The theory of relativity has become not credible?

[Bart]

On thelink: http://dl.dropbox.com/u/26262175/InterpreatationMichelsonExperiment.pdf

 

is presented the analysis of the Michelson-Morley experiment, which shows that this experiment could be misinterpreted.

 

Thus, whether the SR theory was based on false premises?

 

Has anyone checked this already?

 

Edited January 23, 2012 by Bart

[D H]

On the link: http://dl.dropbox.com/u/26262175/InterpreatationMichelsonExperiment.pdf is presented the analysis of the Michelson-Morley experiment, which shows that this experiment could be misinterpreted.

 

[Thus, whether the SR theory was based on false premises?

The only false premises here are those made in that crackpot article. From the article,

 

If the speed of light in air, shown by the Michelson-Morley experiment and in later experiments, is indeed constant in every direction and not depend on motion of the Earth, it is also legitimate to say that the speed of light measured in stationary water (~230 000 km/s), or glass (~170 000 km/s), also must be constant in each direction and independent of the speed of light source. If that were not true, it would have discovered long time ago, and then would be possible to construct universal speedmeters, based only on changes of the light speed, which is unreal.

 

On the other hand, if as shown, the speed of light is independent of the direction and of the movement of the light source, for each medium, then the light-clock uses eg. glass, in a rocket moving with any speed, will always indicate the same time as on Earth. Thus arguments of the special theory of relativity, about for example time dilation, are wrong.

 

It can be assumed then that the special theory of relativity, proposed by Albert Einstein in 1905, is based on false premises.

 

This is utter nonsense. The premise of special relativity theory is that the speed of light in vacuum is the same to all observers. Special relativity says nothing about the speed of light through matter. Getting a complete picture of how light interacts with matter took another than 40 years after Einstein's 1905 paper. You might want to study quantum electrodynamics, not some crackpot nonsense on the internet.

[swansont]

Well, there some obvious problems

 

"Impact of changes in pressure, temperature and humidity of the air on the speed of light, which is significant, is ignored here."

 

 

Is baloney. You only care if the values change during the experiment itself, since the results do not depend on the value of c. An interferometer that is ~1m long will have a round trip time of order 10 ns. Pressure, temperature and humidity rely on molecular interactions, with the molecules moving at perhaps a thousand km/s, or a micron per nanosecond. The same molecules will be in the beam on the outbound and return trip of the light, and the pressure, temperature and humidity will not have changed.

 

If there is a gradient in any of these values, you will measure it when you change the orientation of the interferometer. The gradient would have to always somehow mask the effect of the aether to be of significance, which is unthinkably unlikely.

 

The interferometers were not being asked to perform beyond their resolution. The rotation effect is of little consequence because stellar aberration shows we are not at rest with any purported aether. We have to be moving through it.

 

M-M was not an experiment to measure c. The basis for a constant c comes from Maxwell's equations. EM waves can't work unless c is the same in all frames.

[ajb]

There has been many direct and indirect tests of special and general relativity. To date there has been no experiment or observation to suggest that Einsteinian relativity is not a good theory.

[IM Egdall]

Bart, in your link the author is saying the Michelson Morley (MM) experiments did not show that the speed of light is absolute. The paper is correct.

 

Einstein's light postulate of special relativity says:

 

Light travels at the same speed with respect to all uniformly moving reference frames.

 

OR light travels at the same speed no matter what the speed of the source of that light.

 

But the MM experiments were done in a single reference frame. The light source, the test apparatus, and the detector (film I think) were all at rest with respect to each other (and the Earth.) So MM says nothing one way or another about whether the speed of light is absolute.

 

However, a number of other tests have shown the speed of light is absolute. DeSitter's famous binary star analysis in 1913 was the first one. In 1977, MIT physicist Ken Brecher used a similar technique to verify Einstein's light postulate to one part in a billion.

Edited January 23, 2012 by IM Egdall

[DrRocket]

This is utter nonsense. The premise of special relativity theory is that the speed of light in vacuum is the same to all observers. Special relativity says nothing about the speed of light through matter. Getting a complete picture of how light interacts with matter took another than 40 years after Einstein's 1905 paper. You might want to study quantum electrodynamics, not some crackpot nonsense on the internet.

 

 

You are

 

a) correct

 

 

b) WAY too kind

[Bart]

 

If the speed of light in air, shown by the Michelson-Morley experiment and in later experiments, is indeed constant in every direction and not depend on motion of the Earth, it is also legitimate to say that the speed of light measured in stationary water (~230 000 km/s), or glass (~170 000 km/s), also must be constant in each direction and independent of the speed of light source. If that were not true, it would have discovered long time ago, and then would be possible to construct universal speedmeters, based only on changes of the light speed, which is unreal.

 

On the other hand, if as shown, the speed of light is independent of the direction and of the movement of the light source, for each medium, then the light-clock uses eg. glass, in a rocket moving with any speed, will always indicate the same time as on Earth. Thus arguments of the special theory of relativity, about for example time dilation, are wrong.

 

 

This is utter nonsense. The premise of special relativity theory is that the speed of light in vacuum is the same to all observers. Special relativity says nothing about the speed of light through matter. Getting a complete picture of how light interacts with matter took another than 40 years after Einstein's 1905 paper. You might want to study quantum electrodynamics, not some crackpot nonsense on the internet.

 

 

 

 

Could you explain what is this nonsense? Do you think that the speed of light in glass or stationary water is not the same in all directions and is dependent on the motion of the Earth? When and how it was found?

 

Edited January 24, 2012 by Bart

[D H]

Could you explain what is this nonsense?

It's nonsense because the author is misinterpreting the Michelson Morley experiment and because his "unreal" phenomenon is very real. That the speed of light through a medium depends on the velocity of the medium with respect to the observer was first demonstrated in 1851 in the Fizeau experiment. The Fizeau experiment is an after the fact confirmation of special relativity.

[Bart]

It's nonsense because the author is misinterpreting the Michelson Morley experiment and because his "unreal" phenomenon is very real. That the speed of light through a medium depends on the velocity of the medium with respect to the observer was first demonstrated in 1851 in the Fizeau experiment. The Fizeau experiment is an after the fact confirmation of special relativity.

 

 

 

In the Fizeau experiment, the medium was in motion relative to the light source. Your explanation is not true for the medium without movement relative to the light source, so your arguments are wrong. If this were true, it could measure the speed of the Earth by measuring the differences in velocity of light in the glass in a direction parallel to the motion of the Earth and in the transverse direction.

 

 

Edited January 24, 2012 by Bart

[D H]

In the Fizeau experiment, the medium was in motion relative to the light source. Your explanation is not true for the medium without movement relative to the light source, so your arguments are wrong. If this were true, it could measure the speed of the Earth by measuring the differences in velocity of light in the glass in a direction parallel to the motion of the Earth and in the transverse direction.

 

Nonsense. I said nothing about the motion of the medium relative to the source because the motion of the light source is immaterial.

 

Re "it could measure the speed of the Earth": What is "it"?

 

Re "velocity of light in the glass": What glass?

 

 

Be a bit more transparent in your writing. You are paying so much attention to appearance (font and size) that your writing lacks substance.

[Bart]

Nonsense. I said nothing about the motion of the medium relative to the source because the motion of the light source is immaterial.

 

Re "it could measure the speed of the Earth": What is "it"?

 

Re "velocity of light in the glass": What glass?

 

 

Be a bit more transparent in your writing. You are paying so much attention to appearance (font and size) that your writing lacks substance.

 

Sorry DH, I repeat:

 

If this were true, we could measure e.g. the speed of rotation of the Earth, by measuring differences in velocity of light in a glass rod (flint 170 000 km / s) in the parallel direction to the Earth's movement and in the transverse direction to this movement. I hope it is clear enough, now.

Edited January 24, 2012 by Bart

[Klaynos]

!

Moderator Note

Moved to speculations.

Please do not reply to this mod action or note.

[D H]

f this were true, we could measure e.g. the speed of rotation of the Earth, by measuring differences in velocity of light in a glass rod (flint 170 000 km / s) in the parallel direction to the Earth's movement and in the transverse direction to this movement. I hope it is clear enough, now.

Clear as mud.

 

Describe your proposed experiment, in detail.

[Bart]

Clear as mud.

 

Describe your proposed experiment, in detail.

 

Sorry DH once more, I can not describe my question more detailed. Is is really so dificult to grasp the problem, I am asking?

 

Whether measurements of the speed of light in a glass rod (flint 170 000 km / s), will show the difference of speed, if the first measurement of the speed will be executed when the rod is in a position parallel to the speed of the Earth, and the second measurement, when the rod is in a position transverse to the motion of the Earth .

Does the speed of light in a glass rod (or other medium) depends on the motion of the Earth?

Edited January 25, 2012 by Bart

[D H]

Sorry DH once more, I can not describe my question more detailed. Is is really so dificult to grasp the problem, I am asking?

Yes, it is difficult to grasp because it is nonsense.

 

Whether measurements of the speed of light in a glass rod (flint 170 000 km / s), will show the difference of speed, if the first measurement of the speed will be executed when the rod is in a position parallel to the speed of the Earth, and the second measurement, when the rod is in a position transverse to the motion of the Earth .

Does the speed of light in a glass rod (or other medium) depends on the motion of the Earth?

Where is the observer, where is the rod, how long is the rod, what is the velocity of the rod with respect to the observer? How is the experiment to be performed? How are you measuring one-way speed of light in this rod?

[Bart]

Yes, it is difficult to grasp because it is nonsense.

 

 

Where is the observer, where is the rod, how long is the rod, what is the velocity of the rod with respect to the observer? How is the experiment to be performed? How are you measuring one-way speed of light in this rod?

 

 

Evrything is in a physics laboratory. The light source, the test apparatus, and the detector are all at rest with respect to each other (and the Earth.) The glass rod you can have as long as you need to answer the question.

[derek w]

Is my understanding correct that the Michelson-Morley experiment was an attempt to prove the existence or non-existence of a moving aether.And the result is it proves the non-existence of a moving aether.But what about the existence of a stationary aether?Relativity works ok in a stationary aether,or am I missing some point?

[D H]

Evrything is in a physics laboratory. The light source, the test apparatus, and the detector are all at rest with respect to each other (and the Earth.) The glass rod you can have as long as you need to answer the question.

Given that, your supposition in post #11, "If this were true, we could measure e.g. the speed of rotation of the Earth, by measuring differences in velocity of light in a glass rod (flint 170 000 km / s) in the parallel direction to the Earth's movement and in the transverse direction to this movement.", is incorrect.

 

You are the one making extraordinary claims. The burden of proof lies upon you to justify your claims.

 

 

 

Is my understanding correct that the Michelson-Morley experiment was an attempt to prove the existence or non-existence of a moving aether.And the result is it proves the non-existence of a moving aether.But what about the existence of a stationary aether?Relativity works ok in a stationary aether,or am I missing some point?

Stationary with respect to what?

 

It's important to keep the historical context of the Michelson-Morley experiment in mind. The purpose was to find the medium via which electromagnetic phenomenon propagate through vacuum. Maxwell's equations indicated that electromagnetic radiation was a wave phenomenon that somehow propagated through vacuum. All wave phenomena known to physicists at that time required some medium through which the wave could propagate. So what was this medium that enabled light to move from the Sun, the planets, and the remote stars to the Earth?

 

A stationary medium, one that moves with the Earth as it orbits the Sun, would make the Earth a very special place in the universe. It would also show up as some very weird (and never seen) variations in the light from the planets and the remote stars.

[Bart]

Given that, your supposition in post #11, "If this were true, we could measure e.g. the speed of rotation of the Earth, by measuring differences in velocity of light in a glass rod (flint 170 000 km / s) in the parallel direction to the Earth's movement and in the transverse direction to this movement.", is incorrect.

 

You are the one making extraordinary claims. The burden of proof lies upon you to justify your claims.

 

 

 

 

Since no one dared to answer this question, we can only assume that the matter lies elsewhere.

Because, regardless of whether for the case presented, the response will confirm or deny the unchanging speed of light in the glass rod, BOTH ANSWERS WILL DENY THE CREDIBILITY OF THE SR THEORY.

[swansont]

Is my understanding correct that the Michelson-Morley experiment was an attempt to prove the existence or non-existence of a moving aether.And the result is it proves the non-existence of a moving aether.But what about the existence of a stationary aether?Relativity works ok in a stationary aether,or am I missing some point?

 

Being stationary WRT the aether was dismissed with Bradley's observation of Stellar aberration around 1725. http://en.wikipedia.org/wiki/Aberration_of_light

 

If we were at rest WRT the aether, there would be no aberration. Instead, we see what we expect for our orbital motion.

 

Since no one dared to answer this question, we can only assume that the matter lies elsewhere.

Because, regardless of whether for the case presented, the response will confirm or deny the unchanging speed of light in the glass rod, BOTH ANSWERS WILL DENY THE CREDIBILITY OF THE SR THEORY.

 

It is up to you to explain, in detail, why this is so. I don't see how this happens, D H (I presume) doesn't see how this happens. Nobody "dared" answer your question, probably because it doesn't make sense to anyone.

[D H]

Since no one dared to answer this question, we can only assume that the matter lies elsewhere.

Because, regardless of whether for the case presented, the response will confirm or deny the unchanging speed of light in the glass rod, BOTH ANSWERS WILL DENY THE CREDIBILITY OF THE SR THEORY.

Oh please. Stating a bald assertion in ALL CAPS does not make it true. It is still a bald assertion.

 

You are the one making extraordinary claims. The burden falls entirely on you (not us!) to demonstrate with mathematics the validity of your claims and to suggest an experiment that will demonstrate the validity of your claims. You have done neither.

 

Special relativity has absolutely no problem with the speed of light through your glass rod being the same regardless of orientation of the rod. In fact, special relativity says that the orientation of your rod has no observable effect. (Note: General relativity says otherwise, but the rod would have to be unrealistically long to make the effect observable.)

 

It is up to you to explain, in detail, why this is so. I don't see how this happens, D H (I presume) doesn't see how this happens. Nobody "dared" answer your question, probably because it doesn't make sense to anyone.

You presume correctly.

Edited January 25, 2012 by D H

[Klaynos]

!

Moderator Note

Read the rules:

http://www.scienceforums.net/index.php?app=forums&module=forums&section=rules&f=29

Stating something doesn't make it true.

Back up your claims else this will be making a fast move to being closed.

[derek w]

I was thinking more along the lines of an aether that was stationary in respect to itself,not to anything else.An elastic aether that can be forced to warp,but return to its original status upon release(e.g.elastic).

[IM Egdall]

Sorry DH once more, I can not describe my question more detailed. Is is really so dificult to grasp the problem, I am asking?

 

Whether measurements of the speed of light in a glass rod (flint 170 000 km / s), will show the difference of speed, if the first measurement of the speed will be executed when the rod is in a position parallel to the speed of the Earth, and the second measurement, when the rod is in a position transverse to the motion of the Earth .

Does the speed of light in a glass rod (or other medium) depends on the motion of the Earth?

 

OK, I'll try to answer your question: The answer is no. The speed of light in a glass rod will show no difference, whether the rod is parallel to the Earth or perpendicular to the Earth. This result does not violate special relativity. Why? Because it is being performed in a single frame of reference. The source of the light, the glass rod, and the device which measures the speed of that light are all on the Earth at rest with respect to each other -- i.e. in a single frame of reference.

 

The motion of the Earth has no effect because the entire experiment and the Earth are moving together. This, in essence, is what Galileo said in his Dictum on uniform motion.

 

(There is a caviat here. We are assuming here the Earth is moving in uniform motion -- no change in speed and/or direction. The spinning of the Earth around its axis and the motion of the Earth in its curved orbit around the Sun are not uniform motion. However, there effects are so small in this experiment as to be considered negligible.)

Edited January 26, 2012 by IM Egdall

[Bart]

OK, I'll try to answer your question: The answer is no. The speed of light in a glass rod will show no difference, whether the rod is parallel to the Earth or perpendicular to the Earth. This result does not violate special relativity. Why? Because it is being performed in a single frame of reference. The source of the light, the glass rod, and the device which measures the speed of that light are all on the Earth at rest with respect to each other -- i.e. in a single frame of reference.

 

The motion of the Earth has no effect because the entire experiment and the Earth are moving together. This, in essence, is what Galileo said in his Dictum on uniform motion.

 

(There is a caviat here. We are assuming here the Earth is moving in uniform motion -- no change in speed and/or direction. The spinning of the Earth around its axis and the motion of the Earth in its curved orbit around the Sun are not uniform motion. However, there effects are so small in this experiment as to be considered negligible.)

 

Thank you IM for your reply. But if the speed is unchaged because the source of the light, the glass rod, and the device which measures the speed of that light are all on the Earth at rest with respect to each other -- i.e. in a single frame of reference, then it will be the same if all that stuff will be placed in a rocket and launch to space with the speed eg. 0,5 c. Am I right?