic relative to the air but it is anisotropic relative to the helicopter, because as the waves are moving away from the helicopter/source we don't have the same distance between the helicopter and the waves towards all directions!!!
Towards the direction where the distance between the helicopter/source and the wavefront is smaller we must say that the relative speed between the helicopter/source and that part of the wave is smaller, and towards the direction where the distance between the helicopter/source and the wavefront is larger, we must say that the relative speed between the helicopter and that part of the wave is larger!!!
This is anisotropic motion of the waves relative to the helicopter which is the source of the sound waves!!!
On the figure L where the source of the sound waves(helicopter) is not at the hypothetical centre of the sound waves, we must say that relative to the source(helicopter) a sound wave is not moving away at the same speed towards all directions, and the same we must say in a case where a light source is not at the hypothetical centre of the light waves that it has emit!!!
Regarding light, we know that the motion of light is not related to the motion of its source, but the same is happening with the sound!!!
The motion of light is unrelated to the motion of its source and also the motion of sound is unrelated to the motion of the source!!!
The helicopter is the source of the sound waves(Figures K & L).
We can understand when the helicopter/source is at the hypothetical centre of the sound waves(figure K), and we can understand when the helicopter/source is not at the hypothetical centre of the sound waves(figure L), and we can understand both situations regardless of whether or not the helicopter/source is on the move relative to us!!!
The same we can do with the sources of light!!!
We can understand when a light source is not at the hypothetical centre of the light waves, and we can understand this regardless of whether or not the light source is on the move relative to us, and this leads to some conclusions!!!
Next we will see various examples that will help us understand!!!
On the figure K, if someone thinks that the reason why the helicopter is at the centre of the sound waves is because it is stationary relative to the ground, he is wrong because the helicopter can be at the centre of the waves regardless of whether or not it is stationary relative to the ground, meaning that it can be at the centre of the waves while it is moving relative to the ground if there is no relative motion between the helicopter and the wind!!!
If someone sees the figure L and says that the helicopter is not at the hypothetical centre of the sound waves because it is moving relative to the ground, he is wrong because this is only one way in which this can happen.
On the figure L, we can imagine that the helicopter is on the move relative to the ground and the wind is not blowing, or we can imagine that the helicopter is stationary relative to the ground and the wind is blowing, and as the wind is blowing, the sound waves are moving with the wind!!!
On the figure L, the helicopter can be on the move relative to us on the ground or it can be stationary relative to us on the ground and the wind will be blowing, but in any case the helicopter considers its self as stationary, even in the case where it is on the move relative to the ground!!!
The same is happening with the cases where a source of light is not at the hypothetical centre of its own light waves, meaning that we could be in relative motion with a light source, but the light source will be in an inertial reference frame regarding itself as stationary while not being at the hypothetical centre of its own light waves!!!
Now, after we clarified some things, let's see what is happening.
With the help of the Michelson-Gale-Pearson experiment, the "Sagnac effect" and the ''Sagnac effect'' on the GPS systems, we can understand that the speed of light is not isotropic relative to a source which is stationary on the surface of the Earth!!!
When Albert A. Michelson saw that he could not detect anisotropy of the speed of light with the Michelson-Morley experiment, he came up with an idea for another experiment that could detect the anisotropy of the speed of light due to the Earth's rotation!!!!
That experiment was the Michelson-Gale-Pearson experiment!!!!!
Michelson came up with this idea about that new experiment because the tangential speed of the Earth's surface is too small, and the
Michelson-Morley experiment was not accurate enough in such small speeds!!!!!!
But, what the Michelson-Gale-Pearson experiment and the ''Sagnac effect'' are showing?????
The Michelson-Gale-Pearson experiment and the ''Sagnac effect'' are showing that a light source which is stationary in the surface of the Earth, will not be located at the hypothetical centre of the light wave that it will emit(see light bulb A on the figures 1-2-3)!!!!!
A light source that is stationary on the surface of the Earth, is a light source that revolves around the Earth's axis due to the Earth's rotation!!!
A light source that is stationary on the surface of the Earth (light bulb A on the figures 1-2-3), is a light source at rest in the "Earth-centered, Earth-fixed"(ECEF) frame.
A light source stationary on the surface of the Earth, is on the move relative to the "Earth-centered inertial"(ECI) frame, and it will not be at the hypothetical centre of the wave of light that it will emit(see light bulb A on the figures 1-2-3)!!!
The light bulb A and the light bulb B are in relative motion with each other(figure 1).
As we have seen on the previous example in the figure E, if two sources of light are in relative motion with each other, only the one source can be at the centre of its own light wave, meaning that we cannot have both the light bulb A and the light bulb B at the centre of their own light wave(figure 1)!!!
The light bulb A(figure 1) is not at the hypothetical centre of its own light wave because it is moving towards the East due to the rotation of the Earth!!!
As we see on the figure 1 example, the distance B is smaller than the distance A, meaning that some photons that the source has emit are closer to the source and some are farther away from the source, which means that in this case we must say that there is anisotropy of the speed of light relative to the source, which is the light bulb A!!!!
The distance A(figure 1) is the distance between the light bulb A and the photons that are emitted towards the West, and the distance B
(figure 1) is the distance between the light bulb A and the photons emitted towards the East!!!
As we see on the figure 1, we must say that the relative speed between the light bulb A and the photons that are emitted towards the East is smaller than the relative speed between the light bulb A and the photons emitted towards the West!!!!
All the photons that the light bulb A emits are making the same motion not relative to the light bulb A, but relative to something else!!!!!!
The human on the figure 1 represents a human who is stationary in the surface of the Earth.
The light bulb A(figure 1) is also stationary on the surface of the Earth.
The light bulb B(figure 1) represents a light bulb that is stationary on the "Earth-centered inertial"(ECI) frame, meaning that it does not revolve in any way around the Earth but it is on the move relative to the surface of the Earth due to the Earth's rotation.
(The light bulb B is a few metres above the ground)
The human and the light bulb A are on the move relative to the light bulb B because they revolve/rotate with the Earth, or we can say that the light bulb B is on the move relative to the human and the light bulb A!!!
The next example with the figures 2 & 3 has more analysis that will help us understand what the figure 1 shows!!!
Αll the findings are showing that a source of light that is stationary in the surface of the Earth(meaning that it revolves around the axis of the Earth because it rotates with the Earth) is not at the centre of the light wave that it will emit!!!
Also, all the findings are showing that a source of light that is very close to the surface of the Earth and it is stationary on the ECI frame, meaning that is not revolving around the Earth, will be at the centre of the light wave that it will emit, or maybe it is approximately at the centre of the light wave(it depends on how strong is the Earth's gravity)!!!
But, this is what is happening to sources very close to the surface of the Earth!!!
If a source of light is far away from the Earth, it will not be at the centre of its own light wave even if it is stationary on the ECI frame!!!
The possibility for a source of light away from a planet to be at the centre of its own light wave is extremely small!!!
But not only away from a planet, in general the possibility for a source of light to be at the centre of its own light wave is extremely small!!!
In recent years have been conducted a few Michelson-Morley type experiments using lasers, optical resonators, cryogenic oscillators, etc.
According to these new experiments there is no anisotropy to a level of 10−15, 10−16 or even 10−17 when comparing the speed of light on the two perpendicular paths where it moves.
The problem with the Michelson-Morley type experiments is that the tangential speed of the surface of the Earth is extremely small compared to the speed of light!!!
The tangential speed of the surface on the equator is 465 metres/second!!!
According to my calculations, in a latitude where the tangential speed of the surface of the Earth is 340 metres/second we will not find anisotropy on the scale of 10−13 while using interferometer experiments.
According to my calculations we must go to a level of 10−14 and lower to find anisotropy while using interferometer experiments, but down to that extremely low scales the probability of an error is extremely high.
Down to that extremely low scales, the smallest error on the high number of variables that we must take into account and the smallest error on the way that we conduct the experiment, leads to results in calculations that do not respond to reality!!!!!
This means that we cannot rely on the results of these experiments!!!
These experiments involve sources of light that are stationary on the surface of the Earth, meaning that they are stationary on the ECEF frame!!!
If we accept that the findings of these experiments are correct and there is no anisotropy, this means that we must accept that a light source which is stationary on the surface of the Earth, meaning stationary on the ECEF frame, is at the hypothetical centre of the wave of light that it will emit!!!
But if we accept that, then we must accept that a source of light which is stationary on the ECI frame, and it is on the move on the ECEF frame, will not be at the hypothetical centre of the wave of light that it will emit, meaning that if we say that the light bulb A on the examples in the figures 1-2-3 is at the hypothetical centre of the light waves, then we must say that that light bulb B on these figures will not be at the centre of the light waves, meaning that we will say that a light source which is in an inertial reference frame(light bulb B) is not at the hypothetical centre of the light wave!!!
The next example(figures 2- 3) will help us understand.
(When i'm referring to the figure 3, i'm referring to figures 3,A & 3,B)
Suppose that the light bulb A is stationary at the surface of the Earth on the Equator(figure 2), meaning that it is stationary on the "Earth-centered, Earth-fixed"(ECEF) frame.
The light bulb A rotates/revolves around the axis of the Earth, because it rotates with the Earth, meaning that it is on the move relative to the "Earth-centered-inertial"(ECI) frame.
We can use the terms "rotate" & "revolve" in order to describe the motion of the light bulb A(figure 2) around the axis of the Earth, but we can also use the term "orbit"!!!
The light bulb A is stationary relative to the surface of the Earth, but it orbits around the axis of the Earth as it rotates with the Earth!!!!
Suppose there is another light bulb on the Equator, the light bulb B(figure 2), but that light bulb stands a few centimetres above the ground and is not revolving around the axis of the Earth, meaning that it is stationary on the "Earth-centered-inertial"(ECI) frame.
The light bulb B is a few centimetres above the ground in order to be close to the light bulb A.
( A light bulb that is a few centimetres above the ground and it is stationary on the ECI frame will collide with the ground as the Earth rotates because the Earth is not a perfect sphere and has mountains, so, to help you visualise the whole situation is better to consider the Earth as a perfect and smooth sphere with no mountains.
The purpose of this example is to make a point and to help you understand, so, just imagine that the Earth is a perfect sphere. )
So, the light bulb A rotates/revolves with the Earth around the axis of rotation, but the light bulb B does not rotate/revolve around the axis of the Earth(figure 2).
While the Earth rotates, the light bulb A passes next to the light bulb B(figure 3, A).
( The figure 3(3,A & 3,B) depict how the situation will look like if we are above the light bulbs and we are looking down towards the surface of the Earth.)
Figure 2. The light bulb A is stationary at the surface of the Earth on the equator, meaning that it revolves/rotates with the Earth.
The light bulb A is stationary on the ECEF frame and is moving towards the East as the Earth rotates.
The light bulb B is also on the equator but stands a few centimetres above the ground and does not revolve around the Earth's axis,
meaning that it is stationary on the "Earth-centered inertial"(ECI) frame.
While the Earth rotates, the light bulb A passes next to the light bulb B, like we see on the figure 3, A.
The figures 3,A & 3,B depict how the situation will look like if we are above the light bulbs and we are looking down towards the surface of the Earth.
the source(figure 3, B).
Not only the motion of the light will not depend on the motion of the light bulbs/sources, but moreover, the photons which are emitted by the two light bulbs/sources will make identical motion!!!!!!!!
So, we can say that there will be created two light waves which will be stationary relative to each other!!!!
And here is the important part:
We cannot have both the light bulb A and the light bulb B at the hypothetical centre of their own light wave(figure 3,B)!!!
Only the one of the two light bulbs/sources can be at the centre of its own light wave, and the other possible reality is that both light bulbs/sources will not be at the centre of their light wave, but we cannot have both light bulbs/sources at the centre of their light wave!!!!!!!
Why???
Because the two light waves will expand with exactly the same way(figure 3, B), but the two light bulbs/sources are on the move relative to each other!!!!
And as we can understand from the "Sagnac effect" and the Michelson-Gale-Pearson experiment, a light source which is stationary in the surface of the Earth on the Equator and is revolving around the axis of the Earth is not at the hypothetical centre of its own light wave, and a light source which is not revolving around the Earth's axis is at the hypothetical centre of its own light wave, meaning that the light bulb B will be at the centre of the light wave, and the light bulb A will not be at the centre of the light wave(figure 3,B).
Due to the rotation of the Earth the light bulb A is moving towards the East, and the result is that it will not be at the hypothetical centre of its own light wave(figure 3,B)!!!
(The figures 3,A & 3,B depict how the situation will look like if we are above the two light bulbs and we are looking down towards the surface of the Earth.
The two light bulbs are passing the one next to the other in our line of sight.
If the two light bulbs are the one in front of the other in our line of sight at the moment they will emit light, the situation will look like the figure G.)
Conclusions.
We can say that there is isotropy of the speed of light relative to a source only when the source is at the hypothetical centre of the light wave!!!!!!
The light bulb B(figure 3, B) is at the hypothetical centre of its own light wave which means that there is isotropy of the speed of light relative to this source!!!
The fact that the light bulb A(figure 3, B) is not at the hypothetical centre of its own light wave, means that there is anisotropy of the speed of light relative to this specific light source!!!!!!
But, this anisotropy is not the result of a different motion of the light that it is emitted from the light bulb A!!!!!!!
On the contrary, the light emitted from the light bulb A is making the exact same motion with the light emitted from the light bulb B, and that's why the two waves of light which are produced by the two light bulbs are expanding with exactly the
same way(figure 3, B)!!!!!
But, in order to say which is the relative speed between the photons and the light bulbs, we must focus on what the photons are doing in relation to the light bulbs, and not on what the photons are doing relative to each other!!!
All the photons that the light bulb A emits are making the same motion but not relative to the light bulb A, but relative to something else!!!!!!!!!
The light bulb A has emit photons towards all directions, but as we see on the figure 3,B , the photons that are emitted towards the East are closer to the light bulb A than the photons emitted towards the West, which means that we must say that the relative speed between the light bulb A and the photons moving towards the East is smaller than the relative speed between the light bulb A and the photons moving towards the West!!!!
Important note:
If we say that the time on the light source is slower or faster it makes no difference, because the fact that remains is that as the photons that the source has emit are moving away from the source they are not all at the same distance from the source!!!
The figures 2 & 3(3,A - 3,B) are helping us to understand what the figure 1 shows.
If we say that there is anisotropy of the speed of light relative to its source, that statement does not contradict to the fact that the motion of light does not depend on the motion of the source!!!!!!!!!
The photons emitted by the two light bulbs are making the same motion(figure 3,B), but what we will regard as relative speed between the light bulbs and the photons is a different thing!!!!
On the example in the figures 2 & 3,B the light bulb A is making revolutionary motion around the axis of the Earth!!!
If the light bulb A was making linear motion the result would have been the same!!!
Imagine a scenario where the two light bulbs are in relative motion with each other at constant relative speed but the light bulb A is not making revolutionary motion!!!
Imagine that the light bulb A is making linear motion and is coming from far away from the Earth, it will pass next to the light bulb B and will move away from the Earth.
In this scenario we would have two light bulbs in relative motion with each other and both of them being in an inertial reference frame, but the result would be the same, the light bulb A will again not be at the centre of its own light wave, meaning that it will happen again what we see in the figure 3, B!!!
What about the "Sagnac effect", one may ask???
Suppose that the light from the two light waves of our example(figures 2 - 3,B) travels around the planet.
The light emitted towards the West will return to the light bulbs/sources from the East, after it travels around the planet, and the light emitted towards the East will return to the light bulbs/sources from the West, after it travels around the planet!!!!
The two light waves will move in the same way traveling around the planet!!!
The photons that are emitted towards the West will return from the East to the light bulb B simultaneously with the photons that are emitted towards the East and will return to the light bulb from the West.
This means that we have photons which are emitted by the light bulb B, and these are photons that all are emitted simultaneously by the light bulb B, and they will return back to it simultaneously after they travel around the planet, meaning that we must say that these photons were having the same speed relative to the light bulb B!!!
I'm saying that the photons are emitted simultaneously by the source because they are part of the same light wave!!!
But, the photons which are emitted by the light bulb A, and these are photons that all are emitted simultaneously by the light bulb A, will not return simultaneously to the light bulb A after they travel around the planet, and this means that we must say that these photons are not having the same speed relative to the light bulb A!!!!
This will happen because the light bulb A does not remain at the centre of the light wave(figure 3, B) because it is moving towards the East due to the rotation of the Earth!!!
The photons that are emitted towards the West, will return from the East to the light bulb A before the photons that are emitted towards the East and will return to the light bulb A from the West, and these are photons which all are emitted simultaneously by the light bulb A because they are part of the same wave!!!
The fact that the photons will not return simultaneously to the light bulb A, even though they all are emitted simultaneously by the light bulb A(the same with the light bulb B), and even though they will travel on the same path, means that we must say that the photons are not having the same speed relative to the light bulb A!!!
The people who believe that the theory of relativity is correct will argue that the motion of all the photons is the same and the different result for the two light bulbs is due to their different motion!!!
I agree with that!!!!!!
It is a combination of the motions of the light bulbs and the photons, but this is what we are focusing on!!!
The photons emitted by the two light bulbs/sources will make identical motion, but due to the different motion of the light bulbs we have different results for the two light bulbs!!!
Due to the different motion of the light bulbs/sources, the result is that the one light bulb remains at the centre of its own light wave but the other light bulb does not remain at the centre of its own light wave(figure 3,B)!!!!!
This is anisotropy, and the result of the anisotropy is the "Sagnac effect"!!!!!
The light that is emitted towards the West will return to the light bulb B simultaneously with the light emitted towards the East, after they travel around the Earth, because the light bulb B is at the centre of the light wave!!!
But, the light that is emitted towards the West will not return to the light bulb A simultaneously with the light emitted towards the
East, after they travel around the Earth, because the light bulb A is moving towards the East due to the rotation of the Earth and it is not at the centre of the light wave, as the figure 3,B shows!
All the photons that the light bulb A emits are making the same motion not relative to the light bulb A, but relative to something else!!!!!
This is happening because the motion of the photons in the vicinity of the Earth is affected & determined by the gravity of the Earth!!!!!
The motion of the photons that are emitted by the light bulbs A & B will be the same(figures 2, 3), but their motion is also affected by the gravity of the Earth, and that's why the light waves created by the two light bulbs are expanding in the same way.
So, the photons that the two light bulbs/sources emit are making the same motion inside the gravitational field of the Earth!!!
The light bulb A is on the move inside the gravitational field due to the rotation of the Earth, and it will not be at the hypothetical centre of its own light wave!!!
The light bulb B is stationary inside the gravitational field of the Earth because it does not revolve around the Earth's axis, and it will be at the hypothetical centre of the light wave!!!
On the figures 3,A & 3,B we have seen how the situation will look like if the two light bulbs/sources emitting the light as a wave towards all directions.
Next, we will see a little different scenario that maybe will be helpful to some people.
So next, on the figures 3,C & 3,D , we will see again the same case that we see in the figures 3,A & 3,B , but now we will see how the situation will look like if the the two light bulbs/sources emit a few photons, and specifically we will see a situation where the two light bulbs/sources will emit four photons, one towards the East, one towards the West, one towards the North and one toward the South.
So, what happens is that at the moment that the light bulb A is next to the light bulb B(figure 3, C), each light bulb will emit one photon with a direction towards the East, one photon with a direction towards the West, one photon with a direction towards the North, and one photon with a direction towards the South.
Therefore, there will be two photons moving towards each direction(figure 3, D), one emitted by each light bulb, and these two photons will practically be stationary relative to each other, because they will move in exactly the same way!!!
(The figures 3,C & 3,D depict how the situation will look like if we are above the two light bulbs and we are looking down towards the surface of the Earth. The two light bulbs are passing the one next to the other in our line of sight.)
Two significant observations on the figure 3, D:
First: the photons that are emitted towards the East are closer to the light bulb A than the photons that are emitted towards the West!!!
Second: the light bulb B is in-line with the photons moving towards the North and the South, but the light bulb A is not
in-line with these photons!!!
On this example that I present here the light bulb A is revolving around the axis of the Earth.
If instead of this the light bulb A is making a linear motion and is coming from a location away from the Earth, passes close to the surface and then is moving away from the Earth, the result will be the same!!!
It makes no difference whether we have a rotational/revolutionary motion or a linear motion!!!
As we see in the figure 3,D the photons emitted towards the East are closer to the light bulb A than the photons that are emitted towards the West, and the result of that is the "Sagnac effect", meaning that due to the fact that the photons emitted towards the West are further away from the light bulb A, they will reach the light bulb A before the photons that are emitted towards the East, after all the photons revolve around the planet!!!
The fact that the photons that are emitted towards the East are closer to the light bulb A than the photons emitted towards the West means that the we must say that the relative speed between the photons emitted towards the West and the light bulb A
is larger that the relative speed between the photons emitted towards the East and the light bulb A!!!
As we see on the figure 3,D , the photons emitted towards the East and the photons emitted towards the West are having the same distance from the light bulb B, meaning that there is isotropy of the speed of light for this light bulb.
Next we will see more examples that will help us understand.
Figure 6. When the light bulb B passes next to the light bulb A, each light bulb will emit light towards all directions.
The light bulb A(figure 7) is at the centre of the light wave because it is at rest inside the gravitational field of the Earth, like a light bulb which is not rotating/revolving around the Earth's axis is also at rest inside the gravitational field( see example figures 2-3)!!!!
By being stationary at the point where the axis of rotation meets the surface, the light bulb A remains stationary inside the gravitational field of the Earth!!
The light bulb B(figure 7) is not at the centre of its own light wave because it is on the move inside the gravitational field of the Earth, like a light bulb which is stationary on the equator is on the move inside the gravitational field of the Earth due to the Earth's rotation(see example figures 2-3)!!!!
The figures 7,(a) & 7,(b) are helping us to understand because we see only parts of the light waves that we see in the figure 7, and we focus on the distance between the light bulbs and the photons.
On the figure 7,(b) we see that the distance C is larger than the distance D, and this means that we must say
that the relative speed between the light bulb B and the photons that are emitted towards the one direction is larger than the relative speed between the light bulb B and the photons that are emitted towards the other direction!!!
But, that different relative speed is not the result of a different motion of the photons, on the contrary, all the photons that are emitted by the light bulbs A & B are making the same motion, but they are making the same motion inside the gravitational field they are in, which in this case is the gravitational field of the Earth!!!!!
If we say that the time on the light bulb B is slower, it makes no difference to the fact that as the photons that are emitted by the light bulb B are moving away from the source, they are not all the photons at the same distance from the light bulb B!!!
Any source of light which is stationary on the surface of the Earth and away from the point where the Earth's axis of rotation meet the surface, it is not at the centre of the light wave that it has emit, because it is on the move inside the gravitational field of the Earth due to the Earth's rotation!!!
Let's see the example.
We have the light source(light bulb) that we talk about earlier and we also have two reflectors(mirrors) in our possession, the reflectors 1 & 2.
We place the source exactly between the two reflectors, which means that the two reflectors are at the same distance from the source(figure N,1).
Light source and reflectors are stationary relative to each other.
At some point we switch-on the light source and it starts to emit light, but because we have put covers in specific places around the light source the light is moving towards the two opposite directions where the reflectors are placed.
The figure N,1 depicts this moment, meaning that it depicts the moment of the emission of light by the source(light bulb), and we see the two light waves just starting to move away from the source.
As I have said earlier, the light wave that is moving towards the one direction is at twice the distance away from the source compared to the distance between the source and the light wave moving towards the opposite direction!!!
Specifically, the light wave that is moving with a direction towards the reflector 1 is the one that is at twice the distance away from the source compared to the distance between the source and the light wave moving towards the reflector 2(figure N, 2).
Since the reflectors are stationary relative to the light source, the motion of the light waves relative to the source is also a motion relative to the reflectors!!!
So, it is very important to realise that we have a situation where relative to the source and the reflectors, the light wave moving with a direction from the reflector 2 to the reflector 1 is making twice the distance that the light wave moving with a direction from the reflector 1 to the reflector 2 is making(figure N, 2)!!!
This is very important to realise and we will need it again!!!
(This is the motion of the light relative to the specific source and reflectors, and only relative to them or any other object stationary relative to them.)
A very important note:
If the light wave that is moving towards the reflector 2 reflect somewhere and start to move towards the opposite direction meaning towards the reflector 1, it will make similar motion with the other light wave because they will be moving towards the same direction!!!
It's the direction of motion of the light that determines towards which direction the motion will be larger!!!
(I'm talking about the motion of the light waves relative to the source and the reflectors.)
If both light waves reflect somewhere and their directions of motion are reversed the thing that will also be reversed is which light wave will make larger motion relative to the source and the reflectors, because the fact that determines which light wave makes the larger motion is the direction of motion of the wave, and the light wave moving with a direction from the reflector 2 towards the reflector 1 will make twice the distance that the light wave moving with a direction from the reflector 1 to the
The fact that the light always make the same motion regardless of the motion of the source, is actually the reason why there
is anisotropy of the motion of light relative to its source!!!!
But, in order for the anisotropy to be revealed, we must use an example with the sources emitting light towards all directions, meaning emitting a circular or spherical light wave!!!!!!
On the example in the figure C it's not so easy to see the anisotropy of the speed of light.
The anisotropy of the speed of light is revealed when the sources emit light towards all directions, so in the next examples we will find why what we see in the figure C leads to the acceptance that there is anisotropy of the speed of light!!!!!!!!!
Next, an extremely important realisation.
Suppose that somewhere(anywhere, it doesn't matter where) there are two sources of light(point sources) that are moving towards each other.
These are the red light source and the green light source(figure D,a).
The sources are in relative motion with each other at constant relative speed and both sources are in an inertial reference frame.
The sources currently do not emit light.
At some point the red light source and the green light source are next to each other(figure D).
When the two sources of light are next to each other(figure D), each source will emit light towards all directions.
After the emission of the light the sources are moving away from each other because their relative motion continues.
Figure D,a. Two light sources are moving towards each other.
Figure D. When the two light sources are next to each other they will emit light towards all directions.
Two waves of light will be created, one from the light emitted by the red light source and the other from the light emitted by the green light source(figures E & F).
( The waves will be "three-dimensional waves" or in other words "spherical waves" because they will from an expanding sphere since the sources emit light towards all directions, but of course in the figures E & F we see "two-dimensional waves" or in other words "circular waves".
Instead of ''waves of light'' we can call them ''expanding bubbles of light'' or ''expanding bubbles/groups of photons'' since the sources have emit photons towards all directions)
The two light waves will expand with exactly the same way(figures E & F)!!!!
Not only the motion of the photons emitted by the two sources will not depend on the motion of the light sources, but moreover, the photons which are emitted by the two light sources will make identical motion, and that's why the two light waves will expand in exactly the same way(figures E & F)!!!!!!!
In other words we can say that there will be created two light waves which will be stationary relative to each other!!!
So, there are two light waves which expand in exactly the same way, and also there are two light sources which are in relative motion with each other, and here is the important realisation:
There are two possibilities:
First possibility(figure E): Only the one of the two sources will be at the hypothetical centre of its own light wave.
Second possibility(figure F): Both light sources will not be at the hypothetical centre of their own light wave.
The possibility of having both light sources to be located at the centre of their own light wave does not exist!!!
We cannot have both the red light source and the green light source at the centre of their light wave!!!
It doesn't matter where this example/experiment is taken place in the Universe, and it doesn't matter if one or both sources are making linear motion or if they revolve around something!!!
Only the one of the two light sources can be at the hypothetical centre of its own light wave!!!
The other possible reality is that both light sources will not be at the centre of their own light wave, but there cannot be both light sources at the centre of their own light wave!!!!!!!
Why???
Because the photons that the two sources have emit will move exactly the same and the two light waves will expand with exactly the same way(figures E & F), but the two light sources will move away from each other because they are in relative motion with each other!!!!
The two sources were next to each other when they emitted the light(figure D), but they will move away from each other because their relative motion continues!!!
Figure E. Presents the case where the one source is not at the centre of its own light wave,
meaning that there is anisotropy of the motion of light for the one source.
The green light source is not at the hypothetical centre of its own light wave.
The green light source is not at the hypothetical centre of its own light wave.
There cannot be both sources at the centre of their own light wave, which means that at least for the one source there is anisotropy of the speed of light.
Figure F. Presents the case where both sources are not at the centre of their own light wave,
meaning that there is anisotropy of the motion of light for both sources.
Both the green and the red light source are not at the hypothetical centre of their own light wave.
Both the green and the red light source are not at the hypothetical centre of their own light wave.
Two waves of light will be created, and those two waves will expand exactly in the same way, regardless if their sources are in relative motion with each other.
Let's focus on the case which is depicted in the figure E, meaning in the case where the one of the two sources is at the centre of its own light wave.
The two sources are in relative motion with each other at constant relative speed and both sources are in an inertial reference frame, meaning that each source considers itself as being at rest, as stationary!!!
But even though this happens, even though both sources are in an inertial reference frame, the motion of the light waves relative to the two sources is not the same for the two sources(figure E), because the red light source is at the centre of its own light wave but the green light source is not at the centre of its own light wave!!!
Let's see things from the point of view of the two sources(figure E):
Let's see things according to the red source's reality:
The red source(figure E) considers itself as being stationary and it "says" that the green source is on the move, therefore, if the red source is at the centre of its own light wave it is something acceptable because it is stationary, and if the green source is not at the centre of its own light wave it is also something acceptable because the green source is on the move relative to the red source!!!
Now, let's see things according to the green source's reality:
Also the green source(figure E) considers itself as being stationary and it "says" that the red source is on the move, but even though the green source considers itself as being stationary it is not at the hypothetical centre of its own light wave, and the red source which suppose to be on the move it is at the hypothetical centre of its own light wave!!!
Therefore, the reality for the green source is totally different than the reality for the red source, even though both sources are in an inertial reference frame!!!
Let's focus on the case which is depicted in the figure F, meaning in the case where both sources are not at the centre of its own light wave.
The two sources have emit light towards all directions, but as the light is moving away from the sources, the distance between the sources and the light wave is not the same towards all directions, and this applies to both sources(figure F)!!!
As the photons that each source has emit are moving away from the source, some photons are closer to the source and some photons are farther away from the source, and this applies for both sources(figure F)!!!
So,we have a case where both sources consider themselves as stationary because both are in an inertial reference frame, but as we see in the figure F, for both sources the distance between the source and the wave is not the same towards all directions, meaning that for both sources there is anisotropy of the speed of light!!!!!!
The other possibility is that there will be anisotropy of the speed of light for only the one source, in the case where the other source is at the centre of its own wave(figure E)!!!
But, the possibility to have isotropy of the speed of light for both sources does not exist because the possibility to have both sources at the hypothetical centre of their own light wave does not exist!!!!
The figure E depicts the case where the one of the two light sources is at the hypothetical centre of its own wave of light.
This is the one possibility, and the other possibility is that both the red light source and the green light source will not be at the hypothetical centre of their own light wave(figure F)!!!
On the figure E we see anisotropy of the speed of light for the one light source.
In the case where both light sources are not at the centre of their own light wave(figure F), this means that there is anisotropy of the speed of light for both sources!!!
The possibility to have both sources at the centre of their own light wave, simply does not exist!!!
The photons that consist the two waves of light will make identical motion(figures E & F)!!!
There will be created two waves of light that will expand with exactly the same way(figure E & F)!!!
In other words we can say that the two light waves will be stationary relative to each other!!!
But, since the two sources of light(red & green light source) are in relative motion with each other, only one of them can be at the hypothetical centre of the light wave that it will emit(figure E)!!!!
This means that for the source that is not at the hypothetical centre of its own light wave we must say that there is anisotropy of the speed of light relative to this source, which is the green light source on the example in the figure E!!!
Isotropy of the speed of light relative to its source exist only for the source which is at the hypothetical centre of its own wave of light, which is the red light source on the example in the figure E!!!!!!
In order to say that the motion of light that a source has emit is isotropic relative to its source, the light that this source has emit must move in the same way relative to its source towards all directions, meaning that all the parts of the light wave must be at the same distance from the source!!!
This means that when we don't have the same distance between the source and the light wave towards all directions, meaning that some parts of the light wave that the source has emit are closer to the source and other parts of the light wave are farther away from the source, this is anisotropic motion of the light relative to this specific source, which is a source that is not at the hypothetical centre of the light wave that it has emit!!!
We can say that there is isotropy of the speed of light relative to a source only when the source is at the hypothetical centre of its own light wave!!!!!!
When a source is not at the centre of its own light wave, this means that there is anisotropy of the speed of light relative to this specific source!!!!!!
But, this anisotropy is not the result of a different motion of the light!!!!!!!
The light emitted by the two sources is making the exact same motion, and that's why the two waves of light which are produced by the two light sources are expanding with exactly the same way(figure E & F)!!!!!
But, in order to say which is the relative speed between the photons and the light sources we must focus on what the photons are doing in relation to the light sources, and not on if the photons emitted by the two sources are making the same motion!!!
If we say that there is anisotropy of the motion of light relative to its source, that statement does not contradict to the fact that the motion of light does not depend on the motion of the source!!!
The motion of light may not depend on the motion of the source, but we must say that there is anisotropy of the motion of light relative to its source when the distance between the source and the light wave that this source has emit is not the same towards all directions!!!
If we say that the time on the two sources(figure F) is running slower will not make any difference, because the fact that we care about is the fact that the source does not have the same distance from all the parts of the wave that it has emit!!!
This means that as the light is moving away from the source, some parts of the wave are closer to the source and some parts of the wave are farther away from the source, and whether or not the time on the source is running slower or faster does not changes that fact!!!
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On the figure E we see a depiction with two light waves because it depicts a case where the two sources were next to each other in our line of sight when they emitted the light, meaning they were as we see in the figure D.But, in a case where the one source is in front of the other in our line of sight at the moment they are emitting light, in order
to depict the light waves we will use only one wave, because the two light waves will move in exactly the same way!!!
The figure G depicts a situation like this!!!
This example will help you understand that the possibility to have both sources at the centre of the light wave does not exist!!!
So, as we see in the figure G,(a), two sources of light are moving towards each other.
It seems that they will collide, but actually the green light source will pass behind the red light source in our line of sight.
When the green light source is behind the red light source{ figure G,(b) } both sources will emit light towards all directions.
In the figure G,(b) we don't see the green source because it is behind the red source.
After the emission of the light the relative motion of the sources continues and the sources are moving away from each other.
Two waves of light will be created(figure G), one from each light source, but in order to depict the light waves we will use only one wave(figure G) because the two light waves will expand exactly the same!!!
On the figure G we see the one light source at the centre of the light wave because it depicts a similar situation with
the figure E.
This is the one possibility, and the other possibility is that both light sources will not be at the centre of the light wave, which is what will happen in most cases.
The possibility to have both sources at the centre of the light wave does not exist!!!
(Undoubtedly, two different waves of light will be created, one by each light source, but we will use one wave for the depiction because it is a depiction in two dimensions and at the moment of the emission of the light the two sources were the one in front of the other in our line of sight.
In three dimensions we must always use two waves.)
{In almost all the examples I will use depictions with the sources being next to each other in our line of sight at the moment they will emit light, in order to see the motion of the sources and the waves separately.}
Figure G,(a). The two sources are moving towards each other, and the green light source will pass behind the red light source in our line of sight.
Figure G,(b). When the green light source is exactly behind the red light source in our light of sight, both sources will emit light towards all directions.
We don't see the green light source because it is behind the red light source!!!
Figure G. Two light waves will be created, but in order to depict the motion of the light waves in space we will use only one wave,
because the expansion of the two waves will be identical from our view point.
because the expansion of the two waves will be identical from our view point.
After the emission of the light the sources will move away from each other, and as a result,
the possibility to have both sources at the centre of the wave does not exist.
Therefore, the one possibility is that the one source is not at the hypothetical centre of the wave,
and in this case there is anisotropy of the speed of light for the one source, as we see in the figure G,
and the other possibility is that both sources are not at the hypothetical centre of the wave,
and in this case there is anisotropy of the speed of light for both sources.
the possibility to have both sources at the centre of the wave does not exist.
Therefore, the one possibility is that the one source is not at the hypothetical centre of the wave,
and in this case there is anisotropy of the speed of light for the one source, as we see in the figure G,
and the other possibility is that both sources are not at the hypothetical centre of the wave,
and in this case there is anisotropy of the speed of light for both sources.
Before analysing and explaining what is happening, let's see some facts about the famous Michelson-Morley experiment.
The Michelson-Morley experiment was conducted in an attempt to detect the anisotropy of the speed of light.
The light source that was used in the experiment was stationary on the surface of the Earth.
According to the findings of the experiment, there was no anisotropy of the speed of light relative to the source!!!
In my opinion the findings of the experiment have nothing to do with the reality, but let's skip that for now!!!
The question that I want you to think about is this:
If the light source on the experiment was emitting circular light waves or spherical light waves towards all directions, which will be the position of the source in relation to the waves if we accept that there was no anisotropy, and which will be the position of the source in relation to the light waves if the findings were showing that there is anisotropy of the speed of light???
Let's see what we will call isotropy & anisotropy of the motion of light relative to its source.
When we use the terms isotropy & anisotropy we refer to differences dependent on direction!!!
This means that if we talk about the motion of light relative to its source, we focus on the motion of light relative to its source towards different directions!!!
So, in order to say that the motion of the light that a source has emit is isotropic relative to the source, the light that the source has emit must move in the same way towards all directions relative to the source, and this is extremely important to understand because we talk about the motion of light relative to its source, and not relative to something else!!!
What does this mean???
Suppose that we have a light source that for a period of time does not emit light, for example a light bulb that is switched off, and at some point the source is switched on and emits a light wave towards all directions, meaning that it emits a spherical or circular light wave!!!
In order to say that the motion of the light wave is isotropic relative to its source, meaning to say that the relative speed between the source and the light wave is the same towards all directions, as the light wave is moving away from the source the distance between the source and the wavefront must be the same towards all directions, and this means that the source must be at the hypothetical centre of the wave of light that it has emit/produce(light source A on the figure H)!!!
If as the light wave is moving away from the source, the distance between the light source and the wavefront is not the same towards all directions, this means that we must say that the relative speed between the source and the light wave is not the same towards all directions, and this is anisotropy of the motion of the light wave relative to its source, and in this case the source is not at the hypothetical centre of the light wave that it has emit(light source B on the figure H)!!!
What is the situation that we see in the figure H??
We have a light wave moving away from its source towards all directions(figure H)!!!
The thing that we care about in order to say that there is anisotropy of the motion of the light wave relative to the source, is the fact that as the light wave is moving away from the source, we don't have the same distance between the source and the light wave towards all directions!!
If as the light wave is moving away from its source we don't have the same distance between the source and the wavefront towards all directions(as the light source B does in the figure H), this means that we must say that the relative speed between the light source and a part of the light wave is slower when this part of the wave is closer to the source, and the relative speed
between the light source and another part of the light wave is higher when this part of the wave is farther away from the source!!!
This is extremely important: We talk about the relative speed between the source and the wave, and we want to see if the relative speed between the source and the wave is the same towards all directions!!!
The motion of light does not depend on the motion of the source, but we are not talking about that here!!!
We talk about the relative motion between the light and the source, and specifically, since we have a wave of light expanding towards all directions, we focus on the expansion of the light wave relative to its source!!!
We don't care about the motion of light relative to something else!!!
We focus on the relative motion & speed between the source and the light!!!
If the distance between the source and the wavefront is the same towards all directions(light source A on the figure H), this means that we must say that all the parts of the wavefront towards all directions have the same speed relative to the source!!!
Regarding the light source B on the figure H, we must say that relative to the source the light wave is not moving away at the same speed towards all directions!!!
The relative speed between the light source B and the light wave is not the same towards all directions, because as the light wave is moving away from its source we don't have the same distance between the source and the wavefront towards all directions!!!
Regarding the light source A on the figure H, we must say that relative to the source the light wave is moving away at the same speed towards all directions!!!
The relative speed between the light source A and the light wave is the same towards all directions, because as the light wave is moving away from its source we have the same distance between the source and the wavefront towards all directions!!!
So, in a few words:
In order to say that there is isotropy of the motion of light relative to its source, the source must be at the hypothetical centre of the light wave that it will emit(light source A on the figure H).
There is a big error of the scientific community when they try to exlain the "doppler effect" in light, which is an error in the way that we think that the light is moving away from the source!!!
This is extremely important: We talk about the relative speed between the source and the wave, and we want to see if the relative speed between the source and the wave is the same towards all directions!!!
The motion of light does not depend on the motion of the source, but we are not talking about that here!!!
We talk about the relative motion between the light and the source, and specifically, since we have a wave of light expanding towards all directions, we focus on the expansion of the light wave relative to its source!!!
We don't care about the motion of light relative to something else!!!
We focus on the relative motion & speed between the source and the light!!!
If the distance between the source and the wavefront is the same towards all directions(light source A on the figure H), this means that we must say that all the parts of the wavefront towards all directions have the same speed relative to the source!!!
Regarding the light source B on the figure H, we must say that relative to the source the light wave is not moving away at the same speed towards all directions!!!
The relative speed between the light source B and the light wave is not the same towards all directions, because as the light wave is moving away from its source we don't have the same distance between the source and the wavefront towards all directions!!!
Regarding the light source A on the figure H, we must say that relative to the source the light wave is moving away at the same speed towards all directions!!!
The relative speed between the light source A and the light wave is the same towards all directions, because as the light wave is moving away from its source we have the same distance between the source and the wavefront towards all directions!!!
Figure H. If the source of the light wave is at the hypothetical centre of the wave, as the light source A does,
in this case we have isotropy of the speed of light relative to this specific source.
If the source of the light wave is not at the hypothetical centre of the wave, as the light source B does,
in this case we have anisotropy of the speed of light relative to this specific source.
in this case we have isotropy of the speed of light relative to this specific source.
If the source of the light wave is not at the hypothetical centre of the wave, as the light source B does,
in this case we have anisotropy of the speed of light relative to this specific source.
So, in a few words:
In order to say that there is isotropy of the motion of light relative to its source, the source must be at the hypothetical centre of the light wave that it will emit(light source A on the figure H).
If the light source is not at the hypothetical centre of the wave of light that it has emit(light source B on the figure H), this is anisotropy of the motion of light relative to its source!!!
Important note.
Both the light source A and the light source B are in an inertial reference frame(figure H), meaning that we can be in relative motion with the source but the source considers its self as stationary and us on the move!!!
Don't get me wrong, the motion of light does not depend on the motion of the source, it depends on something else, but here I'm talking about the relative motion between the light source and the light!!!
The fact that the motion of light does not depend on the motion of the source it's actually the reason why there is anisotropy of the motion of light relative to its source!!!
Important note.
Both the light source A and the light source B are in an inertial reference frame(figure H), meaning that we can be in relative motion with the source but the source considers its self as stationary and us on the move!!!
Don't get me wrong, the motion of light does not depend on the motion of the source, it depends on something else, but here I'm talking about the relative motion between the light source and the light!!!
The fact that the motion of light does not depend on the motion of the source it's actually the reason why there is anisotropy of the motion of light relative to its source!!!
We don't care about the reason why the source is not at the hypothetical centre of the light wave!!!
It can be because of the motion of the source or because of the motion of the photons or both!!!
The thing that matters is the fact that the light source is not at the hypothetical centre of the light wave that it has emit!!!
When the light source is not at the centre of the light wave this means that there are parts of the wavefront that are closer to the source and parts of the wavefront that are farther away from the source, and in this case we must say that the relative speed between the source and some parts of the wave is lower, and the relative speed between the source and some other parts of the wave is higher!!!
The reason why this is happening is irrelevant to this conclusion!!!
A significant error of the scientific community.
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An important note regarding the Michelson-Morley experiment that will help us understand the relation between the light source and the expanding light wave.The Michelson-Morley experiment was conducted in an attempt to detect the anisotropy of the speed of light.
The light source that was used in the experiment was stationary on the surface of the Earth.
According to the findings of the experiment, there was no anisotropy of the speed of light relative to the source!!!
But, what it means if we accept the findings of the experiment???
The light source on the experiment did not emitted circular or spherical light waves, but let's imagine that it did emitted circular or spherical light waves!!!
What it means about the relation between the source and the light waves that the source has emit, if we accept that there is
no anisotropy of the speed of light relative to the source???
It means that the light source that was used on the experiment, and was stationary on the surface of the Earth, was at the hypothetical centre of the light waves that it has emitted, meaning that, according to the result of the experiment, we where having the situation that we see for the light source A on the figure H!!!
But, what if the findings of the experiment where showing that there was anisotropy of the speed of light relative to the source???
If the results of the experiment where showing that there was anisotropy of the speed of light relative to the source, in this case we would have to say that the light source was not at the hypothetical centre of the light waves that it has emitted, meaning that we would be having the situation that we see for the light source B on the figure H!!!
It is very simple!!!
If we say that there is no anisotropy of the speed of light relative to a source, this means that the light source is at the hypothetical centre of the light waves that it will emit!!!
If the light source is not at the hypothetical centre of the light waves, in this case we have anisotropy of the speed of light relative to the source!!!
......................................................................................................................................................................
A significant error of the scientific community.
It is an error which has to do with the position of the light source in relation to the expanding light waves!!!
When scientists want to depict a case where a light source and an observer(human, car, spaceship, etc.) are stationary relative to each other, they always place the light source at the hypothetical centre of the light waves that it has emit(figure I,a)!!!
But this is totally wrong because whether or not an observer is stationary relative to a source is unrelated to whether or not the source is at the hypothetical centre of the light waves that it has emit!!!
We can have a case where a light source and an observer are stationary relative to each other and the source will not be at the hypothetical centre of the light waves!!!
It is wrong to always depict a source at the hypothetical centre of its own light waves when there is no relative motion between an observer and the source!!!
It is wrong to think that the source is always at the hypothetical centre of the light waves when there is no relative motion between us and the source!!!
It is totally wrong to correlate the fact that there is no relative motion between the source and the observer with the probability of the source being at the centre of its own light waves!!!
If a case where an observer and a light source are stationary relative to each other, the observer will receive the light waves(that the source will emit) at the same rate at which they are emitted by the source, regardless of whether or not the source is at the hypothetical centre of the light waves!!!
At the end of this paper, on the example with the figures 12, 13, 14 & 15, I explain what is happening!!!
Also, the scientists, when they want to depict a case where the observer is on the move but the source is not, they always place the light source at the hypothetical centre of the light waves that it has emit(figure I,b)!!!
They are depicting the light source not at the hypothetical centre of the waves only when they are depicting the source to be on the move and the observer is not(figure I,c)!!!
If for example we have a light source and a human in relative motion with each other, when they depict the human on the move they have the source at the hypothetical centre of the light waves, but when they depict the source on the move they have the source not at the centre of the light waves!!!
But this is totally wrong!!!
Whether or not the light source is at the hypothetical centre of the light waves that it has emit, is unrelated to whether or not there is relative motion between an observer and the source!!!
Whether or not the light source is at the hypothetical centre of its own light waves, is something that must be evaluated independently from anything else!!!
At the end of this paper, on the example with the figures 12, 13, 14 & 15, you will see that we can have a light source not to be at the hypothetical centre of the light waves that it will emit, and an observer stationary relative to the source will not detect any difference on the rate/frequency in which he will receive the waves!!!
But this is totally wrong because whether or not an observer is stationary relative to a source is unrelated to whether or not the source is at the hypothetical centre of the light waves that it has emit!!!
We can have a case where a light source and an observer are stationary relative to each other and the source will not be at the hypothetical centre of the light waves!!!
It is wrong to always depict a source at the hypothetical centre of its own light waves when there is no relative motion between an observer and the source!!!
It is wrong to think that the source is always at the hypothetical centre of the light waves when there is no relative motion between us and the source!!!
It is totally wrong to correlate the fact that there is no relative motion between the source and the observer with the probability of the source being at the centre of its own light waves!!!
If a case where an observer and a light source are stationary relative to each other, the observer will receive the light waves(that the source will emit) at the same rate at which they are emitted by the source, regardless of whether or not the source is at the hypothetical centre of the light waves!!!
At the end of this paper, on the example with the figures 12, 13, 14 & 15, I explain what is happening!!!
Also, the scientists, when they want to depict a case where the observer is on the move but the source is not, they always place the light source at the hypothetical centre of the light waves that it has emit(figure I,b)!!!
They are depicting the light source not at the hypothetical centre of the waves only when they are depicting the source to be on the move and the observer is not(figure I,c)!!!
If for example we have a light source and a human in relative motion with each other, when they depict the human on the move they have the source at the hypothetical centre of the light waves, but when they depict the source on the move they have the source not at the centre of the light waves!!!
But this is totally wrong!!!
Whether or not the light source is at the hypothetical centre of the light waves that it has emit, is unrelated to whether or not there is relative motion between an observer and the source!!!
Whether or not the light source is at the hypothetical centre of its own light waves, is something that must be evaluated independently from anything else!!!
At the end of this paper, on the example with the figures 12, 13, 14 & 15, you will see that we can have a light source not to be at the hypothetical centre of the light waves that it will emit, and an observer stationary relative to the source will not detect any difference on the rate/frequency in which he will receive the waves!!!
......................................................................................................
At the end of this paper, there are some clarifications regarding the "doppler effect" in light and the position of the source in relation to the light waves, and also there are explanations about the "redshift" and the "blueshift" meaning the changes in the energy of the photons......................................................................................................
Let's see the significant errors of the scientific community regarding the doppler effect in light, which have to do with the position of the light source in relation to the light waves!!!
When scientists want to explain the "doppler effect" in light, they use pictures which are similar with the following three figures(figures I,a - I,b - I,c).
In the next three figures we have a source of light and an observer which are either stationary or on the move relative to each other, and the light source is emitting light waves.
Figure I,a.
When scientists want to depict a case where we have a source of light and an observer which are stationary relative to each other, they always place the light source at the hypothetical centre of the light waves, as we see in the figure I,a!!!
So, the scientific community believes that when there is no relative motion between the light source and an observer, the light source is always at the hypothetical centre of the light waves that it has emit!!!
The is totally wrong, because actually the light source is not at the hypothetical centre of the light waves!!!
Whether or not the light source is at the hypothetical centre of the light waves that it has emit, does not correlate in any way to the fact that there is no relative motion between the light source and the observer, meaning that the depiction that we see in the figure I,a is wrong!!
Whether or not the light source is at the hypothetical centre of the light waves that it has emit, is something that must be evaluated independently from anything else!!!
To think that when there is no relative motion between the light source and us, the light source is always at the hypothetical centre of its own light waves, it is totally wrong!!!
In fact, most of the time the light sources are not at the hypothetical centre of their own light waves!!!
What the figure I,a shows is wrong.
In this picture the light source and the human are stationary relative to each other.
To think that when there is no relative motion between the light source and an observer,
the source is always at the hypothetical centre of its own light waves, it is totally wrong!!!
Whether or not the light source is at the hypothetical centre of the light waves that it has emit,
is totally unrelated to the fact that there is no relative motion between the light source and the observer.
When scientists want to explain the "doppler effect" in light and want to depict cases where we have a light source and an observer in relative motion with each other, they use pictures which are similar with the figures I,b & I,c.
Figure I,b.
In the figure I,b we see the depiction of a case where there is relative motion between the light source and the observer, but the light source is depicted as stationary and the observer is depicted on the move.
In a case like this, the scientific community always place the light source at the hypothetical centre of the light waves!!!
This is totally wrong, and it is totally wrong for the same reasons that I mention for the figure I,a!!!
Whether or not the light source is regarded as stationary(figure I,b) and whether or not there is relative motion between the light source and the observer, is unrelated to the probability for the source to be at the hypothetical centre of the light waves that it has emit, meaning that the depiction that we see in the figure I,b where the light source is at the hypothetical centre of the light waves, is wrong!!!
Whether or not the light source is at the hypothetical centre of the light waves that it has emit, is something that must be evaluated independently from anything else!!!
We can understand when a light source is not at the hypothetical centre of the light waves, and we can understand this regardless of whether or not there is relative motion between the light source and us, and regardless of whether or not the light source is regarded as stationary!!!
What the figure I,b shows is wrong.
Whether or not the source is considered to be stationary(figure I,b)
is unrelated to the probability for the source to be at the hypothetical centre of the light waves that it has emit!!!
Figure I,c.
In the figure I,c we see again the depiction of a case where we have relative motion between the light source and the observer, but now the observer is depicted as stationary and the light source is depicted to be on the move.
In this case, the scientists depict the source not at the hypothetical centre of the light waves!!!
This is the only case where the scientific community depicts the light source not to be at the hypothetical centre of its own light waves!!!
So, the figures I,b & I,c both depict cases where we have relative motion between the light source and the observer, but on the one case we have the source at the centre of the light waves, and on the other case we have the source not at the centre of the light waves!!!
Both depictions are wrong(the figures I,b & I,c), because whether or not the light source is considered to be on the move relative to an observer is unrelated to the probability for the light source to be at the hypothetical centre of the light waves!!!
Whether or not the light source is at the hypothetical centre of the light waves that it has emit, is something that must be evaluated independently from anything else!!!
We can have a light source which will regard as on the move relative to us, and the light source could be at the hypothetical centre of the light waves that it has emit!!!
Let's see an example using sound waves and the doppler effect in order to help us understand what I mean when I talk about the anisotropy of the motion of the wave relative to its source!!!
Suppose that we have a helicopter up in the air in two different scenarios.
In the first scenario that we see in the figure K, there is no relative motion between the helicopter and the air.
In the second scenario that we see in the figure L, there is relative motion between the helicopter and the air.
In both scenarios the engine of the helicopter is working and produces sound waves.
So, on the figure K we have the helicopter up in the air and its engine is running and it produces sound waves.
In the example that we see in the figure K, there is no relative motion between the helicopter and the air.
We can imagine that the helicopter is stationary relative to the ground and the wind is not blowing, or we can imagine that the wind is blowing and the helicopter is moving towards the same direction and with the same speed as the air does, but the important fact is that there is no relative motion between the helicopter and the air.
The helicopter, which is the source of the sound waves, will be at the hypothetical centre of the sound waves(figure K).
On the example that we see in the figure K, as the sound waves expanding and moving away from the helicopter(source), we have the same distance between the source/helicopter and the waves towards all directions, and this means that we will say that towards all directions the waves are moving away from the helicopter/source at the same rate/speed!!!
In the figure K, the relative speed between the helicopter/source and the sound waves is the same towards all directions!!!
In the figure K the motion of the sound waves is isotropic relative to the air, and it is also isotropic relative to the helicopter!!!
On the figure L the helicopter is up in the air, but in this scenario there is relative motion between the air and the helicopter.
There are various ways that we can imagine in order to have relative motion between the helicopter and the air.
We can imagine that the helicopter is on the move relative to the ground, or we can imagine that the helicopter is stationary relative to the ground but the wind is blowing, or we can imagine that both the helicopter and the air are on the move relative to the ground and that also the air and the helicopter are in relative motion with each other!!!
The helicopter, which is the source of the sound waves, will not be at the hypothetical centre of the sound waves(figure L).
On the example in the figure L, as the sound waves expanding and moving away from the helicopter(source), they don't move away from the helicopter at the same rate/speed towards all directions!!!
Towards the direction where the distance between the helicopter(source) and the sound waves is smaller we must say that the relative speed between the helicopter(source) and the wave is smaller, and towards the direction where the distance between the helicopter and the wave is larger we must say that the relative speed between the helicopter(source) and the wave is larger!!!
In the figure L, the relative speed between the helicopter/source and the sound waves is not the same towards all directions!!!
In the figure L the motion of the sound waves is isotropic relative to the air, but it is anisotropic relative to the helicopter!!!
As you can see on the figures K & L, I did not put an arrow on the helicopter to show that the helicopter is on the move because we don't care about whether or not the helicopter is on the move relative to the ground!!!
The thing that we care about is the whether or not there is relative motion between the air and the helicopter!!!
Figure K. In this scenario there is no relative motion between the air and the helicopter.
Comparing the examples in the figures K & L, in both examples the motion of the sound waves is isotropic relative to the air, but the motion of the sound waves relative to the helicopter(source) is not the same on the two figures!!!
In the figure K the motion of the sound waves relative to the helicopter(source) is isotropic, but on the figure L the motion of the sound waves relative to the helicopter/source is anisotropic!!!
On the figure L the motion of the sound waves is isotropic relative to the air but it is anisotropic relative to the helicopter, because as the waves are moving away from the helicopter/source we don't have the same distance between the helicopter and the waves towards all directions!!!
Towards the direction where the distance between the helicopter/source and the wavefront is smaller we must say that the relative speed between the helicopter/source and that part of the wave is smaller, and towards the direction where the distance between the helicopter/source and the wavefront is larger, we must say that the relative speed between the helicopter and that part of the wave is larger!!!
This is anisotropic motion of the waves relative to the helicopter which is the source of the sound waves!!!
On the figure L where the source of the sound waves(helicopter) is not at the hypothetical centre of the sound waves, we must say that relative to the source(helicopter) a sound wave is not moving away at the same speed towards all directions, and the same we must say in a case where a light source is not at the hypothetical centre of the light waves that it has emit!!!
Regarding light, we know that the motion of light is not related to the motion of its source, but the same is happening with the sound!!!
The motion of light is unrelated to the motion of its source and also the motion of sound is unrelated to the motion of the source!!!
The helicopter is the source of the sound waves(Figures K & L).
We can understand when the helicopter/source is at the hypothetical centre of the sound waves(figure K), and we can understand when the helicopter/source is not at the hypothetical centre of the sound waves(figure L), and we can understand both situations regardless of whether or not the helicopter/source is on the move relative to us!!!
The same we can do with the sources of light!!!
We can understand when a light source is not at the hypothetical centre of the light waves, and we can understand this regardless of whether or not the light source is on the move relative to us, and this leads to some conclusions!!!
Next we will see various examples that will help us understand!!!
On the figure K, if someone thinks that the reason why the helicopter is at the centre of the sound waves is because it is stationary relative to the ground, he is wrong because the helicopter can be at the centre of the waves regardless of whether or not it is stationary relative to the ground, meaning that it can be at the centre of the waves while it is moving relative to the ground if there is no relative motion between the helicopter and the wind!!!
If someone sees the figure L and says that the helicopter is not at the hypothetical centre of the sound waves because it is moving relative to the ground, he is wrong because this is only one way in which this can happen.
On the figure L, we can imagine that the helicopter is on the move relative to the ground and the wind is not blowing, or we can imagine that the helicopter is stationary relative to the ground and the wind is blowing, and as the wind is blowing, the sound waves are moving with the wind!!!
On the figure L, the helicopter can be on the move relative to us on the ground or it can be stationary relative to us on the ground and the wind will be blowing, but in any case the helicopter considers its self as stationary, even in the case where it is on the move relative to the ground!!!
The same is happening with the cases where a source of light is not at the hypothetical centre of its own light waves, meaning that we could be in relative motion with a light source, but the light source will be in an inertial reference frame regarding itself as stationary while not being at the hypothetical centre of its own light waves!!!
Now, after we clarified some things, let's see what is happening.
With the help of the Michelson-Gale-Pearson experiment, the "Sagnac effect" and the ''Sagnac effect'' on the GPS systems, we can understand that the speed of light is not isotropic relative to a source which is stationary on the surface of the Earth!!!
When Albert A. Michelson saw that he could not detect anisotropy of the speed of light with the Michelson-Morley experiment, he came up with an idea for another experiment that could detect the anisotropy of the speed of light due to the Earth's rotation!!!!
That experiment was the Michelson-Gale-Pearson experiment!!!!!
Michelson came up with this idea about that new experiment because the tangential speed of the Earth's surface is too small, and the
Michelson-Morley experiment was not accurate enough in such small speeds!!!!!!
But, what the Michelson-Gale-Pearson experiment and the ''Sagnac effect'' are showing?????
The Michelson-Gale-Pearson experiment and the ''Sagnac effect'' are showing that a light source which is stationary in the surface of the Earth, will not be located at the hypothetical centre of the light wave that it will emit(see light bulb A on the figures 1-2-3)!!!!!
A light source that is stationary on the surface of the Earth, is a light source that revolves around the Earth's axis due to the Earth's rotation!!!
A light source that is stationary on the surface of the Earth (light bulb A on the figures 1-2-3), is a light source at rest in the "Earth-centered, Earth-fixed"(ECEF) frame.
A light source stationary on the surface of the Earth, is on the move relative to the "Earth-centered inertial"(ECI) frame, and it will not be at the hypothetical centre of the wave of light that it will emit(see light bulb A on the figures 1-2-3)!!!
The fact that the light source (see light bulb A on the figures 1-2-3) is not at the centre of the light wave means that we must say that there
is anisotropy of the speed of light relative to this source!!!
Important note.
A light source that is stationary on the surface of the Earth, is at the centre of the light wave that it will emit, only if it is located at the point where the Earth's axis of rotation meet the surface!!!!
A light source located at the point where the Earth's axis of rotation meet the surface, is stationary in the "Earth-centered inertial"(ECI) frame.
Any source of light which is stationary on the surface of the Earth but it is away from the point where the axis of the rotation meet the surface, it will not be at the centre of the light wave that it will emit, because it is on the move inside the gravitational field of the Earth and it is on the move in the "Earth-centered inertial"(ECI) frame, and that happens due to the Earth's rotation.
If a light source is not revolving/rotating at all around the Earth's axis, meaning a light source stationary on the "Earth-centered inertial"(ECI) frame, that light source will be at the centre of the light wave that it will emit(see light bulb B on the figures 1-2-3) because it is stationary inside the gravitational field of the Earth!!!
But, i'm talking about a source which is very close to the surface of the Earth!!!
If the source is far away from the planet, it will not be at the centre of its own light wave if it is stationary on the "Earth-centered inertial"(ECI) frame because it is far away from the influence of the Earth's gravity!!!
On the figure 1, the human the trees and the light bulb A are stationary on the surface of the Earth meaning that they are actually revolving with the Earth around its axis, meaning that they are moving towards the East as the Earth rotates!!!
The light bulb B(figure 1) is stationary on the "Earth-centered inertial"(ECI) frame, meaning that the light bulb B is not revolving at all around the axis of the Earth!!!
The light bulb B stands a few metres above the surface of the Earth.
To a human stationary on the ground, the light bulb B(figure 1) will appear moving towards the West, like also the Sun and the Stars appear moving towards the West, because the human is moving towards the East due to the rotation of the Earth!!!
is anisotropy of the speed of light relative to this source!!!
Important note.
A light source that is stationary on the surface of the Earth, is at the centre of the light wave that it will emit, only if it is located at the point where the Earth's axis of rotation meet the surface!!!!
A light source located at the point where the Earth's axis of rotation meet the surface, is stationary in the "Earth-centered inertial"(ECI) frame.
Any source of light which is stationary on the surface of the Earth but it is away from the point where the axis of the rotation meet the surface, it will not be at the centre of the light wave that it will emit, because it is on the move inside the gravitational field of the Earth and it is on the move in the "Earth-centered inertial"(ECI) frame, and that happens due to the Earth's rotation.
If a light source is not revolving/rotating at all around the Earth's axis, meaning a light source stationary on the "Earth-centered inertial"(ECI) frame, that light source will be at the centre of the light wave that it will emit(see light bulb B on the figures 1-2-3) because it is stationary inside the gravitational field of the Earth!!!
But, i'm talking about a source which is very close to the surface of the Earth!!!
If the source is far away from the planet, it will not be at the centre of its own light wave if it is stationary on the "Earth-centered inertial"(ECI) frame because it is far away from the influence of the Earth's gravity!!!
On the figure 1, the human the trees and the light bulb A are stationary on the surface of the Earth meaning that they are actually revolving with the Earth around its axis, meaning that they are moving towards the East as the Earth rotates!!!
The light bulb B(figure 1) is stationary on the "Earth-centered inertial"(ECI) frame, meaning that the light bulb B is not revolving at all around the axis of the Earth!!!
The light bulb B stands a few metres above the surface of the Earth.
To a human stationary on the ground, the light bulb B(figure 1) will appear moving towards the West, like also the Sun and the Stars appear moving towards the West, because the human is moving towards the East due to the rotation of the Earth!!!
Figure 1. In this picture I have put an arrow on the light bulb A, on the human and on the trees, indicating that they are moving towards the East as the Earth rotates.
The light bulb B is stationary on the "Earth-centered inertial"(ECI) frame, meaning that the light bulb B does not revolve around the axis of the Earth.
The light bulb B is stationary on the "Earth-centered inertial"(ECI) frame, meaning that the light bulb B does not revolve around the axis of the Earth.
The light bulb A is stationary on the surface of the Earth, meaning that the light bulb A is stationary on the "Earth-centered, Earth-fixed"(ECEF) frame,
which means that the light bulb A revolves with the Earth around the Earth's axis.
The light bulb B is a few metres above the surface of the Earth.
which means that the light bulb A revolves with the Earth around the Earth's axis.
The light bulb B is a few metres above the surface of the Earth.
The light bulb A and the light bulb B are in relative motion with each other(figure 1).
As we have seen on the previous example in the figure E, if two sources of light are in relative motion with each other, only the one source can be at the centre of its own light wave, meaning that we cannot have both the light bulb A and the light bulb B at the centre of their own light wave(figure 1)!!!
The light bulb A(figure 1) is not at the hypothetical centre of its own light wave because it is moving towards the East due to the rotation of the Earth!!!
As we see on the figure 1 example, the distance B is smaller than the distance A, meaning that some photons that the source has emit are closer to the source and some are farther away from the source, which means that in this case we must say that there is anisotropy of the speed of light relative to the source, which is the light bulb A!!!!
The distance A(figure 1) is the distance between the light bulb A and the photons that are emitted towards the West, and the distance B
(figure 1) is the distance between the light bulb A and the photons emitted towards the East!!!
As we see on the figure 1, we must say that the relative speed between the light bulb A and the photons that are emitted towards the East is smaller than the relative speed between the light bulb A and the photons emitted towards the West!!!!
All the photons that the light bulb A emits are making the same motion not relative to the light bulb A, but relative to something else!!!!!!
The light bulb A(figure 1) is also stationary on the surface of the Earth.
The light bulb B(figure 1) represents a light bulb that is stationary on the "Earth-centered inertial"(ECI) frame, meaning that it does not revolve in any way around the Earth but it is on the move relative to the surface of the Earth due to the Earth's rotation.
(The light bulb B is a few metres above the ground)
The human and the light bulb A are on the move relative to the light bulb B because they revolve/rotate with the Earth, or we can say that the light bulb B is on the move relative to the human and the light bulb A!!!
The next example with the figures 2 & 3 has more analysis that will help us understand what the figure 1 shows!!!
Αll the findings are showing that a source of light that is stationary in the surface of the Earth(meaning that it revolves around the axis of the Earth because it rotates with the Earth) is not at the centre of the light wave that it will emit!!!
Also, all the findings are showing that a source of light that is very close to the surface of the Earth and it is stationary on the ECI frame, meaning that is not revolving around the Earth, will be at the centre of the light wave that it will emit, or maybe it is approximately at the centre of the light wave(it depends on how strong is the Earth's gravity)!!!
But, this is what is happening to sources very close to the surface of the Earth!!!
If a source of light is far away from the Earth, it will not be at the centre of its own light wave even if it is stationary on the ECI frame!!!
The possibility for a source of light away from a planet to be at the centre of its own light wave is extremely small!!!
But not only away from a planet, in general the possibility for a source of light to be at the centre of its own light wave is extremely small!!!
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Important note.In recent years have been conducted a few Michelson-Morley type experiments using lasers, optical resonators, cryogenic oscillators, etc.
According to these new experiments there is no anisotropy to a level of 10−15, 10−16 or even 10−17 when comparing the speed of light on the two perpendicular paths where it moves.
The problem with the Michelson-Morley type experiments is that the tangential speed of the surface of the Earth is extremely small compared to the speed of light!!!
The tangential speed of the surface on the equator is 465 metres/second!!!
According to my calculations, in a latitude where the tangential speed of the surface of the Earth is 340 metres/second we will not find anisotropy on the scale of 10−13 while using interferometer experiments.
According to my calculations we must go to a level of 10−14 and lower to find anisotropy while using interferometer experiments, but down to that extremely low scales the probability of an error is extremely high.
Down to that extremely low scales, the smallest error on the high number of variables that we must take into account and the smallest error on the way that we conduct the experiment, leads to results in calculations that do not respond to reality!!!!!
This means that we cannot rely on the results of these experiments!!!
These experiments involve sources of light that are stationary on the surface of the Earth, meaning that they are stationary on the ECEF frame!!!
If we accept that the findings of these experiments are correct and there is no anisotropy, this means that we must accept that a light source which is stationary on the surface of the Earth, meaning stationary on the ECEF frame, is at the hypothetical centre of the wave of light that it will emit!!!
But if we accept that, then we must accept that a source of light which is stationary on the ECI frame, and it is on the move on the ECEF frame, will not be at the hypothetical centre of the wave of light that it will emit, meaning that if we say that the light bulb A on the examples in the figures 1-2-3 is at the hypothetical centre of the light waves, then we must say that that light bulb B on these figures will not be at the centre of the light waves, meaning that we will say that a light source which is in an inertial reference frame(light bulb B) is not at the hypothetical centre of the light wave!!!
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The next example(figures 2- 3) will help us understand.
(When i'm referring to the figure 3, i'm referring to figures 3,A & 3,B)
Suppose that the light bulb A is stationary at the surface of the Earth on the Equator(figure 2), meaning that it is stationary on the "Earth-centered, Earth-fixed"(ECEF) frame.
The light bulb A rotates/revolves around the axis of the Earth, because it rotates with the Earth, meaning that it is on the move relative to the "Earth-centered-inertial"(ECI) frame.
We can use the terms "rotate" & "revolve" in order to describe the motion of the light bulb A(figure 2) around the axis of the Earth, but we can also use the term "orbit"!!!
The light bulb A is stationary relative to the surface of the Earth, but it orbits around the axis of the Earth as it rotates with the Earth!!!!
Suppose there is another light bulb on the Equator, the light bulb B(figure 2), but that light bulb stands a few centimetres above the ground and is not revolving around the axis of the Earth, meaning that it is stationary on the "Earth-centered-inertial"(ECI) frame.
The light bulb B is a few centimetres above the ground in order to be close to the light bulb A.
( A light bulb that is a few centimetres above the ground and it is stationary on the ECI frame will collide with the ground as the Earth rotates because the Earth is not a perfect sphere and has mountains, so, to help you visualise the whole situation is better to consider the Earth as a perfect and smooth sphere with no mountains.
The purpose of this example is to make a point and to help you understand, so, just imagine that the Earth is a perfect sphere. )
So, the light bulb A rotates/revolves with the Earth around the axis of rotation, but the light bulb B does not rotate/revolve around the axis of the Earth(figure 2).
While the Earth rotates, the light bulb A passes next to the light bulb B(figure 3, A).
( The figure 3(3,A & 3,B) depict how the situation will look like if we are above the light bulbs and we are looking down towards the surface of the Earth.)
The light bulb A is stationary on the ECEF frame and is moving towards the East as the Earth rotates.
The light bulb B is also on the equator but stands a few centimetres above the ground and does not revolve around the Earth's axis,
meaning that it is stationary on the "Earth-centered inertial"(ECI) frame.
While the Earth rotates, the light bulb A passes next to the light bulb B, like we see on the figure 3, A.
The light bulb A is stationary on the surface of the Earth on the equator, which means that it revolves/rotates
around the axis of the Earth due to the rotation of the Earth and is moving towars the East.
The light bulb B is also at the equator but it is a few centimetres above the ground and does not revolve/rotate around the axis of the Earth,
around the axis of the Earth due to the rotation of the Earth and is moving towars the East.
The light bulb B is also at the equator but it is a few centimetres above the ground and does not revolve/rotate around the axis of the Earth,
meaning that it is stationary on the ECI reference frame.
When the light bulb A passes next to the light bulb B(figure 3, A) both light bulbs will emit light towards all directions.
Two waves of light will be created(figure 3, B), and the light bulb A will not be at the hypothetical centre of its own light wave.
Two waves of light will be created(figure 3, B), and the light bulb A will not be at the hypothetical centre of its own light wave.
When the light bulb A passes next to the light bulb B(figure 3, A) the two light bulbs will emit light towards all directions.
Two waves of light will be created, one from the light emitted by the light bulb A and the other from the light emitted by the
light bulb B(figure 3, B).
The two light waves will expand with exactly the same way because the motion of the light is unrelated to the motion of Two waves of light will be created, one from the light emitted by the light bulb A and the other from the light emitted by the
light bulb B(figure 3, B).
the source(figure 3, B).
Not only the motion of the light will not depend on the motion of the light bulbs/sources, but moreover, the photons which are emitted by the two light bulbs/sources will make identical motion!!!!!!!!
So, we can say that there will be created two light waves which will be stationary relative to each other!!!!
And here is the important part:
We cannot have both the light bulb A and the light bulb B at the hypothetical centre of their own light wave(figure 3,B)!!!
Only the one of the two light bulbs/sources can be at the centre of its own light wave, and the other possible reality is that both light bulbs/sources will not be at the centre of their light wave, but we cannot have both light bulbs/sources at the centre of their light wave!!!!!!!
Why???
Because the two light waves will expand with exactly the same way(figure 3, B), but the two light bulbs/sources are on the move relative to each other!!!!
And as we can understand from the "Sagnac effect" and the Michelson-Gale-Pearson experiment, a light source which is stationary in the surface of the Earth on the Equator and is revolving around the axis of the Earth is not at the hypothetical centre of its own light wave, and a light source which is not revolving around the Earth's axis is at the hypothetical centre of its own light wave, meaning that the light bulb B will be at the centre of the light wave, and the light bulb A will not be at the centre of the light wave(figure 3,B).
Due to the rotation of the Earth the light bulb A is moving towards the East, and the result is that it will not be at the hypothetical centre of its own light wave(figure 3,B)!!!
(The figures 3,A & 3,B depict how the situation will look like if we are above the two light bulbs and we are looking down towards the surface of the Earth.
The two light bulbs are passing the one next to the other in our line of sight.
If the two light bulbs are the one in front of the other in our line of sight at the moment they will emit light, the situation will look like the figure G.)
Conclusions.
We can say that there is isotropy of the speed of light relative to a source only when the source is at the hypothetical centre of the light wave!!!!!!
The light bulb B(figure 3, B) is at the hypothetical centre of its own light wave which means that there is isotropy of the speed of light relative to this source!!!
The fact that the light bulb A(figure 3, B) is not at the hypothetical centre of its own light wave, means that there is anisotropy of the speed of light relative to this specific light source!!!!!!
But, this anisotropy is not the result of a different motion of the light that it is emitted from the light bulb A!!!!!!!
On the contrary, the light emitted from the light bulb A is making the exact same motion with the light emitted from the light bulb B, and that's why the two waves of light which are produced by the two light bulbs are expanding with exactly the
same way(figure 3, B)!!!!!
But, in order to say which is the relative speed between the photons and the light bulbs, we must focus on what the photons are doing in relation to the light bulbs, and not on what the photons are doing relative to each other!!!
All the photons that the light bulb A emits are making the same motion but not relative to the light bulb A, but relative to something else!!!!!!!!!
The light bulb A has emit photons towards all directions, but as we see on the figure 3,B , the photons that are emitted towards the East are closer to the light bulb A than the photons emitted towards the West, which means that we must say that the relative speed between the light bulb A and the photons moving towards the East is smaller than the relative speed between the light bulb A and the photons moving towards the West!!!!
Important note:
If we say that the time on the light source is slower or faster it makes no difference, because the fact that remains is that as the photons that the source has emit are moving away from the source they are not all at the same distance from the source!!!
The figures 2 & 3(3,A - 3,B) are helping us to understand what the figure 1 shows.
If we say that there is anisotropy of the speed of light relative to its source, that statement does not contradict to the fact that the motion of light does not depend on the motion of the source!!!!!!!!!
The photons emitted by the two light bulbs are making the same motion(figure 3,B), but what we will regard as relative speed between the light bulbs and the photons is a different thing!!!!
On the example in the figures 2 & 3,B the light bulb A is making revolutionary motion around the axis of the Earth!!!
If the light bulb A was making linear motion the result would have been the same!!!
Imagine a scenario where the two light bulbs are in relative motion with each other at constant relative speed but the light bulb A is not making revolutionary motion!!!
Imagine that the light bulb A is making linear motion and is coming from far away from the Earth, it will pass next to the light bulb B and will move away from the Earth.
In this scenario we would have two light bulbs in relative motion with each other and both of them being in an inertial reference frame, but the result would be the same, the light bulb A will again not be at the centre of its own light wave, meaning that it will happen again what we see in the figure 3, B!!!
What about the "Sagnac effect", one may ask???
Suppose that the light from the two light waves of our example(figures 2 - 3,B) travels around the planet.
The light emitted towards the West will return to the light bulbs/sources from the East, after it travels around the planet, and the light emitted towards the East will return to the light bulbs/sources from the West, after it travels around the planet!!!!
The two light waves will move in the same way traveling around the planet!!!
The photons that are emitted towards the West will return from the East to the light bulb B simultaneously with the photons that are emitted towards the East and will return to the light bulb from the West.
This means that we have photons which are emitted by the light bulb B, and these are photons that all are emitted simultaneously by the light bulb B, and they will return back to it simultaneously after they travel around the planet, meaning that we must say that these photons were having the same speed relative to the light bulb B!!!
I'm saying that the photons are emitted simultaneously by the source because they are part of the same light wave!!!
But, the photons which are emitted by the light bulb A, and these are photons that all are emitted simultaneously by the light bulb A, will not return simultaneously to the light bulb A after they travel around the planet, and this means that we must say that these photons are not having the same speed relative to the light bulb A!!!!
This will happen because the light bulb A does not remain at the centre of the light wave(figure 3, B) because it is moving towards the East due to the rotation of the Earth!!!
The photons that are emitted towards the West, will return from the East to the light bulb A before the photons that are emitted towards the East and will return to the light bulb A from the West, and these are photons which all are emitted simultaneously by the light bulb A because they are part of the same wave!!!
The fact that the photons will not return simultaneously to the light bulb A, even though they all are emitted simultaneously by the light bulb A(the same with the light bulb B), and even though they will travel on the same path, means that we must say that the photons are not having the same speed relative to the light bulb A!!!
The people who believe that the theory of relativity is correct will argue that the motion of all the photons is the same and the different result for the two light bulbs is due to their different motion!!!
I agree with that!!!!!!
It is a combination of the motions of the light bulbs and the photons, but this is what we are focusing on!!!
The photons emitted by the two light bulbs/sources will make identical motion, but due to the different motion of the light bulbs we have different results for the two light bulbs!!!
Due to the different motion of the light bulbs/sources, the result is that the one light bulb remains at the centre of its own light wave but the other light bulb does not remain at the centre of its own light wave(figure 3,B)!!!!!
This is anisotropy, and the result of the anisotropy is the "Sagnac effect"!!!!!
The light that is emitted towards the West will return to the light bulb B simultaneously with the light emitted towards the East, after they travel around the Earth, because the light bulb B is at the centre of the light wave!!!
But, the light that is emitted towards the West will not return to the light bulb A simultaneously with the light emitted towards the
East, after they travel around the Earth, because the light bulb A is moving towards the East due to the rotation of the Earth and it is not at the centre of the light wave, as the figure 3,B shows!
All the photons that the light bulb A emits are making the same motion not relative to the light bulb A, but relative to something else!!!!!
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Why what we see on the figure 3(3,A - 3,B) is happening?????This is happening because the motion of the photons in the vicinity of the Earth is affected & determined by the gravity of the Earth!!!!!
The motion of the photons that are emitted by the light bulbs A & B will be the same(figures 2, 3), but their motion is also affected by the gravity of the Earth, and that's why the light waves created by the two light bulbs are expanding in the same way.
So, the photons that the two light bulbs/sources emit are making the same motion inside the gravitational field of the Earth!!!
The light bulb A is on the move inside the gravitational field due to the rotation of the Earth, and it will not be at the hypothetical centre of its own light wave!!!
The light bulb B is stationary inside the gravitational field of the Earth because it does not revolve around the Earth's axis, and it will be at the hypothetical centre of the light wave!!!
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On the figures 3,A & 3,B we have seen how the situation will look like if the two light bulbs/sources emitting the light as a wave towards all directions.
Next, we will see a little different scenario that maybe will be helpful to some people.
So next, on the figures 3,C & 3,D , we will see again the same case that we see in the figures 3,A & 3,B , but now we will see how the situation will look like if the the two light bulbs/sources emit a few photons, and specifically we will see a situation where the two light bulbs/sources will emit four photons, one towards the East, one towards the West, one towards the North and one toward the South.
So, what happens is that at the moment that the light bulb A is next to the light bulb B(figure 3, C), each light bulb will emit one photon with a direction towards the East, one photon with a direction towards the West, one photon with a direction towards the North, and one photon with a direction towards the South.
Therefore, there will be two photons moving towards each direction(figure 3, D), one emitted by each light bulb, and these two photons will practically be stationary relative to each other, because they will move in exactly the same way!!!
(The figures 3,C & 3,D depict how the situation will look like if we are above the two light bulbs and we are looking down towards the surface of the Earth. The two light bulbs are passing the one next to the other in our line of sight.)
Figures 3, C & 3, D. Presents the same scenario that we see in the figures 3, A & 3, B, but here the two light bulbs/sources emit only four photons.
The light bulb B is a few centimetres above the ground and does not revolve around the axis of the Earth, meaning that it is stationary on the ECI reference frame.
When the light bulb A passes next to the light bulb B(figure 3, C), both light bulbs will emit four photons towards the four points of the horizon.
The light bulb B is a few centimetres above the ground and does not revolve around the axis of the Earth, meaning that it is stationary on the ECI reference frame.
When the light bulb A passes next to the light bulb B(figure 3, C), both light bulbs will emit four photons towards the four points of the horizon.
Two significant observations on the figure 3, D:
First: the photons that are emitted towards the East are closer to the light bulb A than the photons that are emitted towards the West!!!
Second: the light bulb B is in-line with the photons moving towards the North and the South, but the light bulb A is not
in-line with these photons!!!
On this example that I present here the light bulb A is revolving around the axis of the Earth.
If instead of this the light bulb A is making a linear motion and is coming from a location away from the Earth, passes close to the surface and then is moving away from the Earth, the result will be the same!!!
It makes no difference whether we have a rotational/revolutionary motion or a linear motion!!!
As we see in the figure 3,D the photons emitted towards the East are closer to the light bulb A than the photons that are emitted towards the West, and the result of that is the "Sagnac effect", meaning that due to the fact that the photons emitted towards the West are further away from the light bulb A, they will reach the light bulb A before the photons that are emitted towards the East, after all the photons revolve around the planet!!!
The fact that the photons that are emitted towards the East are closer to the light bulb A than the photons emitted towards the West means that the we must say that the relative speed between the photons emitted towards the West and the light bulb A
is larger that the relative speed between the photons emitted towards the East and the light bulb A!!!
As we see on the figure 3,D , the photons emitted towards the East and the photons emitted towards the West are having the same distance from the light bulb B, meaning that there is isotropy of the speed of light for this light bulb.
Next we will see more examples that will help us understand.
Example figures 4, 5, 6 & 7.
We place a light bulb on the North Pole at the point where the Earth's axis of rotation meets the surface(figure 4).
That light bulb is the light bulb A(figure 4).
That light bulb is the light bulb A(figure 4).
The light bulb A is stationary on the "Earth-centered-inertial"(ECI) frame.
At some point the light bulb A emits light towards all directions, or in other words we can say that a ''wave of light'' is emitted by the light bulb.
( Instead of ''wave of light'' we can call it ''expanding bubble of light'' or ''expanding group of photons'' because the light bulb emits photons towards all directions, meaning that it will be a three-dimensional wave! Of course on the pictures we see two-dimensional waves! )
( Instead of ''wave of light'' we can call it ''expanding bubble of light'' or ''expanding group of photons'' because the light bulb emits photons towards all directions, meaning that it will be a three-dimensional wave! Of course on the pictures we see two-dimensional waves! )
The light bulb A will be located at the hypothetical centre of the wave of light(figure 5).
( The figure 5 shows how the situation would look like if we were above the North Pole and we are looking down towards the surface of the Earth.)
( The figure 5 shows how the situation would look like if we were above the North Pole and we are looking down towards the surface of the Earth.)
Figure 5 shows how the situation would look like if we were above the North Pole and we are looking down towards the surface of the Earth.
The light bulb A is stationary at the point where the Earth's axis of rotation meets the surface, as we see on the figure 4.
Next let's imagine a little different situation.
Again we have the light bulb A that we have placed on the North Pole at the point where the axis of rotation meets the surface, as we see on the figure 4.
But now, let's add another light bulb in the picture.
Suppose that another light bulb, the light bulb B, is moving towards the light bulb A(figure 6,a).
There are various different ways to see the motion of the light bulb B:
One way is to say that the light bulb B rotates/revolves/orbits around the Earth by going from the South Pole to the North Pole.
In that case, the light bulb B is revolving around the Earth in a similar way with a light bulb which is stationary in the surface of the Earth on the equator(like the light bulb A on the figures 2 & 3), with the difference being that the light bulb on the equator is stationary relative to the surface.
Another way is to say that the light bulb B is making a linear motion and is coming from a location away from the Earth, it will pass close to the surface and next to the light bulb A, and it will move away from the Earth.
{ It makes no difference whether the light bulb B is revolving around the planet or if it makes a linear motion, in both case the light bulb B will not be at the centre of its own light wave, meaning that the fact that the light bulb will not be at the centre of its own light wave has nothing to do with the rotational/revolutionary motion or with the acceleration caused by it!!}
But now, let's add another light bulb in the picture.
Suppose that another light bulb, the light bulb B, is moving towards the light bulb A(figure 6,a).
There are various different ways to see the motion of the light bulb B:
One way is to say that the light bulb B rotates/revolves/orbits around the Earth by going from the South Pole to the North Pole.
In that case, the light bulb B is revolving around the Earth in a similar way with a light bulb which is stationary in the surface of the Earth on the equator(like the light bulb A on the figures 2 & 3), with the difference being that the light bulb on the equator is stationary relative to the surface.
Another way is to say that the light bulb B is making a linear motion and is coming from a location away from the Earth, it will pass close to the surface and next to the light bulb A, and it will move away from the Earth.
{ It makes no difference whether the light bulb B is revolving around the planet or if it makes a linear motion, in both case the light bulb B will not be at the centre of its own light wave, meaning that the fact that the light bulb will not be at the centre of its own light wave has nothing to do with the rotational/revolutionary motion or with the acceleration caused by it!!}
Figure 6,a. The light bulb B is moving towards the light bulb A.
The light bulb A is stationary at the point where the Earth's axis of rotation meets the surface, as we see on the figure 4.
The Figure 6,a shows how the situation will look like if we are above the North Pole and we are looking down towards the surface of the Earth.
When the light bulb B passes next to the light bulb A(figure 6), both light bulbs will emit light towards all directions.
Two light waves will be created, one from the photons that are emitted by the light bulb A, and one from the photons that are emitted by the light bulb B(figure 7).
Two light waves will be created, one from the photons that are emitted by the light bulb A, and one from the photons that are emitted by the light bulb B(figure 7).
( Figures 6 & 7 are showing how the situation would look like if we were above the North Pole and we were looking down towards the surface of the planet.)
The light bulb A is stationary at the point where the Earth's axis of rotation meets the surface, as we see on the figure 4.
The Figure 6 shows how the situation will look like if we are above the North Pole and we are looking down towards the surface of the Earth.
The Figure 6 shows how the situation will look like if we are above the North Pole and we are looking down towards the surface of the Earth.
The two waves of light will expand with exactly the same way(figure 7), even though the two light bulbs are in relative motion with each other, because the motion of light does not depend on the motion of the source!!!!!!!!!
Not only the motion of light does not depend on the motion of the source, but moreover, the photons which are emitted from the two light bulbs will make identical motion!!!!!!!!
Not only the motion of light does not depend on the motion of the source, but moreover, the photons which are emitted from the two light bulbs will make identical motion!!!!!!!!
Figure 7. The light bulb A is stationary at the point where the Earth's axis of rotation meets the surface, like we see on the figure 4.
The light bulb B will not be at the hypothetical centre of its own light wave.
The Figure 7 shows how the situation will look like if we were above the North Pole and we were looking down towards the surface of the Earth.
The figures 7,(a) & 7,(b) are showing only parts of the light waves that we see in the figure 7 in order to focus on the distances between the sources and the wavefronts.
Figure 7,(b). The Distance C is larger than the Distance D meaning that some of the photons that the light bulb B has emit
are closer to the source and some other photons are farther away from the source.
are closer to the source and some other photons are farther away from the source.
So, on the figure 7 example the facts are that the two light waves will expand in the same way and the two light bulbs are in relative motion with each other, therefore, if the light bulb A is at the centre of the light wave that it has emit, this means that the light bulb B will not be at the hypothetical centre of the light wave that it has emit(figure 7)!!!!!!
We cannot have both light bulbs at the hypothetical centre of the wave of light that they have emit, because the two light bulbs are on the move relative to each other, but the two light waves will expand in the same way!!!!!
Only the one of the light bulbs can be at the centre of the light wave!!!!!
The two waves of light will expand in the same way, and in other words we can say that the two light waves are stationary relative to each other(figure 7)!!!!!
Only the one of the light bulbs can be at the centre of the light wave!!!!!
The two waves of light will expand in the same way, and in other words we can say that the two light waves are stationary relative to each other(figure 7)!!!!!
Therefore, because the two light bulbs are in relative motion with each other, if the light bulb A is at the centre of the light wave, this means the the light bulb B will not be at the hypothetical centre of the light wave(figure 7)!!!
The only other option that we have is to say that both light bulbs are not at the centre of their light wave, but we cannot say that both light bulbs are at the centre of their light wave!!!!!!!!!!
The only other option that we have is to say that both light bulbs are not at the centre of their light wave, but we cannot say that both light bulbs are at the centre of their light wave!!!!!!!!!!
The light bulb A(figure 7) is at the centre of the light wave because it is at rest inside the gravitational field of the Earth, like a light bulb which is not rotating/revolving around the Earth's axis is also at rest inside the gravitational field( see example figures 2-3)!!!!
By being stationary at the point where the axis of rotation meets the surface, the light bulb A remains stationary inside the gravitational field of the Earth!!
The light bulb B(figure 7) is not at the centre of its own light wave because it is on the move inside the gravitational field of the Earth, like a light bulb which is stationary on the equator is on the move inside the gravitational field of the Earth due to the Earth's rotation(see example figures 2-3)!!!!
The figures 7,(a) & 7,(b) are helping us to understand because we see only parts of the light waves that we see in the figure 7, and we focus on the distance between the light bulbs and the photons.
On the figure 7,(b) we see that the distance C is larger than the distance D, and this means that we must say
that the relative speed between the light bulb B and the photons that are emitted towards the one direction is larger than the relative speed between the light bulb B and the photons that are emitted towards the other direction!!!
But, that different relative speed is not the result of a different motion of the photons, on the contrary, all the photons that are emitted by the light bulbs A & B are making the same motion, but they are making the same motion inside the gravitational field they are in, which in this case is the gravitational field of the Earth!!!!!
If we say that the time on the light bulb B is slower, it makes no difference to the fact that as the photons that are emitted by the light bulb B are moving away from the source, they are not all the photons at the same distance from the light bulb B!!!
Any source of light which is stationary on the surface of the Earth and away from the point where the Earth's axis of rotation meet the surface, it is not at the centre of the light wave that it has emit, because it is on the move inside the gravitational field of the Earth due to the Earth's rotation!!!
......................................................................................................................................................................................................................
As you have probably understand so far, i'm talking about the one-way speed of light!!!!
But wait a moment, when we are talking about the speed of an object relative to another object, regardless if these objects are photons, electrons, protons, cars, planets or anything else, we are referring to the one-way relative speed!!!
The "one-way speed" is what we call "SPEED"!!!
When we are talking about the relative speed between two cars, we are talking about the one-way relative speed, and when we are talking about the relative speed between fast moving muons and the Earth, we are also talking about the one-way relative speed!!!
What about the two-way speed of light, one may ask???
On the example on the figures 7,(a) & 7,(b) we see that the one-way speed of light relative to the light bulb B on the two opposite directions is not the same because some photons are closer to the source and some photons are farther away from the source!!!
But even though this is what is happening, the two-way speed of light relative to the light
bulb B will be the same for the two opposite directions!!!!
In order to see how this is happening we have to see the next example!!!
For the next example I will use a hypothetical case where a source emits light towards two opposite directions, and as the light is moving away from the source, the light that is moving towards the one direction is at twice the distance away from the source compared with the distance between the source and the light moving towards the other direction!!!
The figure M depicts a situation like this.
Imagine that our light source is a normal light bulb, but we have put covers around it so that the light that it emits is not spreading towards all directions, but instead is spreading only towards two opposite directions.
( Of course, when the light bulb is switched-on it will start emitting the light towards all directions simultaneously.)
Figure M. The source emits light towards two opposite directions, and if we compare the distances between the source and the light waves
on the two directions we will see that the distance A is twice the distance B.
Let's see the example.
We have the light source(light bulb) that we talk about earlier and we also have two reflectors(mirrors) in our possession, the reflectors 1 & 2.
We place the source exactly between the two reflectors, which means that the two reflectors are at the same distance from the source(figure N,1).
Light source and reflectors are stationary relative to each other.
At some point we switch-on the light source and it starts to emit light, but because we have put covers in specific places around the light source the light is moving towards the two opposite directions where the reflectors are placed.
The figure N,1 depicts this moment, meaning that it depicts the moment of the emission of light by the source(light bulb), and we see the two light waves just starting to move away from the source.
Figure N, 1. The moment of the emission of light by the source. Two light waves starting to move away from the source and towards the two reflectors.
As I have said earlier, the light wave that is moving towards the one direction is at twice the distance away from the source compared to the distance between the source and the light wave moving towards the opposite direction!!!
Specifically, the light wave that is moving with a direction towards the reflector 1 is the one that is at twice the distance away from the source compared to the distance between the source and the light wave moving towards the reflector 2(figure N, 2).
Since the reflectors are stationary relative to the light source, the motion of the light waves relative to the source is also a motion relative to the reflectors!!!
So, it is very important to realise that we have a situation where relative to the source and the reflectors, the light wave moving with a direction from the reflector 2 to the reflector 1 is making twice the distance that the light wave moving with a direction from the reflector 1 to the reflector 2 is making(figure N, 2)!!!
This is very important to realise and we will need it again!!!
(This is the motion of the light relative to the specific source and reflectors, and only relative to them or any other object stationary relative to them.)
A very important note:
If the light wave that is moving towards the reflector 2 reflect somewhere and start to move towards the opposite direction meaning towards the reflector 1, it will make similar motion with the other light wave because they will be moving towards the same direction!!!
It's the direction of motion of the light that determines towards which direction the motion will be larger!!!
(I'm talking about the motion of the light waves relative to the source and the reflectors.)
If both light waves reflect somewhere and their directions of motion are reversed the thing that will also be reversed is which light wave will make larger motion relative to the source and the reflectors, because the fact that determines which light wave makes the larger motion is the direction of motion of the wave, and the light wave moving with a direction from the reflector 2 towards the reflector 1 will make twice the distance that the light wave moving with a direction from the reflector 1 to the
reflector 2 is making.
Now, the light wave that is reflected to the reflector 2 will move towards the opposite direction, meaning that it will move towards the reflector 1(figure N,5), and now we have again two light waves moving towards opposite directions as we were having earlier, but now the direction of motion of the light waves is reversed and so the motion of the light waves relative to the source and the reflectors is reversed!!!
As I have said earlier, the thing that determines the extent of the motion of the light waves relative to the source and the reflectors is the direction of motion, and the light wave that has direction of motion from the reflector 2 towards the reflector 1 will make twice the distance that the light wave moving from the reflector 1 towards the reflector 2 will make!!!
So now, the light wave that is reflected to the reflector 2 is moving towards the reflector 1(and the source), meaning that now this light wave will make twice the distance that the other light wave is making because the other light wave is moving from the reflector 1 towards the reflector 2(and the source) after its reflection to the reflector 1 (figures N, 5 & N, 6)!!!
The final result will be that the two light waves will return to the source simultaneously, as we can see on the figure N, 6!!!
So, what do we have on this example/experiment???
We have a source of light and two reflectors stationary at the same distance away from the source but at opposite directions.
The source emits light, and that light returns to the source simultaneously after it is reflected to the reflectors!!!
Since the two light waves have travel the same distance and since they will return to the source simultaneously, the source(a human on the source) thinks that the speed of the two light waves relative to the source was the same, but the one-way speed of light was not the same, only the two-way speed was the same!!!
The "Sagnac effect" is the result of the one-way anisotropy of the speed of light!!!
So, we see that even though the one-way speed of light relative to the source is different we end up with the same two-way relative speed for the two opposite directions!!!
When the two light waves are moving towards the same direction(from figures N,3 - P,3 to figures N,4 - P,4) they are making the same motion(the percentage that we see in the figures N,4 - P,4) relative to the source and the reflectors.
When both light waves have been reflected to the reflectors and their direction of motion is reversed compared to their motion prior to their reflection(from figures N,4 - P,4 to figures N,6 - P,6), also their percentage of motion relative to the source and the reflectors is reversed compared to their motion prior to their reflection that we see in the figures N,3 - P,3.
The light bulbs A & C, which are on the planet Earth, are in relative motion with each other which means that there cannot be both light bulbs at the centre of their own light wave!!!
So, the light bulb C is not at the centre of its own light wave.
{ What happens on the planet Earth i have explain it in the example with the figures 4, 6 & 7. }
Question:
The light bulb B is stationary relative to the light bulb C, therefore you expect that what happens to the one light bulb
also happens to the other, so why the light bulb B is at the centre of its own light wave, unlike with what happens to the
light bulb C which is not at the centre of its own light wave{figure 9,(B)}??????
Answer:
The light bulb B is at the centre of its own light wave because it is on another planet and it is stationary inside the gravitational field of that planet!!!!
On the figure 9,(B) we see that the light bulbs A & B are in relative motion with each other but both are at the centre of their own light wave, unlike with what happens in the relative motion between the light bulbs A & C where the light bulb C is not at the centre of its own light wave!!!!
Why that happens???
The light bulb C which is on the move relative to the light bulb A is not at the centre of its own wave, so why the light bulb B which is also on the move relative to the light bulb A is at the centre of its own wave???
The light bulb B is at the centre on its own light wave for the same reason why the light bulb A is also at the centre of its own light wave, regardless if they are in relative motion with each other.
The reason is that the light bulb A is stationary inside the gravitational field of the planet Earth, and the light bulb B is stationary inside the gravitational field of the planet Mars(figure 8), and the fact that they are in relative motion with each other doesn't matter!!!!!
The reason why the light bulb C is not at the centre of its own light wave although it is stationary relative to the light bulb B
which is at the centre of its own light wave, is because the light bulb C is on a different planet and it is on the move relative to the gravitational field of that planet!!!!!!
The light bulb B is inside the gravitational field of the planet Mars and is not moving inside that field, and the light bulb C is inside the gravitational field of the Earth, but the light bulb C is on the move inside that gravitational field!!!!
(The light bulb C is stationary relative to the planet Mars and the light bulb B, but it is on the move relative to the planet Earth and the light bulb A because the planets Earth and Mars are in relative motion with each other)
Let's add another light bulb on our example.
Let's say that at the moment that the light bulb B emits light, on Mars there is also the light bulb D{ figure 9,(C) }.
The light bulb D is stationary relative to the Earth and the light bulb A, which means that it is on the move relative to the Mars and the light bulb B.
At the moment that the light bulb B emits light, the light bulb D passes next to it and it also emits light.
Two light waves will be created, one from the light emitted by the light bulb B and the other from the light emitted by the light bulb D{ figure 9,(C) }, and the two light waves will expand in exactly the same way.
The two light waves will expand exactly the same, but the light bulbs B & D are in relative motion with each other, meaning that only the one of the two light bulbs can be at the centre of its own wave!!!
The light bulb D will not be at the centre of its own light wave{ figure 9,(C) }, even though it is stationary relative to the Earth and the light bulb A!!!!!!
So, we will have the light bulbs A & D stationary relative to each other, and the light bulb A will be at the centre of its own light wave but the light bulb D will not be at the centre of its own light wave!!!!!!
That will happen because the light bulb D is inside the gravitational field of the planet Mars and it is one the move inside that field, but the light bulb A is inside the gravitational field of the planet Earth and it is stationary inside that field!!!
As the figure Z shows, when the light that the light bulb(light source) has emit is away from the Earth, the light bulb will stop being at the centre of the light wave because the gravity of the Earth affects less and less the motion of the photons!!!!!
When the light is away from the Earth, the influence of the Earth's gravity becomes weaker and weaker, and the influence from the gravitational fields of other objects becomes stronger!!!
As you can understand from the figure Z, if we regard the whole planet as a source of light, the planet is not at the centre of the light wave!!!!!
So, why both the light bulb C and the light bulb D will not be at the centre of their own light wave???
The light bulbs C & D are on the move relative to each other, and because the two light waves that they have emit will expand in the same way, the possibility for both the light bulbs C & D to be at the centre of the light wave does not exist, which means that there are the following two possible realities:
First possible reality: both light bulbs will not be at the centre of the expanding light waves.
Second possible reality: only the one of the light bulbs will be at the centre of the expanding light waves.
The correct answer is that both the light bulb C and the light bulb D will not be at the hypothetical centre of the expanding wave of light that they have emit, because as you can understand, on the example in the figure 11(B), if we say that the one of the two light bulbs will be at the centre of the expanding wave of light, we must explain which of the two and why????
For example, if someone says that the light bulb C will be at the centre of the expanding light wave, this means that the light bulb D will not be at the centre of the expanding light wave, but why the light bulb C and not the light bulb D???
If someone says something like that because he will think that it is the right answer due to the fact that the light bulb C is stationary relative to the Earth, this is a wrong way of thinking because the Earth is just another planet like Mars, and the light bulb D is stationary relative to Mars, so why the light bulb C and not the light bulb D???
So, what does this mean?????
It means that the probability for a light source which is in the open space away from a planet to be at the hypothetical centre of the light wave that it will emit, is extremely small!!!!!!!
So, a light source away from a planet probably will not be at the centre of the light wave that it will emit, and this means that we must say that there is anisotropy of the speed of light relative to this source, but, the photons emitted by this source are moving in the same way with the photons which are emitted by other sources in the same area, regardless of the motion of these other sources, because the motion of light does not depend on the motion of the source!!!!!
As we see in the figure 11(B), the photons emitted by the light bulb C are moving in the same way with the photons emitted by the light bulb D.
{ What happens to the light bulbs on the planets i have explain it on the previous examples(figures 7 - 9)}
The light bulb C is stationary relative to the light bulb A, so why it does not happening the same thing on the two light bulbs, meaning why the light bulb C is not at the centre of the light wave but the light bulb A is at the centre of the light wave?????
The reason why the light bulb A is at the centre of the light wave is because it is stationary inside the gravitational field of the Earth!!!!
The normality for a light source away from a planet(like the light bulb C) is that the source is not at the centre of the light wave that it will emit!!!!!
The probability for a light source in the open space away from a planet(like the light bulb C) to be at the hypothetical centre of its own light wave, is extremely small!!!
But the same happens to a light source on a rotating planet, meaning that the probability for a light source on a rotating planet to be at the centre of the light wave is extremely small, because in order for that to happen the source must be stationary inside the gravitational field of the planet, meaning that the source must not revolve around the planet's axis!!!!!
On the figure 11(B) we see two-dimensional light waves, meaning circular waves, but of course the sources emit
three-dimensional waves, meaning spherical waves, because they emit light towards all directions, but I cannot
depict that!!!
As you can understand from the example in the figure 11(B), if we are away from the planets and we regard the whole planet Earth or the whole planet Mars as a source of light, it will happen the same thing that happens with the light bulbs C & D, and i mean that the planets will not be at the centre of the light wave when the photons are away from the planet and the influence of the planet's gravity is weak(see also figure Z on the previous example)!!!!!!
If a planet is not rotating, a light source which is stationary in the surface of the planet, will be at the centre of its own light wave regardless of where it is located{ I'm talking about what happens while the photons are close to the planet(see figure Z on the previous example) }.
But, most of the planets are rotating, and a light source stationary on the equator of a rotating planet is not at the centre of its own light wave.
A light source which is stationary inside the gravitational field of the Earth, meaning stationary on the ECI frame, is a the centre of its own light wave only if is very close to the surface, where the gravity is strong.
If the light source is far away from the planet, even though it still is affected by the gravity of the Earth, and even if it is stationary on the "Earth-Centered Inertial"(ECI) frame, it will not be at the centre of its own light wave because the influence of the Earth's gravity is weak!!!
It depends on how close to the planet is the source.
What i mean is that a light source which is away from the Earth, even if it is stationary on the ECI frame, it will not be at the centre of the light wave that it will emit, because the motion of the light that this source will emit is affected by various gravitational fields other than the Earth's.
Let's take the light bulb A for example{ figures 10-11(B) }.
If the light bulb A starts to move away from the planet, even if it still remains at rest on the ECI frame, when it will be away from the Earth and the influence of the gravity of the Earth is weak, if it will emit light the light bulb A will not be at centre of the light wave, because the motion of the light that this source will emit will be affected by various other gravitational fields!!!
When a source is very close to the Earth, the light that the source will emit it still is affected by other gravitational fields but the influence of the Earth's gravitational field prevails over the other gravitational fields!!!
The light bulb A{ figure 11,(B) } is in the surface of the planet Earth, and because it is stationary inside the gravitational field of the Earth, the light bulb A is at the centre of the light wave.
But, the Earth is just an object alone in the open space!!!
If the light bulb A was in the surface of an object much smaller than the Earth, probably would not have been in the centre of
An important explanation about the "doppler effect".
Some of you may think that there is a problem in what I'm saying because you may think that in the case where the light source is not at the hypothetical centre of its own light waves we must have doppler effect on a receiver, and maybe you will think that this must happen even if a receiver is stationary relative to the source, in the case where the light source is not at the hypothetical centre of its own light waves!!!
The answer to this is that there will be redshift & blueshift but not through the way that you think, and next I will explain what is happening!!!
Let's see the example.
Suppose that we have a light source and two receivers, and the source is placed exactly between the two receivers, as we see in the figure 12.
Light source and receivers are stationary relative to each other(figure 12).
At the beginning the light source does not emit anything, but at some point the light source will start to emit every second an electromagnetic signal/wave towards all directions.
This means that the source will not emit electromagnetic radiation(light) continuously, like the Sun or a light bulb does, but instead it will emit
electromagnetic radiation(light) every second for a very small duration of time, and in between the source does not emit anything.
You can call it electromagnetic wave or electromagnetic pulse or electromagnetic signal or light wave, but the important fact is that it is something that is not happening continuously, but instead it is radiation that is emitted every second by the source, and the rest of the time the source does not emit anything.
So, every time that the source emits radiation, a wave of light is created.
My idea(regarding the changes in the energy of the photons).
Changes on the energy of photons occur due to changes in the relative speed between photons and observers(maybe they also occur due to other reasons)!!!
( The "doppler effect" that is produced due to the relative motion between a receiver/detector and a light source that emits repeating light waves is produced through a different mechanism/process.
Idea: It seems to me that particles(photons, electrons, protons, etc,) don't actually have wavelength & frequency, but it is just something that we have attributed to them without actually having it!!!!!
There is a chance that some may misunderstood what I'm saying, so, I will clarify.
Another idea(related to gravitational blueshift & redshift).
On the examples in the figures 1, 2, 3, 4, 5, 6, 7, 8 & 9 we have seen how the situation will look like if we are above the surface of a planet and we are looking down towards the surface and a source of light is in our line of sight in front of the planet.
Next we will see how the situation will look like(how we will depict the situation) if we are away from a planet(but not too far away from it), and we are looking towards the planet(Earth) and a light source is next to it, and in our line of sight behind the light source is the empty space and not the surface of the planet(figures 16-17).
According to the humans on the planet(Earth), this light source is some metres above the surface of the planet(at a higher altitude), but for us that we are away from the planet the source appears to be next to the planet(figures 16-17).
(In the pictures the Earth is small compared to the source and the detectors in order to fit in the pictures)
Suppose that we have a source of light located at some height above the surface of the Earth.
It can be 10 metres, or 100 metres, or 1000 metres above the surface, it doesn't really matter as long as it's not too far from the planet.
The light source is placed exactly between two detectors that can detect the photons that the source will emit(figures 16, 17).
The one detector is at lower altitude and the other detector is at higher altitude and the source is exactly between them(figures 16, 17).
An Explanatory example(regarding the changes in the energy of photons).
At the beginning of this paper(in the example with the figures A, B & C) we have seen that the light/photons always move in the same way regardless of the motion of the source.
At the moment that the one light wave have reach the reflector 1 and reflect on it, the other light wave will be at half the distance between the source and the reflector 2(figure N, 3).
The light wave that is reflected to the reflector 1 will start to move towards the source and the reflector 2, meaning that now the two light waves are moving towards the same direction, and due to that fact the two light waves will make similar motion relative to the source and the reflectors(from figure N,3 to figure N,4).
So, when the other light wave reach the reflector 2 and reflect on it, the other light wave will be exactly at half the distance between the reflector 1 and the light source on its journey back to the source(figure N, 4)!!!
Figure N, 3. When the one light wave is reflected to the reflector 1 the other light wave is at half the distance between the source and the reflector 2.
Figure N, 4. When the one light wave is reflected to the reflector 2 the other light wave is at half the distance between the reflector 1 and the source.
Now, the light wave that is reflected to the reflector 2 will move towards the opposite direction, meaning that it will move towards the reflector 1(figure N,5), and now we have again two light waves moving towards opposite directions as we were having earlier, but now the direction of motion of the light waves is reversed and so the motion of the light waves relative to the source and the reflectors is reversed!!!
As I have said earlier, the thing that determines the extent of the motion of the light waves relative to the source and the reflectors is the direction of motion, and the light wave that has direction of motion from the reflector 2 towards the reflector 1 will make twice the distance that the light wave moving from the reflector 1 towards the reflector 2 will make!!!
So now, the light wave that is reflected to the reflector 2 is moving towards the reflector 1(and the source), meaning that now this light wave will make twice the distance that the other light wave is making because the other light wave is moving from the reflector 1 towards the reflector 2(and the source) after its reflection to the reflector 1 (figures N, 5 & N, 6)!!!
The final result will be that the two light waves will return to the source simultaneously, as we can see on the figure N, 6!!!
We have a source of light and two reflectors stationary at the same distance away from the source but at opposite directions.
The source emits light, and that light returns to the source simultaneously after it is reflected to the reflectors!!!
Since the two light waves have travel the same distance and since they will return to the source simultaneously, the source(a human on the source) thinks that the speed of the two light waves relative to the source was the same, but the one-way speed of light was not the same, only the two-way speed was the same!!!
The "Sagnac effect" is the result of the one-way anisotropy of the speed of light!!!
So, we see that even though the one-way speed of light relative to the source is different we end up with the same two-way relative speed for the two opposite directions!!!
We don't actually need all the pictures in order to describe what happens.
Basically there are three steps, and we see them in the figures N,3 - N,4 & N,6 that we see again below.
Figure N, 3. Light wave reflecting to the reflector 1.
Figure N, 4. Light wave reflecting to the reflector 2.
Figure N, 6. The two light waves returning to the source.
On this example(figures N,3 - N,4 - N,6) the one light wave makes 50 percent of the distance(relative to the source) that the light wave moving towards the opposite direction is making, but we can use whatever ratio of distances we want.
The end result always remain the same!!!
If, for example, the one light wave makes 90 percent of the distance that the other light wave is making, there will be no difference on the final result.
The end result again will be that the two light waves will return to the source simultaneously, and the figures P,3 - P,4 - P,6 present this case!!!
Figure P, 3. Light wave reflecting to the reflector 1.
Figure P, 4. Light wave reflecting to the reflector 2.
Figure P, 6. The two light waves returning to the source.
When the two light waves are moving towards the same direction(from figures N,3 - P,3 to figures N,4 - P,4) they are making the same motion(the percentage that we see in the figures N,4 - P,4) relative to the source and the reflectors.
When both light waves have been reflected to the reflectors and their direction of motion is reversed compared to their motion prior to their reflection(from figures N,4 - P,4 to figures N,6 - P,6), also their percentage of motion relative to the source and the reflectors is reversed compared to their motion prior to their reflection that we see in the figures N,3 - P,3.
Example figures 8 - 9. --Other Planets--
(On this next example we will use a similar situation with the example in the figures 4 - 6 & 7, but we will add the planet Mars on the example)
On Earth, we place a light bulb on the North Pole at the point where the Earth's axis of rotation meets the surface(figure 8).
And, we do a similar thing on the planet Mars.
So, on Mars, we place a light bulb on the North Pole at the point where the Mars's axis of rotation meets the surface(figure 8).
The light bulb on Earth is the light bulb A and the light bulb on Mars is the light bulb B{ figures 8 - 9,(A) & 9,(B) }.
At the period that our example/experiment is taken place, the planet Mars is moving away from the planet Earth.
( Earth and Mars, some times are moving closer to each other and some times are moving away from each other.)
On the planet Earth, there is another light bulb, the light bulb C{ figures 9,(A) - 9,(B) }.
The light bulb C is stationary relative to the planet Mars and the light bulb B, meaning that it is one the move relative to the light bulb A and the Earth!!!
At some point the light bulb C passes next to the light bulb A{ figure 9,(A) } because it is moving due to the fact that is stationary relative to the planet Mars.
So, on Mars, we place a light bulb on the North Pole at the point where the Mars's axis of rotation meets the surface(figure 8).
The light bulb on Earth is the light bulb A and the light bulb on Mars is the light bulb B{ figures 8 - 9,(A) & 9,(B) }.
At the period that our example/experiment is taken place, the planet Mars is moving away from the planet Earth.
( Earth and Mars, some times are moving closer to each other and some times are moving away from each other.)
On the planet Earth, there is another light bulb, the light bulb C{ figures 9,(A) - 9,(B) }.
The light bulb C is stationary relative to the planet Mars and the light bulb B, meaning that it is one the move relative to the light bulb A and the Earth!!!
At some point the light bulb C passes next to the light bulb A{ figure 9,(A) } because it is moving due to the fact that is stationary relative to the planet Mars.
When the light bulb C is next to the light bulb A{ figure 9,(A) }, the light bulbs A, B & C will emit light towards all directions.
( Figures 9,(A) & 9,(B) are showing how the situation would look like if we were above the North Poles of the planets and we are looking down.)
( Figures 9,(A) & 9,(B) are showing how the situation would look like if we were above the North Poles of the planets and we are looking down.)
Figure 9,(A) shows how the situation would look like if we were above the North Poles of the planets looking down.
When the light bulb C is next to the light bulb A, all three light bulbs will emit light.
Mars is moving away from Earth.
When the light bulb C is next to the light bulb A, all three light bulbs will emit light.
Mars is moving away from Earth.
After the light bulbs A, B & C emit light, three light waves will be created, one from each light bulb{ figure 9,(B) }.
The light bulb A is located at the point where the axis of rotation meets the surface, and also the light bulb B is located at the point where the axis of rotation meets the surface, but they are in different planets!!!!!!!!
If the light bulb A is at the centre of its own light wave, the same must happen to the light bulb B!!!
Why will it be a different result on the planet Mars???
The light bulb B which is on Mars, will be at the centre of its light wave, similarly with what will happen to the light bulb A on Earth, because both light bulbs are at the point where the axis of rotation meet the surface{ figure 9,(B) }.
But, the light bulb C, although it is stationary relative to the light bulb B, will not be at the centre of its own light
wave{ figure 9,(B) }, as I have explain on the example with the figures 4, 6 & 7!!!!!
The light bulb A is located at the point where the axis of rotation meets the surface, and also the light bulb B is located at the point where the axis of rotation meets the surface, but they are in different planets!!!!!!!!
If the light bulb A is at the centre of its own light wave, the same must happen to the light bulb B!!!
Why will it be a different result on the planet Mars???
The light bulb B which is on Mars, will be at the centre of its light wave, similarly with what will happen to the light bulb A on Earth, because both light bulbs are at the point where the axis of rotation meet the surface{ figure 9,(B) }.
But, the light bulb C, although it is stationary relative to the light bulb B, will not be at the centre of its own light
wave{ figure 9,(B) }, as I have explain on the example with the figures 4, 6 & 7!!!!!
Figure 9,(B) shows how the situation would look like if we were above the North Poles of the planets looking down towards the surface.
Mars is moving away from Earth.
Mars is moving away from Earth.
The light bulb C is moving relative to the light bulb A because it is stationary relative to the planet Mars.
So, even though the light bulbs B & C are stationary relative to each other, meaning that they are making identical motion relative to the light bulb A, the result is not the same on the two light bulbs, because the light bulb B is at the centre of its own light wave but the light bulb C is not at the centre of its own light wave{ figure 9,(B) }!!!
The light bulbs A & C, which are on the planet Earth, are in relative motion with each other which means that there cannot be both light bulbs at the centre of their own light wave!!!
So, the light bulb C is not at the centre of its own light wave.
{ What happens on the planet Earth i have explain it in the example with the figures 4, 6 & 7. }
Question:
The light bulb B is stationary relative to the light bulb C, therefore you expect that what happens to the one light bulb
also happens to the other, so why the light bulb B is at the centre of its own light wave, unlike with what happens to the
light bulb C which is not at the centre of its own light wave{figure 9,(B)}??????
Answer:
The light bulb B is at the centre of its own light wave because it is on another planet and it is stationary inside the gravitational field of that planet!!!!
On the figure 9,(B) we see that the light bulbs A & B are in relative motion with each other but both are at the centre of their own light wave, unlike with what happens in the relative motion between the light bulbs A & C where the light bulb C is not at the centre of its own light wave!!!!
Why that happens???
The light bulb C which is on the move relative to the light bulb A is not at the centre of its own wave, so why the light bulb B which is also on the move relative to the light bulb A is at the centre of its own wave???
The light bulb B is at the centre on its own light wave for the same reason why the light bulb A is also at the centre of its own light wave, regardless if they are in relative motion with each other.
The reason is that the light bulb A is stationary inside the gravitational field of the planet Earth, and the light bulb B is stationary inside the gravitational field of the planet Mars(figure 8), and the fact that they are in relative motion with each other doesn't matter!!!!!
The reason why the light bulb C is not at the centre of its own light wave although it is stationary relative to the light bulb B
which is at the centre of its own light wave, is because the light bulb C is on a different planet and it is on the move relative to the gravitational field of that planet!!!!!!
The light bulb B is inside the gravitational field of the planet Mars and is not moving inside that field, and the light bulb C is inside the gravitational field of the Earth, but the light bulb C is on the move inside that gravitational field!!!!
(The light bulb C is stationary relative to the planet Mars and the light bulb B, but it is on the move relative to the planet Earth and the light bulb A because the planets Earth and Mars are in relative motion with each other)
Let's add another light bulb on our example.
Let's say that at the moment that the light bulb B emits light, on Mars there is also the light bulb D{ figure 9,(C) }.
The light bulb D is stationary relative to the Earth and the light bulb A, which means that it is on the move relative to the Mars and the light bulb B.
At the moment that the light bulb B emits light, the light bulb D passes next to it and it also emits light.
Two light waves will be created, one from the light emitted by the light bulb B and the other from the light emitted by the light bulb D{ figure 9,(C) }, and the two light waves will expand in exactly the same way.
The two light waves will expand exactly the same, but the light bulbs B & D are in relative motion with each other, meaning that only the one of the two light bulbs can be at the centre of its own wave!!!
The light bulb D will not be at the centre of its own light wave{ figure 9,(C) }, even though it is stationary relative to the Earth and the light bulb A!!!!!!
So, we will have the light bulbs A & D stationary relative to each other, and the light bulb A will be at the centre of its own light wave but the light bulb D will not be at the centre of its own light wave!!!!!!
That will happen because the light bulb D is inside the gravitational field of the planet Mars and it is one the move inside that field, but the light bulb A is inside the gravitational field of the planet Earth and it is stationary inside that field!!!
Figure 9,(C) shows how the situation would look like if we were above the North Poles of the planets looking down towards the surface.
Mars is moving away from Earth.
Mars is moving away from Earth.
The light bulb B is moving relative to the light bulb D because the light bulb D is stationary relative to the planet Earth.
Important note.
The figures 9,(B) - 9,(C) are showing which is the situation when the light from the light bulbs is very close to the planets Mars & Earth!!!
When the light is away from the planets, the light bulbs A & B{ figures 9,(B) - 9,(C) } will stop being at the centre of the light wave that they have emit, like we see on the figure Z below, because the light will be less and less affected by the gravity of the planets.
A light bulb(light source) which is stationary in the surface of the Earth at the point where the axis of rotation meets the surface, will be at the hypothetical centre of the light wave that it has emit, only while the light that it has emit is very close to the Earth.The figures 9,(B) - 9,(C) are showing which is the situation when the light from the light bulbs is very close to the planets Mars & Earth!!!
When the light is away from the planets, the light bulbs A & B{ figures 9,(B) - 9,(C) } will stop being at the centre of the light wave that they have emit, like we see on the figure Z below, because the light will be less and less affected by the gravity of the planets.
As the figure Z shows, when the light that the light bulb(light source) has emit is away from the Earth, the light bulb will stop being at the centre of the light wave because the gravity of the Earth affects less and less the motion of the photons!!!!!
When the light is away from the Earth, the influence of the Earth's gravity becomes weaker and weaker, and the influence from the gravitational fields of other objects becomes stronger!!!
As you can understand from the figure Z, if we regard the whole planet as a source of light, the planet is not at the centre of the light wave!!!!!
The next example reveals more!!!!!!!
Example figures 10 & 11. -Away From a Planet-
On Earth, we place a light bulb on the North Pole at the point where the Earth's axis of rotation meets the surface(figure 10).
And, we do a similar thing on the planet Mars.
So, on Mars, we place a light bulb on the North Pole at the point where the Mars's axis of rotation meets the surface(figure 10).
The light bulb on Earth is the light bulb A, and the light bulb on Mars is the light bulb B{ figures 10 - 11,(A) & 11,(B) }.
Earth and Mars, some times are moving closer to each other and some times are moving away from each other.
At the period that our example/experiment is taken place, Earth and Mars are moving towards each other!!!
Far away from the Earth there is the light bulb C(figure 10).
The light bulb C is stationary relative to the planet Earth and the light bulb A, and it is located between the planets Earth and Mars.
Far away from the Mars there is the light bulb D(figure 10).
The light bulb D is stationary relative to the planet Mars and the light bulb B, and it is located between the planets Mars and Earth.
As you can understand, the light bulbs C & D are in relative motion with each other.
As the two planets are moving closer to each other, also the light bulbs C & D are moving closer to each other(figure 10).
At some point, the light bulb C passes next to the light bulb D{ figure 11,(A) }.
When the light bulb C and the light bulb D are next to each other{ figure 11,(A) }, the light bulbs A, B, C & D will emit light towards all directions.
(The figures 11(A) & 11(B) are showing how the situation would look like if we were above the North Poles of the planets and we are looking down.)
And, we do a similar thing on the planet Mars.
So, on Mars, we place a light bulb on the North Pole at the point where the Mars's axis of rotation meets the surface(figure 10).
The light bulb on Earth is the light bulb A, and the light bulb on Mars is the light bulb B{ figures 10 - 11,(A) & 11,(B) }.
Earth and Mars, some times are moving closer to each other and some times are moving away from each other.
At the period that our example/experiment is taken place, Earth and Mars are moving towards each other!!!
Far away from the Earth there is the light bulb C(figure 10).
The light bulb C is stationary relative to the planet Earth and the light bulb A, and it is located between the planets Earth and Mars.
Far away from the Mars there is the light bulb D(figure 10).
The light bulb D is stationary relative to the planet Mars and the light bulb B, and it is located between the planets Mars and Earth.
As you can understand, the light bulbs C & D are in relative motion with each other.
As the two planets are moving closer to each other, also the light bulbs C & D are moving closer to each other(figure 10).
At some point, the light bulb C passes next to the light bulb D{ figure 11,(A) }.
When the light bulb C and the light bulb D are next to each other{ figure 11,(A) }, the light bulbs A, B, C & D will emit light towards all directions.
(The figures 11(A) & 11(B) are showing how the situation would look like if we were above the North Poles of the planets and we are looking down.)
Earth and Mars are moving towards each other.
Figure 11,(A). Depicts how the situation would look like if we were above the North Poles of the planets looking down.
When the light bulbs C & D are next to each other, all four light bulbs will emit light.
Earth and Mars are moving towards each other.
When the light bulbs C & D are next to each other, all four light bulbs will emit light.
Earth and Mars are moving towards each other.
So, what will happen is that the light bulbs A, B, C & D will emit light, and four expanding light waves will be created.
The figure 11,(B) shows which will be the situation a fraction of a second after the light has been emitted from the four light bulbs.
Figure 11,(B). Depicts how the situation would look like if we were above the North Poles of the planets looking down.
Away from a planet, both the light bulb C and the light bulb D will not be at the centre of their own light wave!!!
Earth and Mars are moving towards each other.
Away from a planet, both the light bulb C and the light bulb D will not be at the centre of their own light wave!!!
Earth and Mars are moving towards each other.
What we see in the figure 11,(B):
The light bulbs C & D will emit photons towards all directions.
There will be created two expanding waves of light, one from each light bulb.
The expanding light wave from the light bulb C is the orange one, and the expanding light wave from the light bulb D is the red one.
The expanding light wave from the light bulb C is the orange one, and the expanding light wave from the light bulb D is the red one.
The two waves of light that the light bulbs C & D have emit will expand with exactly the same way in space{ figure 11,(B) },
and both the light bulb C and the light bulb D will not be at the hypothetical centre of the light wave that they have emit!!!!!!!
So, why both the light bulb C and the light bulb D will not be at the centre of their own light wave???
The light bulbs C & D are on the move relative to each other, and because the two light waves that they have emit will expand in the same way, the possibility for both the light bulbs C & D to be at the centre of the light wave does not exist, which means that there are the following two possible realities:
First possible reality: both light bulbs will not be at the centre of the expanding light waves.
Second possible reality: only the one of the light bulbs will be at the centre of the expanding light waves.
The correct answer is that both the light bulb C and the light bulb D will not be at the hypothetical centre of the expanding wave of light that they have emit, because as you can understand, on the example in the figure 11(B), if we say that the one of the two light bulbs will be at the centre of the expanding wave of light, we must explain which of the two and why????
For example, if someone says that the light bulb C will be at the centre of the expanding light wave, this means that the light bulb D will not be at the centre of the expanding light wave, but why the light bulb C and not the light bulb D???
If someone says something like that because he will think that it is the right answer due to the fact that the light bulb C is stationary relative to the Earth, this is a wrong way of thinking because the Earth is just another planet like Mars, and the light bulb D is stationary relative to Mars, so why the light bulb C and not the light bulb D???
So, what does this mean?????
It means that the probability for a light source which is in the open space away from a planet to be at the hypothetical centre of the light wave that it will emit, is extremely small!!!!!!!
So, a light source away from a planet probably will not be at the centre of the light wave that it will emit, and this means that we must say that there is anisotropy of the speed of light relative to this source, but, the photons emitted by this source are moving in the same way with the photons which are emitted by other sources in the same area, regardless of the motion of these other sources, because the motion of light does not depend on the motion of the source!!!!!
As we see in the figure 11(B), the photons emitted by the light bulb C are moving in the same way with the photons emitted by the light bulb D.
{ What happens to the light bulbs on the planets i have explain it on the previous examples(figures 7 - 9)}
The light bulb C is stationary relative to the light bulb A, so why it does not happening the same thing on the two light bulbs, meaning why the light bulb C is not at the centre of the light wave but the light bulb A is at the centre of the light wave?????
The reason why the light bulb A is at the centre of the light wave is because it is stationary inside the gravitational field of the Earth!!!!
The normality for a light source away from a planet(like the light bulb C) is that the source is not at the centre of the light wave that it will emit!!!!!
The probability for a light source in the open space away from a planet(like the light bulb C) to be at the hypothetical centre of its own light wave, is extremely small!!!
But the same happens to a light source on a rotating planet, meaning that the probability for a light source on a rotating planet to be at the centre of the light wave is extremely small, because in order for that to happen the source must be stationary inside the gravitational field of the planet, meaning that the source must not revolve around the planet's axis!!!!!
On the figure 11(B) we see two-dimensional light waves, meaning circular waves, but of course the sources emit
three-dimensional waves, meaning spherical waves, because they emit light towards all directions, but I cannot
depict that!!!
As you can understand from the example in the figure 11(B), if we are away from the planets and we regard the whole planet Earth or the whole planet Mars as a source of light, it will happen the same thing that happens with the light bulbs C & D, and i mean that the planets will not be at the centre of the light wave when the photons are away from the planet and the influence of the planet's gravity is weak(see also figure Z on the previous example)!!!!!!
If a planet is not rotating, a light source which is stationary in the surface of the planet, will be at the centre of its own light wave regardless of where it is located{ I'm talking about what happens while the photons are close to the planet(see figure Z on the previous example) }.
But, most of the planets are rotating, and a light source stationary on the equator of a rotating planet is not at the centre of its own light wave.
A light source which is stationary inside the gravitational field of the Earth, meaning stationary on the ECI frame, is a the centre of its own light wave only if is very close to the surface, where the gravity is strong.
If the light source is far away from the planet, even though it still is affected by the gravity of the Earth, and even if it is stationary on the "Earth-Centered Inertial"(ECI) frame, it will not be at the centre of its own light wave because the influence of the Earth's gravity is weak!!!
It depends on how close to the planet is the source.
What i mean is that a light source which is away from the Earth, even if it is stationary on the ECI frame, it will not be at the centre of the light wave that it will emit, because the motion of the light that this source will emit is affected by various gravitational fields other than the Earth's.
Let's take the light bulb A for example{ figures 10-11(B) }.
If the light bulb A starts to move away from the planet, even if it still remains at rest on the ECI frame, when it will be away from the Earth and the influence of the gravity of the Earth is weak, if it will emit light the light bulb A will not be at centre of the light wave, because the motion of the light that this source will emit will be affected by various other gravitational fields!!!
When a source is very close to the Earth, the light that the source will emit it still is affected by other gravitational fields but the influence of the Earth's gravitational field prevails over the other gravitational fields!!!
The light bulb A{ figure 11,(B) } is in the surface of the planet Earth, and because it is stationary inside the gravitational field of the Earth, the light bulb A is at the centre of the light wave.
But, the Earth is just an object alone in the open space!!!
If the light bulb A was in the surface of an object much smaller than the Earth, probably would not have been in the centre of
its own light wave even if it was stationary inside the gravitational field of that object, because it depends on how strong is the gravitational field of the object!!!
The normality for a source of light away from a planet, is that the source will not be a the centre of the wave of light that it will emit.
In the case where the source is extremely close to a planet with a strong gravitational field, if that source is not rotating/revolving/orbiting around the planet, in that case the source will be at the centre of the light wave.
( A source of light stationary in the surface of a rotating planet, is rotating/revolving/orbiting around the planet, unless if it is at the point where the axis of rotation meet the surface.)
The normality for a source of light away from a planet, is that the source will not be a the centre of the wave of light that it will emit.
In the case where the source is extremely close to a planet with a strong gravitational field, if that source is not rotating/revolving/orbiting around the planet, in that case the source will be at the centre of the light wave.
( A source of light stationary in the surface of a rotating planet, is rotating/revolving/orbiting around the planet, unless if it is at the point where the axis of rotation meet the surface.)
On the figure 11(B), the light bulbs C & D are positioned symmetrically, but towards opposite directions, relative to the two expanding waves of light, but this in not what usually happens.
In most of the cases, the light bulbs C & D will not have the position that we see in the figure 11(B), but they will be located asymmetrically relative to the two expanding waves of light, and the asymmetry will be three-dimensional.
On the figure 11(B), the light bulbs C & D are having the same distance from the centre of their own wave of light, but this is done for demonstration purposes.
In most of the cases, the light bulbs C & D will not have the position that we see in the figure 11(B), but they will be located asymmetrically relative to the two expanding waves of light, and the asymmetry will be three-dimensional.
On the figure 11(B), the light bulbs C & D are having the same distance from the centre of their own wave of light, but this is done for demonstration purposes.
In the area where the light bulbs C & D are{ figure 11,(B) } there is influence of many gravitational fields.
The gravitational forces acting in that area are a mix of the gravity of the Sun, the gravity of the Earth, the gravity of Mars, the gravity of other planets, the gravity of the entire galaxy, etc.
These gravitational forces affect the motion of the photons that the light bulbs C & D emit!!!
The gravitational forces acting in that area are a mix of the gravity of the Sun, the gravity of the Earth, the gravity of Mars, the gravity of other planets, the gravity of the entire galaxy, etc.
These gravitational forces affect the motion of the photons that the light bulbs C & D emit!!!
An important explanation about the "doppler effect".
Some of you may think that there is a problem in what I'm saying because you may think that in the case where the light source is not at the hypothetical centre of its own light waves we must have doppler effect on a receiver, and maybe you will think that this must happen even if a receiver is stationary relative to the source, in the case where the light source is not at the hypothetical centre of its own light waves!!!
The answer to this is that there will be redshift & blueshift but not through the way that you think, and next I will explain what is happening!!!
Let's see the example.
Suppose that we have a light source and two receivers, and the source is placed exactly between the two receivers, as we see in the figure 12.
Light source and receivers are stationary relative to each other(figure 12).
At the beginning the light source does not emit anything, but at some point the light source will start to emit every second an electromagnetic signal/wave towards all directions.
This means that the source will not emit electromagnetic radiation(light) continuously, like the Sun or a light bulb does, but instead it will emit
electromagnetic radiation(light) every second for a very small duration of time, and in between the source does not emit anything.
You can call it electromagnetic wave or electromagnetic pulse or electromagnetic signal or light wave, but the important fact is that it is something that is not happening continuously, but instead it is radiation that is emitted every second by the source, and the rest of the time the source does not emit anything.
This way of creating the example will help us understand.
So, every time that the source emits radiation, a wave of light is created.
And here is the important part:
On our example the light source will not be at the hypothetical centre of the light waves!!!
On our example, as the electromagnetic wave is moving away from the source, the radiation that is moving towards the receiver 2 is at half the distance away from the source compared to the distance between the source and the radiation that is moving towards the receiver 1(as we see on the figure 13).
Our goal is to see in what rate(frequency) the two receivers will receive the light waves/signals that the source will emit!!!
The two receivers will receive the waves/signals in the same rate or not???
Let's start.
At some point, our light source emits the first electromagnetic radiation and the first light wave is created.
On the pictures each wave has a different color so that we can distinguish which is which.
The first wave is orange-colored.
When the first/orange wave reaches the receiver 1 the other part of the wave that is moving towards the receiver 2 is at half the distance between the light source and the receiver 2(figure 13).
Suppose that at this moment the light source emits the second electromagnetic wave.
The second wave is red-colored.
When the second/red wave reaches the receiver 1 the first/orange wave reaches the receiver 2(figure 14).
At this moment the source emits the third electromagnetic wave.
The third wave is blue-colored.
When the third/blue wave reaches the receiver 1 the second/red wave reaches the receiver 2(figure 15), and as the source continues to emit an electromagnetic wave every second, when the fourth wave reaches the receiver 1 the third wave reaches the receiver 2, and when the fifth wave reaches the receiver 1 the fourth wave reaches the receiver 2, and when the sixth wave reaches the receiver 1 the fifth wave reaches the receiver 2, and so on and so forth!!!
So, the waves reaching the two receivers at the same rate, meaning that there will not be "doppler effect" caused by the rate/frequency by which the waves reaching the two receivers, even though the source is not at the hypothetical centre of the expanding light waves!!!
(There will be redshift & blueshift for a different reason. Keep reading after the figure 15.)
The intervals between the waves that they receive will be the same for the two receivers, and in both receivers the interval between each wave will be one second, the same interval by which the waves are emitted by the source!!!
If the two receivers are on the move relative to the source(but stationary relative to each other) they will receive the light waves in a different rate/frequency!!!
But, if the two receivers are stationary relative to the source(like they are on this example), they will receive the light waves at the same rate
regardless if the source is at the centre of the waves or not!!!
If we have previously synchronised the clocks on the receivers and the source by sending an electromagnetic signal/wave from the source to the receivers, the two receivers will have the same time when they receive the first/orange wave because the synchronisation wave/signal will move in the same way with the rest of the electromagnetic waves that we will send later, meaning that the synchronisation signal/wave will reach the receiver 1 first, as also the first/orange wave will do!!!
On this example, the distance between the source and the wavefront that is moving towards the receiver 2 is 1/2 of the distance between the source and the wavefront that is moving towards the receiver 1(figure 13).
I did that because with this arrangement in the pictures we depict different waves to reach simultaneously the two receivers, as we see in the figures 14 & 15, and this is helping us to understand that the two receivers will receive the waves with the same interval between each wave(comparing the two receivers with each other), meaning that they will receive the waves at the same rate/frequency, even though the source is not at the centre of the waves.
If instead of 1/2, the distance between the source and the wavefront that is moving towards the receiver 2 is 1/3, or 1/4, or 1/5, or 1/6, or 1/7,
or 1/8, and so on, compared to the distance between the source and the wavefront that is moving towards the receiver 1, the final result will always be the same, meaning that the two receivers will always receive the waves with the same interval between each wave(the same interval while comparing the two receivers with each other), meaning that the two receivers will always receive the waves at the same rate/frequency(the same rate while comparing the two receivers with each other).
How it will happen, you will ask???
On the example presented here, where the distance between the source and the wavefront that is moving towards the receiver 2 is 1/2 of the distance between the source and the wavefront that is moving towards the receiver 1, when the first wave reaches the receiver 2 the second wave reaches the receiver 1(figure 14), and after that, when a wave reaches the one receiver another wave reaches the other receiver,
meaning that the two receivers will receive the waves at the same rate!!!
If the distance between the source and the wavefront that is moving towards the receiver 2 is 1/3 of the distance between the source and the wavefront that is moving towards the receiver 1, when the first wave reaches the receiver 2 the third wave will reach the receiver 1, and after that, when a wave reaches the one receiver another wave reaches the other receiver, meaning that the two receivers will receive the waves at the same rate!!!
If the distance between the source and the wavefront that is moving towards the receiver 2 is 1/4 of the distance between the source and the wavefront that is moving towards the receiver 1, when the first wave reaches the receiver 2 the fourth wave will reach the receiver 1, and after that, when a wave reaches the one receiver another wave reaches the other receiver, meaning that the two receivers will receive the waves at the same rate!!!
If the distance between the source and the wavefront that is moving towards the receiver 2 is 1/5 of the distance between the source and the wavefront that is moving towards the receiver 1, when the first wave reaches the receiver 2 the fifth wave will reach the receiver 1, and after that, when a wave reaches the one receiver another wave reaches the other receiver, meaning that the two receivers will receive the waves at the same rate!!!
It is easy to figure out how it continues!!!!!
With these ratios for the distances, 1/2, 1/3, 1/4, 1/5, 1/6, 1/7, and so on, in a picture we will depict different waves to reach simultaneously the two receivers, as we see in the figures 14 & 15, and this will help us to understand that the two receivers will receive the waves with the same interval between each wave, meaning that they will receive the waves at the same rate/frequency.
But, this will be the result regardless of how the light wave is moving in relation to the source, if the receivers are stationary relative to the source!!!
For example, if the distance between the source and the wavefront that is moving towards the receiver 2 is 95 percent of the distance between the source and the wavefront that is moving towards the receiver 1, in a picture we will not depict waves reaching simultaneously the two receivers, but again the two receivers will receive the waves with the same interval between each wave(comparing the two receivers with each other), meaning that the two receivers will receive the waves at the same rate/frequency(comparing the two receivers with each other).
There is a big error of the scientific community when they try to exlain the "doppler effect" in light, which is an error in the way that we think that the light is moving away from the source!!!
On our example the light source will not be at the hypothetical centre of the light waves!!!
On our example, as the electromagnetic wave is moving away from the source, the radiation that is moving towards the receiver 2 is at half the distance away from the source compared to the distance between the source and the radiation that is moving towards the receiver 1(as we see on the figure 13).
Our goal is to see in what rate(frequency) the two receivers will receive the light waves/signals that the source will emit!!!
The two receivers will receive the waves/signals in the same rate or not???
Let's start.
At some point, our light source emits the first electromagnetic radiation and the first light wave is created.
On the pictures each wave has a different color so that we can distinguish which is which.
The first wave is orange-colored.
When the first/orange wave reaches the receiver 1 the other part of the wave that is moving towards the receiver 2 is at half the distance between the light source and the receiver 2(figure 13).
Suppose that at this moment the light source emits the second electromagnetic wave.
The second wave is red-colored.
Figure 13. The first/orange wave reaches the receiver 1.
When the second/red wave reaches the receiver 1 the first/orange wave reaches the receiver 2(figure 14).
At this moment the source emits the third electromagnetic wave.
The third wave is blue-colored.
When the third/blue wave reaches the receiver 1 the second/red wave reaches the receiver 2(figure 15), and as the source continues to emit an electromagnetic wave every second, when the fourth wave reaches the receiver 1 the third wave reaches the receiver 2, and when the fifth wave reaches the receiver 1 the fourth wave reaches the receiver 2, and when the sixth wave reaches the receiver 1 the fifth wave reaches the receiver 2, and so on and so forth!!!
So, the waves reaching the two receivers at the same rate, meaning that there will not be "doppler effect" caused by the rate/frequency by which the waves reaching the two receivers, even though the source is not at the hypothetical centre of the expanding light waves!!!
(There will be redshift & blueshift for a different reason. Keep reading after the figure 15.)
The intervals between the waves that they receive will be the same for the two receivers, and in both receivers the interval between each wave will be one second, the same interval by which the waves are emitted by the source!!!
If the two receivers are on the move relative to the source(but stationary relative to each other) they will receive the light waves in a different rate/frequency!!!
But, if the two receivers are stationary relative to the source(like they are on this example), they will receive the light waves at the same rate
regardless if the source is at the centre of the waves or not!!!
If we have previously synchronised the clocks on the receivers and the source by sending an electromagnetic signal/wave from the source to the receivers, the two receivers will have the same time when they receive the first/orange wave because the synchronisation wave/signal will move in the same way with the rest of the electromagnetic waves that we will send later, meaning that the synchronisation signal/wave will reach the receiver 1 first, as also the first/orange wave will do!!!
Figure 14. When the second/red wave reaches the receiver 1 the first/orange wave reaches the receiver 2.
Figure 15. When the third/blue wave reaches the receiver 1 the second/red wave reaches the receiver 2.
On this example, the distance between the source and the wavefront that is moving towards the receiver 2 is 1/2 of the distance between the source and the wavefront that is moving towards the receiver 1(figure 13).
I did that because with this arrangement in the pictures we depict different waves to reach simultaneously the two receivers, as we see in the figures 14 & 15, and this is helping us to understand that the two receivers will receive the waves with the same interval between each wave(comparing the two receivers with each other), meaning that they will receive the waves at the same rate/frequency, even though the source is not at the centre of the waves.
If instead of 1/2, the distance between the source and the wavefront that is moving towards the receiver 2 is 1/3, or 1/4, or 1/5, or 1/6, or 1/7,
or 1/8, and so on, compared to the distance between the source and the wavefront that is moving towards the receiver 1, the final result will always be the same, meaning that the two receivers will always receive the waves with the same interval between each wave(the same interval while comparing the two receivers with each other), meaning that the two receivers will always receive the waves at the same rate/frequency(the same rate while comparing the two receivers with each other).
How it will happen, you will ask???
On the example presented here, where the distance between the source and the wavefront that is moving towards the receiver 2 is 1/2 of the distance between the source and the wavefront that is moving towards the receiver 1, when the first wave reaches the receiver 2 the second wave reaches the receiver 1(figure 14), and after that, when a wave reaches the one receiver another wave reaches the other receiver,
meaning that the two receivers will receive the waves at the same rate!!!
If the distance between the source and the wavefront that is moving towards the receiver 2 is 1/3 of the distance between the source and the wavefront that is moving towards the receiver 1, when the first wave reaches the receiver 2 the third wave will reach the receiver 1, and after that, when a wave reaches the one receiver another wave reaches the other receiver, meaning that the two receivers will receive the waves at the same rate!!!
If the distance between the source and the wavefront that is moving towards the receiver 2 is 1/4 of the distance between the source and the wavefront that is moving towards the receiver 1, when the first wave reaches the receiver 2 the fourth wave will reach the receiver 1, and after that, when a wave reaches the one receiver another wave reaches the other receiver, meaning that the two receivers will receive the waves at the same rate!!!
If the distance between the source and the wavefront that is moving towards the receiver 2 is 1/5 of the distance between the source and the wavefront that is moving towards the receiver 1, when the first wave reaches the receiver 2 the fifth wave will reach the receiver 1, and after that, when a wave reaches the one receiver another wave reaches the other receiver, meaning that the two receivers will receive the waves at the same rate!!!
It is easy to figure out how it continues!!!!!
With these ratios for the distances, 1/2, 1/3, 1/4, 1/5, 1/6, 1/7, and so on, in a picture we will depict different waves to reach simultaneously the two receivers, as we see in the figures 14 & 15, and this will help us to understand that the two receivers will receive the waves with the same interval between each wave, meaning that they will receive the waves at the same rate/frequency.
But, this will be the result regardless of how the light wave is moving in relation to the source, if the receivers are stationary relative to the source!!!
For example, if the distance between the source and the wavefront that is moving towards the receiver 2 is 95 percent of the distance between the source and the wavefront that is moving towards the receiver 1, in a picture we will not depict waves reaching simultaneously the two receivers, but again the two receivers will receive the waves with the same interval between each wave(comparing the two receivers with each other), meaning that the two receivers will receive the waves at the same rate/frequency(comparing the two receivers with each other).
A significant error of the scientific community.
It is an error which has to do with the position of the light source in relation to the expanding light waves!!!
When scientists want to depict a case where a light source and an observer(human, car, spaceship, etc.) are stationary relative to each other, they always place the light source at the hypothetical centre of the light waves that it has emit!!!
But this is totally wrong because whether or not an observer is on the move relative to a source is unrelated to whether or not the source is at the centre of the light waves that it has emit!!!
It is wrong to think that the source is always at the hypothetical centre of the light waves when there is no relative motion between us and the source!!!
It is wrong to think that the source is always at the hypothetical centre of the light waves when there is no relative motion between us and the source!!!
It is totally wrong to correlate the fact that there is no relative motion between the source and the observer with the probability of the source being at the centre of its own light waves!!!
Also, the scientists, when they wanted to depict a case where the observer is on the move but the source is not, they always placed the light source at the hypothetical centre of the light waves that it has emit!!!
They are depicting the light source not at the hypothetical centre of the waves only when they are depicting the source to be on the move and the observer is not!!!
If for example we have a light source and a human in relative motion with each other, when they depict the human on the move they have the source at the hypothetical centre of the light waves, but when they depict the source on the move they have the source not at the centre of the light waves!!!
But this is totally wrong!!!
Whether or not the light source is at the hypothetical centre of the light waves that it has emit is unrelated to whether or not there is relative motion between an observer and the source!!!
Whether or not the light source is at the hypothetical centre of its own light waves is something that must be evaluated independently from anything else!!!
As you can understand with the help of this example(figures 12, 13, 14, 15), we can have a light source not to be at the hypothetical centre of its own light waves, and we will receive the light waves at the same frequency/rate at which they are emitted by the source if we are stationary relative to the source!!!
An important explanation about the changes in the energy of photons, meaning about the "redshift" and the "blueshift".
On the last example(figures 14, 15) we have seen that the waves will reach the receivers 1 & 2 at the same rate/frequency even though the source is not at the hypothetical centre of the light waves!!!
But, something else happens!
When the photons of the waves will reach the two receivers(figures 14, 15), the interaction of the photons with the particles on the receivers will not be the same on the two receivers, meaning that the photoelectric effect, the Compton scattering, etc., will not be the same on the two receivers!!!
What does this mean???
The source has emit identical photons towards all directions(figures 14, 15), but the receiver 1 will detect higher energy photons and the
receiver 2 will detect lower energy photons!!!
The receiver 1 will detect photons with higher frequency & shorter wavelength(higher energy) and the receiver 2 will detect photons with lower frequency & larger wavelength(lower energy)!!!
So, the receiver 1 will detect blueshift on the photons and the receiver 2 will detect redshift(figures 14, 15)!!!
Why this will happen???
This will happen because the speed of the photons(speed relative to the source and the receivers) that are moving towards the receiver 1
is larger than the speed of the photons(speed relative to the source and the receivers) that are moving towards the receiver 2!!!
As the photons moving away from the source, they are not all the photons at the same distance away from the source(figure 13).
Some photons are closer to the source and some photons are farther away from the source.
This means that we must say that the relative speed between the source and the photons is not the same for all the photons, and this also applies to the receivers since they are stationary relative to the source!!!
We talk about the wave-particle duality and we say that all matter exhibit wave-like behavior.
The scientific community says that all particles, and not only photons, behave also as waves.
Also, the scientists, when they wanted to depict a case where the observer is on the move but the source is not, they always placed the light source at the hypothetical centre of the light waves that it has emit!!!
They are depicting the light source not at the hypothetical centre of the waves only when they are depicting the source to be on the move and the observer is not!!!
If for example we have a light source and a human in relative motion with each other, when they depict the human on the move they have the source at the hypothetical centre of the light waves, but when they depict the source on the move they have the source not at the centre of the light waves!!!
But this is totally wrong!!!
Whether or not the light source is at the hypothetical centre of the light waves that it has emit is unrelated to whether or not there is relative motion between an observer and the source!!!
Whether or not the light source is at the hypothetical centre of its own light waves is something that must be evaluated independently from anything else!!!
As you can understand with the help of this example(figures 12, 13, 14, 15), we can have a light source not to be at the hypothetical centre of its own light waves, and we will receive the light waves at the same frequency/rate at which they are emitted by the source if we are stationary relative to the source!!!
On the last example(figures 14, 15) we have seen that the waves will reach the receivers 1 & 2 at the same rate/frequency even though the source is not at the hypothetical centre of the light waves!!!
But, something else happens!
When the photons of the waves will reach the two receivers(figures 14, 15), the interaction of the photons with the particles on the receivers will not be the same on the two receivers, meaning that the photoelectric effect, the Compton scattering, etc., will not be the same on the two receivers!!!
What does this mean???
The source has emit identical photons towards all directions(figures 14, 15), but the receiver 1 will detect higher energy photons and the
receiver 2 will detect lower energy photons!!!
The receiver 1 will detect photons with higher frequency & shorter wavelength(higher energy) and the receiver 2 will detect photons with lower frequency & larger wavelength(lower energy)!!!
So, the receiver 1 will detect blueshift on the photons and the receiver 2 will detect redshift(figures 14, 15)!!!
Why this will happen???
This will happen because the speed of the photons(speed relative to the source and the receivers) that are moving towards the receiver 1
is larger than the speed of the photons(speed relative to the source and the receivers) that are moving towards the receiver 2!!!
As the photons moving away from the source, they are not all the photons at the same distance away from the source(figure 13).
Some photons are closer to the source and some photons are farther away from the source.
This means that we must say that the relative speed between the source and the photons is not the same for all the photons, and this also applies to the receivers since they are stationary relative to the source!!!
We talk about the wave-particle duality and we say that all matter exhibit wave-like behavior.
The scientific community says that all particles, and not only photons, behave also as waves.
According to the scientific community, any particle(proton, electron, etc.) has frequency and wavelength, like the photons.
The frequency & wavelength of a particle is related to the energy of the particle.
In addition to that, for all particles(photon, electron, proton, etc.) we can have changes in its energy, which for a photon we call it "blueshift" or "redshift".
In addition to that, for all particles(photon, electron, proton, etc.) we can have changes in its energy, which for a photon we call it "blueshift" or "redshift".
Higher energy of a particle means higher frequency and shorter wavelength, which we call it "blueshift"!!!
Lower energy of a particle means lower frequency and larger wavelength, which we call it "redshift"!!!
But, according to the scientific community, there is a difference regarding the changes on the energy of photons and the changes on the energy of other particles!!!
Regarding all the other particles(protons, electrons, etc.) but not the photons, the scientific community says that the energy of a particle changes when its speed relative to us changes, meaning that also the frequency and the wavelength of the particle changes!!!
With higher relative speed the particle has higher energy, meaning higher frequency and shorter wavelength.
Regarding all the other particles(protons, electrons, etc.) but not the photons, the scientific community says that the energy of a particle changes when its speed relative to us changes, meaning that also the frequency and the wavelength of the particle changes!!!
With higher relative speed the particle has higher energy, meaning higher frequency and shorter wavelength.
With lower relative speed the particle has lower energy, meaning lower frequency and larger wavelength.
But, according to the scientific community, the changes on the energy of a photon do not occur due to changes in relative speed, but they occur due to other reasons, because according to the scientific community the speed of light is always the same!!!!
My idea(regarding the changes in the energy of the photons).
Changes on the energy of photons occur due to changes in the relative speed between photons and observers(maybe they also occur due to other reasons)!!!
In my opinion, what happens with the other particles(protons, electrons, etc.) also happens with the photons, meaning that we detect blueshift and redshift on photons for the same reason that we detect changes in the energy on other particles, meaning that we detect changes in the energy of a photon when its speed relative to us changes, which is what happens with the other particles(protons, electrons, etc.)!!!
The scientific community believes that the one-way speed of the photons is always the same, and the redshift & blueshift on photons is not the result of different speed relative to us!!!
But this is wrong!!!
Let's say that we have a proton on the move in a particle accelerator.
When the proton collides with a detector, the higher the relative speed between the proton and the detector, the higher the energy that the detector will find, meaning that the detector will detect higher frequency & shorter wavelength on that proton as the speed increases!!!
The lower the speed of the proton relative to the detector, the lower the energy that we detect, meaning that we detect lower frequency & larger wavelength compared to what we will detect with higher speed of the proton!!!
This is the reason why we also detect changes in the energy of the photons!!!
If we have two identical photons moving towards two detectors but at different speeds relative to the detectors, when the photons collide with the detectors, on the case where between the photon and the detector the relative speed is lower the detector will find lower energy meaning lower frequency & larger wavelength(redshift), and on the case where between the photon and the detector the relative speed is higher the detector will find higher energy meaning higher frequency &
The scientific community believes that the one-way speed of the photons is always the same, and the redshift & blueshift on photons is not the result of different speed relative to us!!!
But this is wrong!!!
Let's say that we have a proton on the move in a particle accelerator.
When the proton collides with a detector, the higher the relative speed between the proton and the detector, the higher the energy that the detector will find, meaning that the detector will detect higher frequency & shorter wavelength on that proton as the speed increases!!!
The lower the speed of the proton relative to the detector, the lower the energy that we detect, meaning that we detect lower frequency & larger wavelength compared to what we will detect with higher speed of the proton!!!
This is the reason why we also detect changes in the energy of the photons!!!
If we have two identical photons moving towards two detectors but at different speeds relative to the detectors, when the photons collide with the detectors, on the case where between the photon and the detector the relative speed is lower the detector will find lower energy meaning lower frequency & larger wavelength(redshift), and on the case where between the photon and the detector the relative speed is higher the detector will find higher energy meaning higher frequency &
shorter wavelength(blueshift)!!!
The different relative speed between the photons and the detectors is not caused only by different motion of the photons!!!
The motion of the detectors can be the cause of the different relative speed!!!
All the photons will make the same motion compared to each other in a specific area in space!!!
In order to determine the relative speed between two objects, regardless if these objects are photons, protons, detectors, cars, planets, or anything else, we focus on the state of both objects, meaning that in order to determine the relative speed between a photon and a detector, we must focus not only on what the photons are doing but also on what the detectors are doing!!!
It is a collision between two objects that are in relative motion with each other, a collision between the detector and the particle(photon, electron, proton, etc.), and whether we consider that the particle is moving towards the detector or the detector towards the particle or both, it makes no difference!!!
This applies to all the particles, including the photons!!!
All the protons are the same, and the reason why we find different energy during the collision between a proton and a detector is because there is different relative speed between the proton and the detector!!!
Whether we consider that the proton is moving towards the detector or the detector towards the proton it makes no difference!!!
Exactly the same applies also for the photons!!!
Specific photons that are emitted from sources through the same transition of the electrons between different energy levels, are always the same, and the reason why we find different energy during the collision between these specific photons and a detector is because there is different relative speed between the photon and the detector!!!
Whether we consider that the photon is moving towards the detector or the detector towards the photon or both, it makes no difference because all that we have is a particle and a detector in relative motion with each other!!!
( The "doppler effect" that is produced due to the relative motion between a receiver/detector and a light source that emits repeating light waves is produced through a different mechanism/process.
On the example in the figures 14-15 there was no relative motion between the source and the receivers, and so there was no difference on the rate/frequency at which the waves reach the two receivers, meaning that there was no "doppler effect", even though the source was not at the hypothetical centre of the waves.
But, if there is relative motion between the light source and the receivers, then there will be "doppler effect" because the light waves will not reach the receivers at the same rate/frequency.)
A proton moving at high speed inside a particle accelerator will have higher energy during the collision with a detector compared to a proton that moves with lower speed, and that happens because the energy of the collision is higher due to the fact that the relative speed between the proton and the detector is higher!!!
If we have two protons that are moving with different speeds relative to a detector, the proton that moves with the lower speed will have lower energy during the collision with the detector, meaning that it will have lower frequency & larger wavelength compared to the other proton that moves with higher speed and it will have higher energy during the collision with the detector!!!
A proton moving at high speed inside a particle accelerator will have higher energy during the collision with a detector compared to a proton that moves with lower speed, and that happens because the energy of the collision is higher due to the fact that the relative speed between the proton and the detector is higher!!!
If we have two protons that are moving with different speeds relative to a detector, the proton that moves with the lower speed will have lower energy during the collision with the detector, meaning that it will have lower frequency & larger wavelength compared to the other proton that moves with higher speed and it will have higher energy during the collision with the detector!!!
The same happens with the photons, meaning that when the relative speed between a photon and a detector is higher, at the moment that the photon hits the detector it will have higher energy(blueshift) because the energy of the collision is higher due to the higher relative speed between the photon and the detector, and on that same photon or to an identical to that, when the relative speed between the photon and the detector is lower the detector will detect photon with lower energy,
meaning lower frequency & larger wavelength(redshift), due to the fact that the energy of the collision between the photon and the detector is lower!!!
Idea: It seems to me that particles(photons, electrons, protons, etc,) don't actually have wavelength & frequency, but it is just something that we have attributed to them without actually having it!!!!!
There is a chance that some may misunderstood what I'm saying, so, I will clarify.
Photons are emitted by electrons in atoms through specific transitions of the electrons between different energy levels!!!
The atoms of each element emit photons with specific energy that is different than the energy of photons that are emitted by the atoms of other elements.
For example, the atoms of hydrogen emit photons with different energy than the atoms of helium.
So, not all photons are the same regarding their energy at the moment of their emission by the atoms.
There are many different photons that are emitted/created by the atoms with different energies compared to each other!!!
Now, regarding the changes in the energy of photons, what i'm saying is this:
There are many different photons with different energies compared to each other, and they are emitted by the atoms with this different energy, but when photons collide with a detector we find different energy than the energy that we are expecting
depending on their speed relative to the detector!!!
For example:
Suppose we have atoms of a certain element, and these atoms emit photons that are moving towards some detectors.
We expect these photons to have a specific energy, but when they will collide with our detectors we will find that they have different energy.
The reason why we find different energy to these photons than the energy that we are expecting is the result of the different relative speed between the photons and our detectors!!!
Another idea(related to gravitational blueshift & redshift).
On the examples in the figures 1, 2, 3, 4, 5, 6, 7, 8 & 9 we have seen how the situation will look like if we are above the surface of a planet and we are looking down towards the surface and a source of light is in our line of sight in front of the planet.
Next we will see how the situation will look like(how we will depict the situation) if we are away from a planet(but not too far away from it), and we are looking towards the planet(Earth) and a light source is next to it, and in our line of sight behind the light source is the empty space and not the surface of the planet(figures 16-17).
According to the humans on the planet(Earth), this light source is some metres above the surface of the planet(at a higher altitude), but for us that we are away from the planet the source appears to be next to the planet(figures 16-17).
(In the pictures the Earth is small compared to the source and the detectors in order to fit in the pictures)
Suppose that we have a source of light located at some height above the surface of the Earth.
It can be 10 metres, or 100 metres, or 1000 metres above the surface, it doesn't really matter as long as it's not too far from the planet.
The light source is placed exactly between two detectors that can detect the photons that the source will emit(figures 16, 17).
The one detector is at lower altitude and the other detector is at higher altitude and the source is exactly between them(figures 16, 17).
Source and detectors are stationary relative to each other and are also stationary relative to the Earth.
At some point the light source emits photons towards all directions, meaning that a light wave will be created(figure 16).
( On the figure 16 we see a two-dimensional wave. The light source actually emits a three-dimensional wave, but we cannot depict that.
In order to visualise how the light wave that we see in the figure 16 will look like as a three-dimensional wave, you have to combine the figure 16 with the figures 2, 3B, 4, 6, 7)
At some point the light source emits photons towards all directions, meaning that a light wave will be created(figure 16).
( On the figure 16 we see a two-dimensional wave. The light source actually emits a three-dimensional wave, but we cannot depict that.
In order to visualise how the light wave that we see in the figure 16 will look like as a three-dimensional wave, you have to combine the figure 16 with the figures 2, 3B, 4, 6, 7)
The light source will not be at the hypothetical centre of the expanding light wave, as we see in the figure 16.
This will happen because the gravity of the Earth affects the motion of the photons and pulls them towards the planet(figure 16).
It's like if the gravity of the Earth pulls the whole light wave towards the planet, and as a result, the light source will not be at the centre of the light wave(figure 16).
When the photons will reach the two detectors(figures 16, 17), the interaction of the photons with the particles on the detectors will not be the same on the two detectors, meaning that the photoelectric effect, the Compton scattering, etc., will not be the same on the two detectors!!!
This will happen because the gravity of the Earth affects the motion of the photons and pulls them towards the planet(figure 16).
It's like if the gravity of the Earth pulls the whole light wave towards the planet, and as a result, the light source will not be at the centre of the light wave(figure 16).
When the photons will reach the two detectors(figures 16, 17), the interaction of the photons with the particles on the detectors will not be the same on the two detectors, meaning that the photoelectric effect, the Compton scattering, etc., will not be the same on the two detectors!!!
On the figure 17 we see only two of the photons that are moving towards the detectors, instead of seeing the whole light wave.
The light source emits a light wave towards all directions meaning that it emits many photons towards all directions, but on the figure 17 we see only two of these photons, and we see that the photon moving towards the Earth is farther away from the source, and the photon that is moving away from the Earth is closer to the light source.
The two detectors will not detect the same energy on the photons even though the light source has emit identical photons towards all directions(figures 16, 17)!!!
The detector 1 will detect photons with higher energy(blueshift), meaning photons with higher frequency & shorter wavelength, and the detector 2 will detect photons with lower energy(redshift), meaning photons with lower frequency & larger wavelength!!!
The two detectors will not detect the same energy on the photons even though the light source has emit identical photons towards all directions(figures 16, 17)!!!
The detector 1 will detect photons with higher energy(blueshift), meaning photons with higher frequency & shorter wavelength, and the detector 2 will detect photons with lower energy(redshift), meaning photons with lower frequency & larger wavelength!!!
Why the detectors will not detect the same energy on the photons, even though the light source has emit identical photons towards all directions???
Let's see why.
The photons that are emitted by the light source are pulled by the gravity of the planet, and that's why the light source is not at the hypothetical centre of the light wave(figure16)!!!
The photons that are emitted by the light source are pulled by the gravity of the planet, and that's why the light source is not at the hypothetical centre of the light wave(figure16)!!!
The reason why the detector 1 will detect photons with higher energy is obvious from what the figure 16 shows.
The photons that are moving towards the Earth and the detector 1 will move faster because they are pulled by the gravity of the planet and that's why are farther away from the light source(figures 16, 17), and the photons that are moving away from the Earth and towards the detector 2 will move slower because their motion is restrained by the gravity of the planet and that's why are closer to the source.
So, the photons are not having the same speed relative to the source and also relative to the detectors!!!
If we compare the energy of the collision between the detector 1 and the photons with the energy of the collision between the detector 2 and the photons, we will find that the collision between the photons and the detector 1 has higher energy(figure 17), meaning that we will say that the photons are having higher energy, but it is not the energy of the photons that it is higher, it's the energy of the collision between the detector and the photons that is higher!!!!!
The detector 1 will detect photons with higher energy(higher frequency & shorter wavelength) because the energy of the collision between the detector 1 and the photons will be larger due to the higher relative speed between the photons and the detector 1(figure 17).
The detector 2 will detect photons with lower energy(lower frequency & larger wavelength) because the energy of the collision between the detector 2 and the photons will be lower due to the slower relative speed between the photons and the detector 2(figure 17).
And another idea(related to blueshift & redshift).
At the beginning of this paper, on the examples in the figures 1, 2 & 3, we have seen that a light source which is stationary on the surface of the Earth will not be at the hypothetical centre of the light waves that it will emit.
Now let's see something else about a source that is stationary on the surface of the Earth, that is related to what I have said in the examples in the figures 13, 14, 15, 16 & 17 about the redshift and the blueshift.
Suppose that we have a source of light placed on the Equator, and it is stationary relative to the surface of the Earth(figure 18).
The light source is placed exactly between two detectors that can detect the photons that the source will emit(figure 18).
The two detectors are also placed on the Equator, and the one detector(detector 1) is placed towards the direction of the West relative to the light source, and the other detector(detector 2) is placed towards the direction of the East relative to the source(figure 18).
Light source and detectors are stationary relative to each other.
The detector 1 will detect photons with higher energy(higher frequency & shorter wavelength) because the energy of the collision between the detector 1 and the photons will be larger due to the higher relative speed between the photons and the detector 1(figure 17).
The detector 2 will detect photons with lower energy(lower frequency & larger wavelength) because the energy of the collision between the detector 2 and the photons will be lower due to the slower relative speed between the photons and the detector 2(figure 17).
Figure 16. The light source will not be at the hypothetical centre of the light wave.
The light source will emit identical photons towards all directions but the two detectors will not detect the same photons.
The detector 1 will detect photons with higher energy(blueshift) and the detector 2 will detect photons with lower energy(redshift).
Figure 17. The detector 1 will detect photons with higher energy(higher frequency) and
the detector 2 will detect photons with lower energy(lower frequency).
And another idea(related to blueshift & redshift).
At the beginning of this paper, on the examples in the figures 1, 2 & 3, we have seen that a light source which is stationary on the surface of the Earth will not be at the hypothetical centre of the light waves that it will emit.
Now let's see something else about a source that is stationary on the surface of the Earth, that is related to what I have said in the examples in the figures 13, 14, 15, 16 & 17 about the redshift and the blueshift.
Suppose that we have a source of light placed on the Equator, and it is stationary relative to the surface of the Earth(figure 18).
The light source is placed exactly between two detectors that can detect the photons that the source will emit(figure 18).
The two detectors are also placed on the Equator, and the one detector(detector 1) is placed towards the direction of the West relative to the light source, and the other detector(detector 2) is placed towards the direction of the East relative to the source(figure 18).
Light source and detectors are stationary relative to each other.
Light source and detectors are moving towards the East due to the rotation of the Earth(figure 18).
At some point the light source emits photons towards all directions, meaning that a light wave will be created(figure 18).
The light source will not be at the hypothetical centre of the light wave due to the rotation of the Earth, as we see in the figure 18, and as I have explain in the figures 1, 2 & 3 at the beginning of this paper.
(The light source that we see in the figure 18 it's in the same situation with the light bulb A in the figures 1, 2 & 3)
When the photons will reach the two detectors(figure 18), the interaction of the photons with the particles on the detectors will not be the same on the two detectors, meaning that the photoelectric effect, the Compton scattering, etc., will not be the same on the two detectors!!!
At some point the light source emits photons towards all directions, meaning that a light wave will be created(figure 18).
The light source will not be at the hypothetical centre of the light wave due to the rotation of the Earth, as we see in the figure 18, and as I have explain in the figures 1, 2 & 3 at the beginning of this paper.
(The light source that we see in the figure 18 it's in the same situation with the light bulb A in the figures 1, 2 & 3)
When the photons will reach the two detectors(figure 18), the interaction of the photons with the particles on the detectors will not be the same on the two detectors, meaning that the photoelectric effect, the Compton scattering, etc., will not be the same on the two detectors!!!
On the previous example I have used two pictures(figures 16 & 17), and in the figure 16 we see a light wave and in the figure 17 we see only two of the photons that consist the light wave, but on this example I use only one picture(the figure 18), and on the figure 18 we see both the light wave and two of the photons that consist the light wave, and these two photons will collide with the detectors.
The two detectors will not detect the same energy on the photons even though the source has emit identical photons towards all directions(figure 18)!!!
The detector 1 will detect photons with higher energy(blueshift), meaning photons with higher frequency & shorter wavelength, and the detector 2 will detect photons with lower energy(redshift), meaning photons with lower frequency & larger wavelength!!!
Why the detectors will not detect the same energy on the photons, even though the light source has emit identical photons towards all directions???
The detector 1 will detect photons with higher energy(blueshift), meaning photons with higher frequency & shorter wavelength, and the detector 2 will detect photons with lower energy(redshift), meaning photons with lower frequency & larger wavelength!!!
Why the detectors will not detect the same energy on the photons, even though the light source has emit identical photons towards all directions???
Let's see why.
Due to the rotation of the Earth the light source and the detectors are moving towards the East, meaning that the source will not be at the hypothetical centre of its own light wave(figure 18)!!!
The detector 1 will collide with the photons that the source has emit towards the West, and the detector 2 will collide with the photons that the source has emit towards the East.
If we compare the energy of the collision between the detector 1 and the photons with the energy of the collision between the detector 2
Due to the rotation of the Earth the light source and the detectors are moving towards the East, meaning that the source will not be at the hypothetical centre of its own light wave(figure 18)!!!
The detector 1 will collide with the photons that the source has emit towards the West, and the detector 2 will collide with the photons that the source has emit towards the East.
If we compare the energy of the collision between the detector 1 and the photons with the energy of the collision between the detector 2
and the photons, we will find that the collision between the photons and the detector 1 has higher energy(figure 18), meaning that we will say that the photons are having higher energy!!!!!
Due to the rotation of the Earth the detector 1 is moving towards the East, but the photons with which will collide are moving towards the West!!
So, the photons that are emitted towards the West are moving towards the detector 1, and the detector 1 is moving towards the photons because it is moving towards the East due to the rotation of the Earth(figure 18), and due to that, the energy of the collision between the photons and the detector 1 will be higher!!!
Due to the rotation of the Earth the detector 1 is moving towards the East, but the photons with which will collide are moving towards the West!!
So, the photons that are emitted towards the West are moving towards the detector 1, and the detector 1 is moving towards the photons because it is moving towards the East due to the rotation of the Earth(figure 18), and due to that, the energy of the collision between the photons and the detector 1 will be higher!!!
The photons that are emitted towards the East are moving towards the detector 2, and the detector 2 is also moving towards the East due to the rotation of the Earth(figure 18), and it's like if the detector 2 is trying to move away from the photons, and due to that, the energy of the collision between the photons and the detector 2 will be lower!!!
SO, IT IS NOT THE ENERGY OF THE PHOTONS THAT IT IS DIFFERENT, BUT IT'S THE ENERGY OF THE COLLISION BETWEEN THE DETECTORS AND THE PHOTONS THAT IS DIFFERENT!!!
As we see in the figure 18, the detector 1 is closer to the expanding light wave than the detector 2 because the detector 1 is moving towards the light wave and the detector 2 is moving away from the light wave, and this is happening because the detectors are moving towards the East due to the rotation of the Earth!!!
As we see in the figure 18, the detector 1 is closer to the expanding light wave than the detector 2 because the detector 1 is moving towards the light wave and the detector 2 is moving away from the light wave, and this is happening because the detectors are moving towards the East due to the rotation of the Earth!!!
Τhe detector 1 will detect photons with higher energy(higher frequency & shorter wavelength) due to the higher relative speed between the photons and the detector 1, and the detector 2 will detect photons with lower energy(lower frequency & larger wavelength) due to the lower relative speed between the photons and the detector 2(figure 18).
Figure 18. The light source and the detectors are moving towards the East due to the rotation of the Earth.
The source will emit identical photons towards all directions but the two detectors will not detect the same photons.
The detector 1 will detect photons with higher energy(blueshift) and the detector 2 will detect photons with lower energy(redshift).
To help you realise what I'm saying I will use two examples, the one using cars and the other using protons.
First example:
Suppose we have two cars on the surface of the Earth.
The car A and the car B.
The two cars will collide with each other, and I will use two different scenarios of collision.
The car A will have a damage from the collision, and we will use this damage to determine the energy of the collision between the two cars,
meaning that the car A has the role of a detector of energy on the example, like the detectors that we see on the examples in the figures 16,
17 & 18.
The bigger the damage on the car A, the bigger the energy of the collision!!!
First scenario: If the car A is stationary relative to the surface of the Earth and the car B is moving towards the car A at a specific speed, there will be a damage to the car A when the two cars collide.
Second scenario: While the car B is on the move, if also the car A is moving towards the car B, the damage on the car A will be bigger!!!
The car A has the role of a detector of energy on the example.
On the second scenario, the damage on the car A will be bigger(compared to the first scenario) not because the energy of the car B is higher, but because the energy of the collision between the two cars is higher!!!
Similarly on the example in the figure 18, the detector 1 will have bigger "damage" from the collision with the photons compared to the "damage" that the detector 2 will have, not because the photons will have higher energy, but because the energy of the collision will be higher, meaning that the photoelectric effect, the Compton scattering, etc., will not be the same on the two detectors due to different energy of the collision between photons and detectors, and not due to different energy of the photons!!!
So, the bigger "damage" that the detector 1 will have is not the result of higher energy of the photons, but it will occur because the energy of the collision between the detector 1 and the photons will be higher, meaning that this bigger "damage" on the detector will be interpreted as the result of higher energy!!!
Second example:
In particle accelerators we have various particles that collide with detectors.
Suppose that we have a proton colliding with a detector.
The detector is stationary relative to the ground and relative to us, and the proton is moving towards the detector.
The higher the speed of the proton, the higher the energy that the detector will detect on the proton.
But, it is not the energy of the proton that is higher!!!
Instead, it is the energy of the collision between the proton and the detector that is higher!!!
To help you understand, imagine that a proton is stationary relative to us and a detector is moving towards the proton with high speed!!!
When the detector will collide with the proton, again the detector will detect higher energy on the proton, but it is the energy of the collision between the proton and the detector that will be higher, and not the energy of the proton!!!
The detector will have a damage caused by the collision with the proton, regardless if we consider that the particle is moving towards the detector or the detector towards the particle!!!
The different damage that the detector will have is the result of the collision and not the result of the different energy of the proton!!!
Similar situations occur with photons!!!
We use various detectors in various situations, and various particles collide with them, and when I say particles I include also the photons!!!
During the collision between a particle(proton, electron, photon, etc.) and a detector, some changes will occur to the detector from the impact with the particle, and the scientific community uses these changes on the detector to determine the energy of the particle(proton, electron, photon, etc.).
But, when the scientific community thinks that the energy of a particle has changed and that's why it gives us different results on the detector during the collision, it's not actually the energy of the particle that has changed!!!
Instead, it is the energy of the collision that changes due to different relative speed between the detector and the particle(proton, electron, photon, etc.)!!!
It is a collision between two objects that are in relative motion with each other, a collision between the detector and the particle(proton, electron, photon, etc.), and whether we consider that the particle is moving towards the detector or the detector towards the particle or both, it makes no difference!!!
This applies to all the particles, including the photons!!!
All the protons are the same, and the reason why we find different energy during the collision between a proton and a detector is because there is different relative speed between the proton and the detector!!!
Whether we consider that the proton is moving towards the detector or the detector towards the proton it makes no difference!!!
Exactly the same applies also for the photons!!!
Specific photons that are emitted from sources through the same transition of the electrons between different energy levels, are always the same, and the reason why we find different energy during the collision between these specific photons and a detector is because there is different relative speed between the photon and the detector!!!
Whether we consider that the photon is moving towards the detector or the detector towards the photon it makes no difference!!!
Whether we consider that the particle is moving towards the detector or the detector towards the particle or both, it makes no difference because all that we have is a particle and a detector in relative motion with each other!!!
An Explanatory example(regarding the changes in the energy of photons).
At the beginning of this paper(in the example with the figures A, B & C) we have seen that the light/photons always move in the same way regardless of the motion of the source.
In the example at the beginning(in the figures B - C) I have used waves of light, but next I will present a new example with the use of photons while describing the same thing.
The example at the beginning(figures B - C) was describing a situation on Earth, but the next example describes a situation away fom a planet.
Suppose that, away from a planet, we have two light sources that are moving towards each other(figure 19).
These are the light sources A & B(figure 19).
Both light sources are in a inertial reference frame.
The arrows that I use showing the motion of the light sources A & B(figure 19) are used only to indicate that the sources are in relative motion with each other, but each light source is in an inertial reference frame meaning that each light source considers itself as stationary!!!
The two light sources currently do not emit light(figure 19).
Figure 19. The two light sources are moving towards each other.
At some point the two light sources are next to each other(figure 20).
When the light sources are next to each other(figure 20), both light sources will emit a photon towards the direction that the light source A is suppose to be moving(figure 21).
Figure 20. When the two light sources are next to each other they will emit a photon.
The light source A will emit the photon A and the light source B will emit the photon B(figure 21).
The two photons that are emitted by the two sources will move exactly the same, and practically will remain next to each other(figure 21) while they are moving away from the sources, since they are emitted when the light sources were next to each other.
The light sources are moving away from each other because they are in relative motion(figure 21).
Figure 21. The two photons will make identical motion and we can say that practically
the two photons will be next to each other while they are moving away from the sources,
but the sources are moving away from each other.
What we see in the figures 19-20-21 is similar with what we have seen in the figures B,a - B - C at the beginning of this parer, and the difference is that on the one case we have light waves and on the other case we have photons.
At the beginning of this paper we have seen the example with the figures D,a - D - E - F, where the two light sources emit photons towards all directions, or in other words they emit a light wave towards all directions.
Next we will see an example that is similar to that.
For the next example we will use the figures 19 & 20 which present a situation that is identical with the situation on the figures D,a & D.
So, suppose that we have again the situation that is described in the figure 19 and there are two light sources that are moving towards each other, which is also what we see in the figure D,a.
When the two light sources are next to each other, as we see in the figure 20, both light sources will emit photons/light towards all directions and two light waves will be created(figure 22).
The light sources A & B are in relative motion with each other, so, after the emission of light they are moving away from each other(figure 22).
As we have seen at the beginning of this paper(figures D,a - D - E - F) there are two possibilities.
The one case is when both light sources are not at the hypothetical centre of the light wave the they have emit, which is what the figure F
presents, and the other case is what we see in the figure E where the one light source is located at the hypothetical centre of its own light wave.
We will use the case that we see in the figure E, and so, on the figure 22 we see that the two light sources have emit light/photons towards all directions, and the one light source is located at the hypothetical centre of its own light wave but the other light source is not.
Figure 22. When the two light sources were next to each other(figure 20) they emitted light/photons towards all directions and two waves of light are created.
The two light sources that we see in the figure 22 have emit photons towards all directions, and I present it in the picture as light waves moving away ftom the sources.
The light sources A & B have emitted the light when they were next to each other(figure 20).
Now, let's do the following.
Let's draw on the picture, on the figure 22, two of the photons that each source has emit and consist the light wave that the source has produce.
We draw, for each light source, one photon towards the direction from where the other source is coming, and another photon towards the direction that the other source is going(figure 23).
And so, we end up with the figure 23.
So, we draw on the picture, four photons towards two opposite directions(figure 23), two towards each direction, and each light source has emit two of these photons, one towards each direction.
Figure 23. The photons A1 & A2 are part of the light wave that the light source A has emit,
and the photons B1 & B2 are part of the light wave that the light source B has emit.
The light source A has emit the photons A1 & A2 and the light source B has emit the photons B1 & B2(figure 23).
The photons A1 & A2 are part of the light wave that the light source A has emit, and the photons B1 & B2 are part of the light wave that the light source B has emit(figure 23).
The light source in the figure 18 is in a similar situation with the light source A in the figure 23 and the green light source in the figure E, regarding the position of the source in relation to the light wave the it has emit.
Now let's do the following.
Let's remove from the figure 23 the two light waves that the sources have emit, and leave only the four photons(photons A1-A2-B1-B2)!!!
So, we end up with the figure 24.
Figure 24. We have removed the waves of light from the figure 23 and we end up with the figure 24 were we see only the four photons.
On the figure 24 we see only the four photons that are moving away from the light sources towards two opposite directions, and we have removed the waves of light that we see in the figure 23!
The photons A1 & B1 will move exactly the same and also the photons A2 & B2 will move exactly the same, and it's like if there are two pairs of photons that are moving away from the sources towards two opposite directions(figure 24).
As we see in the figure 24, the light source B is exactly between the two pairs of photons that are moving away from the light sources, but the light source A is not exactly between the two pairs of photons that are moving away from the sources!!!
The distance between the light source B and the photon B1 is the same with the distance between the light source B and the photon B2, but the distance between the light source A and the photon A1 is not the same with the distance between the light source A and the
photon A2.
On my paper " The anisotropy of the speed of light" you can find more examples that look like the figure 24, where sources emit photons and protons.
On the figure 24 we see similarities with the figure 21 and the figure C.
The figures 22-23-24 are helping us to understand what the figures 16 & 17 are showing.
The light source A on the figures 22-23-24 is in the same situation with the light source on the figures 16 &17, regarding the position of the source in relation to the photons/light.
Next, we will use the same examples that we have seen in the figures 19, 20, 22, 23 & 24, but we will add something new to the examples.
So, we have again the same scenario that we see in the figure 19, meaning that we have two light sources that are moving towards each other, but now, the light sources are not alone, as we see in the figure 25!
Each light source is located exactly between two detectors that can detect the photons that the source will emit(figure 25).
The light source A is placed exactly between the detectors A1 & A2(figure 25), and the light source B is placed exactly between the
detectors B1 & B2.
The detectors A1 & A2 are stationary relative to the light source A(figure 25), and the detectors B1 & B2 are stationary relative to the
light source B.
The two light sources are in relative motion with each other, and the detectors are located towards the two opposite directions towards which the sources are suppose to be moving.
So, relative to each light source, the two detectors that are stationary relative to the light source are placed as follows:
The one detector is located towards the direction from where the other source is coming, and the other detector is located towards the direction that the other source is going(figure 25).
Both light sources are in a inertial reference frame.
The arrows that I use showing the motion of the light sources and the detectors in the figure 25 and on the other figures, are used only to indicate that light sources and detectors are in relative motion with each other, but each light source and each detector is in an inertial reference frame meaning that they consider themselves as stationary!!!
The two light sources currently do not emit light(figure 25).
Figure 25. The light sources are moving towards each other, together with the detectors.
So, the two light sources are moving towards each other, together with the detectors(figure 25).
When the two light sources are next to each other, as we see in the figure 26, both light sources will emit photons/light towards all directions.
Figure 26. When the two light sources are next to each other, they will emit light/photons towards all directions.
On the figure 27 we see that the two light sources have emit light/photons towards all directions and we see the light waves that are created, but we also see four of the photons that consist the two light waves, as we have seen in the figure 23.
The light source A has emit the photons A1 & A2 and the light source B has emit the photons B1 & B2(figure 27).
The photons A1 & A2 are part of the light wave that the light source A has emit, and the photons B1 & B2 are part of the light wave that the light source B has emit(figure 27).
The photon A1 is moving towards the detector A1 and will collide with it(figures 27 & 28), and the photon A2 is moving towards the detector A2 and will collide with it.
The photon B1 is moving towards the detector B1 and will collide with it(figures 27 & 28), and the photon B2 is moving towards the detector B2 and will collide with it.
The figure 27 presents the case where the one source is located at the hypothetical centre of its own light wave, which is also what we see on the figure E and on the figure 23.
And something extremely important:
The light source A and the light source B are identical, meaning that the photons that they will emit are identical!!!
For example, the light sources can be identical gas-discharge lamps!!!
Therefore, the two light sources emit identical photons through the same transition of the electrons between different energy levels!!!
So, each light source will emit identical photons towards all directions, and since the light sources A & B are identical, also the photons that these two sources will emit will be identical with each other(figure 27).
Figure 27. The photons A1 & A2 are part of the light wave that the light source A has emit, and
the photons B1 & B2 are part of the light wave that the light source B has emit.
Now let's do the following.
Let's remove from the figure 27 the two light waves that the sources have emit, and leave only the four photons(photons A1-A2-B1-B2)!!!
And so, we end up with the figure 28.
The light source in the figure 18 is in a similar situation with the light source A on the figure 27 regarding the position of the source relative to the light/photons that it has emit.
The figures 27 & 28 are helping us to understand what the figures 16 & 17 are showing.
The light source A on the figures 27 & 28 is in a similar situation with the light source on the figures 16 & 17 regarding the position of the source relative to the light/photons that it has emit.
Figure 28. The light source A has emit the photons A1 & A2 and the light source B has emit the photons B1 & B2(figure 28).
The photon A1 will collide with the detector A1, the photon A2 will collide with the detector A2,
the photon B1 will collide with the detector B1, and the photon B2 will collide with the detector B2,
On the figure 28 we see only the four photons that are moving away from the light sources towards two opposite directions, and we have removed the waves of light that we see in the figure 27!
The light source A has emit the photons A1 & A2 and the light source B has emit the photons B1 & B2(figure 28).
As we see on the figure 28, the photons B1 & B2 are at the same distance from the light source B, but the the photons A1 & A2 are not at the same distance away from the light source A!!!
The photon A1 is closer to the light source A and the photon A2 is farther away from the light source A as the photons are moving away from the source, meaning that the relative speed between the photons and the light source is not the same for the two photons!!!
Also, the distance between the photon B1 and the detector B1 is the same with the distance between the photon B2 and the detector B2, but the distance between the photon A1 and the detector A1 is not the same with the distance between the photon A2 and the detector A2!
Now, I have to remind you something very important:
The detectors A1 & A2 are stationary relative to the light source A, and the detectors B1 & B2 are stationary relative to the light source B.
What energy the detectors will detect on the photons(figure 28)???
The light source B has emit identical photons towards all directions(figure 27), and the detectors B1 & B2 will detect the same energy on the photons B1 & B2(figure 28) when photons and detectors collide.
But, it will not happen the same for the detectors A1 & A2 that will detect the photons A1 & A2!!!
The light source A has emit identical photons towards all directions(figure 27), but when the photons A1 & A2 will collide with the detectors A1 & A2(figure 28), the interaction of the photons with the particles on the detectors will not be the same on the two detectors, meaning that the photoelectric effect, the Compton scattering, etc., will not be the same on the two detectors!!!
The detectors A1 & A2 will not detect the same energy on the photons A1 & A2 even though the light source has emit identical photons towards all directions(figures 27, 28)!!!
The detector A2 will detect that the photon A2 has higher energy(blueshift), meaning higher frequency & shorter wavelength(figure 28), and the detector A1 will detect that the photon A1 has lower energy(redshift), meaning lower frequency & larger wavelength!!!
The detector A2 will detect that the photon A2 has higher energy(blueshift), meaning higher frequency & shorter wavelength(figure 28), and the detector A1 will detect that the photon A1 has lower energy(redshift), meaning lower frequency & larger wavelength!!!
The light source A is identical with the light source B meaning that the photons that the two sources will emit will be identical, but the interaction of the photons A1-A2-B1-B2 with the particles on the detectors A1-A2-B1-B2 will not be the same on all detectors, meaning that the photoelectric effect, the Compton scattering, etc., will not be the same on all detectors, meaning that the four detectors will not detect the same energy on the photons emitted from the two sources.
The photon B1 is identical to the photon A1, but when the photon A1 will collide with the detector A1, the detector A1 will find that the photon A1 has lower energy than the energy that the detector B1 will find on the photon B1(figures 27, 28)!!!
The photon B2 is identical to the photon A2, but when the photon A2 will collide with the detector A2, the detector A2 will find that the photon A2 has higher energy than the energy that the detector B2 will find on the photon B2(figures 27, 28)!!!
So, the photons on our example are identical and are making the exact same motion, but the detectors will detect different energy during the collision between the photons and the detectors!!!
What happens is not that the energy of the photons is different!!!
All the photons on our example are identical!!!
What happens is that the energy of the collision between the detectors and the photons is different!!!
Question: Why is the energy of the collision different???
Answer: The energy of the collision is different due to the different relative speed between photons and detectors!!!
The arrows that I use in the pictures showing that light sources and detectors are moving are used only in order to show that there is relative motion between sources & detectors!!!
The reality is that each light source and each detector is in an inertial reference frame meaning that they consider themselves as stationary!!!
We can remove the arrows that are showing motion for the light sources and the detectors in the figures 27 & 28.
Next, we see the figures 29 & 30 where to each picture we see only the one of the sources and the detectors that are stationary relative to the source, and I use arrows only to show the motion of the photons because each light source and each detector is in an inertial reference frame, meaning that they consider themselves as stationary!!!
On the figure 29 we see only the light source B and on the figure 30 we see only the light source A.
If we combine the figures 29 & 30 we create the figure 28.
Figure 29. The two photons are always at the same distance from the source and at the same distance from the detectors.
The figure 30 is helping us to realise that the light source A considers itself as stationary because it is in an inertial reference frame, but the photons A1 & A2 are not having the same speed relative to the light source A because they are always not at the same distance from the source as they are moving away from it, and since the detectors A1 & A2 are stationary relative to the light source A, the photons A1 & A2 are also not having the same speed relative to the detectors A1 & A2 and that's why the detectors will not detect the same energy during the collision between photons and detectors!!!
Figure 30. The photons A1 & A2 are always not at the same distance from the light source as they are moving away from it.
The figure 30 is helping us to understand what the figure 17 is showing.
The light source A on the figure 30 is in a similar situation with the light source on the figure 17.
What we see in the last pictures is helping us to understand what it would have happened if we were using detectors on the examples in the figures 3,A - 3,B - 3,C - 3,D.
You can see more examples where sources emit photons & protons on my paper " The anisotropy of the speed of light".