# SR and one-way speed of light tests

wisp
One-way speed of light test.
I would be grateful for any views you might have on what is a simple test to measure lights speed one-way on the surface of the Earth. The purpose of this test is to prove that the speed of light is affected by the ether wind and as a consequence Einstein's SR is wrong. This test is unique in that it eliminates clock synchronization errors and I believe it has never been done!

Let u be the speed at which the Earth moves through the ether, its orbit speed of 30000m/s.

Two clocks A and B are placed on the Earth's surface 10km apart. When the clocks line up in the direction of the Earth's orbit, a laser fires from A to B. Clock A records the start time and B records the stop time. The time difference between the two clocks is

td(1) = sync error + 10000/(c-u) seconds

Assuming a small synchronization error exists between them.

12 hours later the clocks line up again parallel to the Earth's orbit, but this time in the opposite direction. The laser again fires from A to B and the time difference recorded is td(2), where

td(2) = sync error + 10000/(c+u) seconds

The two readings are then compared.

Now if SR is true the difference between the times should be zero, as the speed of light is unaffected by the ether - if it exists.

But I believe that the speed of the Earth through the ether will result in light travelling at different speeds and td(1)-td(2) = 6.7nS

This is a simple test and some may consider it irrelevant, as there are many two-way tests that supports SR. But think very carefully, if two-way tests cannot detect the ether then a one-way test must be the answer and to my knowledge no such one-way speed of light test has been done!

Mentor
Originally posted by wisp
This is a simple test and some may consider it irrelevant, as there are many two-way tests that supports SR. But think very carefully, if two-way tests cannot detect the ether then a one-way test must be the answer and to my knowledge no such one-way speed of light test has been done!
Must? You are assuming the result before doing the test. Perhaps tests we have done don't show the result you are looking for because your theory is wrong?

A one-way test of the speed of light is done every time someone flips on a gps reciever.

Jonathan
How can that be Russ? Whenever anyone turns on a gps, they never, nor could they, see if there is a time difference between outgoing and income signals from a satelite. It should be noted that the solar system, and galaxy are both moving through space too, so you'd have to take their movement into account while doing the experiment. However, I don't see how a one way test would make a difference. If an ether exists, the experiments show that light doesn't notice.

Staff Emeritus
Gold Member
I work with an engineer who is in the process of setting up a femtosec pulse length laser, now all you have to do is provide me with a reason why the speed of light would aveage c but not be c in both directions on a trip to a mirror and back.

Please provide me with the argument. I could possibly convince them to do a one way speed of light experiment if there is a concieveable reason we should take valuable equipment and personell time to do such an experiment.

By the way the way I read your reasoning, Michelson & Morely did your experiment over 100yrs ago. In spite of having suffciet resolultion to measure the variations due to what you are citing, it was not found.

Again,What is the physics behind the variations you speak of? We need a theory to test, what is your prediction of the magnetude of the variation and in what direction should we look?

Nacho
Michelson-Morley didn't exactly do the tests to prove this wrong. It was a two-way test, as each leg of the interferometer had mirrors on the end, reflecting the light back from each leg to a common point.

But, they rotated the whole apparatus, at least 90 degrees, and so there can't be a directional difference in the speed of light.

But .. they only rotated it in a plane, not on every axis of a sphere. I'm not suggesting there could be differences on different axis .. only enough wiggle room left to say it could be. Have to have a whole lot of conspiracies lined up, more than SR gives us, to show positive results here. i.e., if the direction effected the speed, it would also have to effect the wavelength.

wisp
If I had access to two atomic clocks, a lasers and light gate triggers I would seriously do this experiment. But I don't work in physics. I have spent alot of my time and money developing a new theory (wisp unification theory - http://www.kevin.harkess.btinternet.co.uk ) that shows this test will give a positive difference result of 6.7nS over 10km.
If anyone wants to use my theory as a reason to justify doing this, they're welcome. The theory is free to download.
Chapter 7 - section 7.7 shows why the two-way MM experiment failed. It's due to a thing I call jiggle.
The GPS data travelling back and forth has too many variables to determine any differences in journey times. I think that signals are delayed by approx 20mS each way and internet traffic gets another 80mS delay. I don't believe anyone has conducted a true one-way GPS test. GPS also use Einstein's clock synchronization method, which is biased in favour of SR.
This one-way test has the advantage of cancelling any clock sync delays, which is important.

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Staff Emeritus
Gold Member
Since it appears that the purpose here is to promote your own theory, Off to TD this thread goes.

Mentor
Originally posted by Jonathan
How can that be Russ? Whenever anyone turns on a gps, they never, nor could they, see if there is a time difference between outgoing and income signals from a satelite. It should be noted that the solar system, and galaxy are both moving through space too, so you'd have to take their movement into account while doing the experiment. However, I don't see how a one way test would make a difference. If an ether exists, the experiments show that light doesn't notice.
GPS is one way - they gps recievers are recievers only. They work by recieving signals from 4 or more satellites and comparing the time stamps on the signals to calculate the distance from each. If the speed of light varied, it wouldn't work.

In addition, since the speed of light IS constant and this affects the flow of TIME, the gps system takes this effect into account.

The GPS data travelling back and forth has too many variables to determine any differences in journey times. I think that signals are delayed by approx 20mS each way and internet traffic gets another 80mS delay. I don't believe anyone has conducted a true one-way GPS test. GPS also use Einstein's clock synchronization method, which is biased in favour of SR.
I don't understand. You acknowledge that GPS accounts for/uses relativity, but you're saying that since it uses relativity it can't prove relativity? Thats how science works!!

Or maybe you just don't understand how it works. Too many variables? Listen, GPS WORKS. If there were too many variables to do the needed calculations to make the necessary relativistic corrections, GPS WOULD NOT WORK.

And again: GPS signals are ONE WAY ONLY. The recievers do not transmit any information back to the satellites.

Civilan GPS is accurate to about 10m. Light travels 10m in 1/30,000,000 second. The transit time from a satellite 300km away is 1/1,000sec. So if the speed of light were to vary by more than .003%, then that would need to be taken into account. It doesn't and it isn't.

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I find this intriguing. I read a tiny bit of this so called wisp theory. So, relativity was wrong because it violates commonsense? I see. Paradoxes exist? Whoa, I must have missed those. But what's this...you say certain things, like the speed of lights (and you add transverse forces of some sort) are unaffected by motion and are absolute regardless of who is observing. But doesn't this mean then that what you are trying to test is pointless? Why, yes, yes it does beacuse light would be uneffected by this so called ether.

By the way, someone said they tested it only on a plane. That's all you needed. The plane was the general one that earth's orbit traverses, and hence the one that would create the most effect if it existed.

wisp
The reference to my theory was to supply "intergral" with some support material to give a convincing argument to do the test; it's not there to distract this thread.
I agree that on basic calculations "russ_watters" figures show that if the speed of light is constant the results seem OK.
All things being taken into account there seems to be no reason to doubt that the figures work out.
But it can be shown that the GPS system will also work if the Earth's motion through the ether affects lights relative speed.
GPS satellite orbits are determined by their orbital period (approx 11hrs 58mins), their height (approx 26600km - 4 Earth radii), their orbital speed (about 3.9km/s), and the orbital eccentricity (typically less than 1%). Data from T.V.Flanders "What the Global Positioning System Tells Us about Relativity".

Lets assume that a GPS was setup using clocks synchronized to an absolute reference clock. And assume that the exact orbit positions of the satellites are known.
If the speed of the Earth through the ether affected lights relative speed, we would still be able to have a working system.

Now if someone applied SR with Einstein's clock synchronization, we would see immediately that things were not right because the clocks are out.

But if we did not record the satellites exact positions, we could say that if we assume the satellite orbits are shifted forwards by 2.6km in the direction of the Earth's orbital motion, then SR works out OK.

The difference between the two systems is only a question of orbital shift. It is not related to orbital period, as a shift will not affect this value.
I doubt that the exact positions of the satellites have been verified by means of an optical check. Two Earth based telescopes would need to make simultaneous measurements to within fractions of an arc second to pinpoint the satellites exact position.
This data would then have to be compared with data predicted by GPS.

The point I am making is that the GPS system doesn't prove that the speed of light is constant. The GPS is able to track positions on the Earth to about 30cm, but there are many ways that this can be achieved even if the true orbital positions were all shifted by 2.6km.

What are the advantages of doing this Earth based one-way test.
1. It has never been done before. Whatever the result, it will - if done properly - be recorded in history as the first test of its kind.
2. It may change science if the difference result is positive.
3. It is a simple test that will either strengthen SR are destroy it.

I am still learning about GPS. The more I look into it the more I'm convinced that GPS is not a test for the speed of light.

Mentor
Originally posted by wisp
I doubt that the exact positions of the satellites have been verified by means of an optical check.
In order to make the system give positions accurate to 10m, the position of each satellite must be known to better than 10m precision.
Now if someone applied SR with Einstein's clock synchronization, we would see immediately that things were not right because the clocks are out.
Clocks on GPS satellites DO vary according to SR.

This is as far as I'm going to go, wisp. You have a TON to learn about Relativity and its implications. I really recommend you read a book on it.

wisp
Thanks for the reply. I have read may books on special relativity and don't consider it a difficult subject. However, I'm not going to persue this GPS discussion futher. I will wait until someone does this test and see what the results are.

Thanks

Your experiment is essentially not going to reveal anything new. The MM experiment would have detected ANY drift effect due to the ether.

http://scienceworld.wolfram.com/physics/Michelson-MorleyExperiment.html

One should read that and study the diagram even to see why your one way test as you call it was more or less included in the MM experiment (in other words, the light did bounce back from the direction it came. IF there was any ether difference, a distinct interference pattern would have occured).

Nacho
... The MM experiment would have detected ANY drift effect due to the ether.

Hmm, ANY drift? What if the EMF actually (what word do I use??) bent/modified/effected/drifted the ether? Or, the ether existed but was effected in such a way that makes it look like C is constant?

Hard to believe? Yes, but look at something else. Now adays we all talk about the electromagnetic field. Just how is that different than an ether? I don't see it as any different. I see it as just calling an ether by another name, maybe with a few different properties.

The MM experiment didn't prove there wasn't an ether; only that an ether wasn't needed to formulate a theory behind observations.

wimms
Originally posted by wisp
I doubt that the exact positions of the satellites have been verified by means of an optical check.
not only have they checked them optically, they actually built several observatories across the globe to monitor them 24/7/365 for exactly that only!
read this for short: http://www.trimble.com/gps/how.html [Broken]

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Mentor
Originally posted by Nacho
Now adays we all talk about the electromagnetic field. Just how is that different than an ether? I don't see it as any different. I see it as just calling an ether by another name, maybe with a few different properties.
Yeah, you have no idea what an electromagnetic field is. Then again, a rose by another name and with different properties would be - a petunia.

. I will wait until someone does this test and see what the results are.
lol

FZ+
Originally posted by wisp
Data from T.V.Flanders "What the Global Positioning System Tells Us about Relativity".

You mean T Von Flandern? I thought that name was familiar.

You're in luck, there is a wealth of information documenting Flandern's errors regarding relativity. Here's an article about his claims about GPS. And how they are complete rubbish.

http://math.ucr.edu/home/baez/RelWWW/wrong.html#gps [Broken]
Enjoy!

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Nacho
Yeah, you have no idea what an electromagnetic field is. Then again, a rose by another name and with different properties would be - a petunia.

Seems you woke up a bit cranky from your nap.

Cranky, but accurate. The electromagnetic field is by NO means anything like an ether.

Mentor
Originally posted by FZ+
You mean T Von Flandern? I thought that name was familiar.

You're in luck, there is a wealth of information documenting Flandern's errors regarding relativity. Here's an article about his claims about GPS. And how they are complete rubbish.

http://math.ucr.edu/home/baez/RelWWW/wrong.html#gps [Broken]
Enjoy!
Great link - much more in depth about relativistic effects on GPS than I had ever seen.
Seems you woke up a bit cranky from your nap.
Rough day + instinctive low tolerance for crap.

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Nacho
Cranky, but accurate. The electromagnetic field is by NO means anything like an ether.

I don't see a great difference. The ether was thought of as a material thing in space, a medium for forces to move through -- the medium part pretty well discredited. Fields are more abstract, quantities here, potentials there, caused by the presence of a particles. But nowhere in space can the field be separated from space. The gravitational field doesn't only effect particles, it is even said to effect/curve space.

What property of space is being effected? Fields are a backdoor approach, having effects on every point in space and space itself rather a property of space conducting forces.

I tend to think of an ether (should it exist) as not a medium filling space, but space itself .. a structure that space has (maybe pure geometry). They couldn't be seperated.

Nacho
Rough day + instinctive low tolerance for crap.

Then maybe all you need to do is chill out a bit -- relax a bit from the rough day, before you post.

Or take that nap. Maybe it'll help.

Originally posted by Nacho
I don't see a great difference. The ether was thought of as a material thing in space, a medium for forces to move through -- the medium part pretty well discredited. Fields are more abstract, quantities here, potentials there, caused by the presence of a particles. But nowhere in space can the field be separated from space. The gravitational field doesn't only effect particles, it is even said to effect/curve space.

What property of space is being effected? Fields are a backdoor approach, having effects on every point in space and space itself rather a property of space conducting forces.

I tend to think of an ether (should it exist) as not a medium filling space, but space itself .. a structure that space has (maybe pure geometry). They couldn't be seperated.

But then that wouldn't be an ether at all...that would be just spacetime. Plain old vanilla spacetime.

Fields are not what the ether is. Rather a field is a handy mathematical tool for describing forces at any point in space. The ether was proposed to be a fluid like thing that electromagnetic waves could traverse through. An electromagnetic field is not something that would satisfy this condition.

wisp
wimms
Thanks for this reference source; I was hoping to find something like this. I will study it closely and see if there is any possible reason why the proposed one-way test would not get covered by this.

The MM experiment fails on the Earth's surface due to a thing I call jiggle - random motions of the ether occurs at right angles to the direction of the Earth's motion as it moves through the ether. It is the electromagnetic property of light that gets affected and this slows light down in the perpendicular arm of the MM apparatus. Hence a null result.

Note: If a larger version of the MM experiment is done using the GPS satellites (in space and away from Earth's jiggle motion effects). An error of L*v^2/c^3 would result = 0.9nS. Where
L = 26600km, v=30km/s (Earth's orbit speed - motion through ether).
I know GPS clocks suffer from a random unexplained 1nS error? Maybe a connection, I don't know. But it's interesting anyway.

Originally posted by wisp
wimms
Thanks for this reference source; I was hoping to find something like this. I will study it closely and see if there is any possible reason why the proposed one-way test would not get covered by this.

The MM experiment fails on the Earth's surface due to a thing I call jiggle - random motions of the ether occurs at right angles to the direction of the Earth's motion as it moves through the ether. It is the electromagnetic property of light that gets affected and this slows light down in the perpendicular arm of the MM apparatus. Hence a null result.

Note: If a larger version of the MM experiment is done using the GPS satellites (in space and away from Earth's jiggle motion effects). An error of L*v^2/c^3 would result = 0.9nS. Where
L = 26600km, v=30km/s (Earth's orbit speed - motion through ether).
I know GPS clocks suffer from a random unexplained 1nS error? Maybe a connection, I don't know. But it's interesting anyway.

So, let me get this straight. You say that the earth's motion through this ether creates a 'jiggle' that slows down the light beam that is traveling perpindicular to the earth's motion? And what praytell would make any ether do this? In essence you are saying that the 'jiggle' creates enough perpindicular drag to exactly match the drag created by the earth's motion through the ether perpindicularly. If that is the case, then how can we know which way we are moving using the ether as a frame of reference? If two perpindicular directions cause exact changes in a beam of light what would happen then?

Also, what about all experiments that are used to detect gravity waves? Such as LIGO or VIGO. They bounce laser beams back and forth on mirrors many times (very very sensitive lasers with extremely accurate clocks if you will). This boils down to a one way test right there. They use 3 lasers to create a triangle, however each indidividual laser leg traverses back and forth many times. If any direction at all caused any drag or "jiggle" the laser light would interfere with at least one of the other lights at the mirrors registering something was afoot.

Nor let us forget that these things are set up with the time it would take light traveling at c to traverse the distance required. If the light slowed down any from an ether effect, the apparatus would suffer continual error in it.

Also, one consequence of your theory then is that since light is no longer a universal constant, it seems one can indeed catch up with a light beam, and observe it stationary. Stationary light waves are forbidden by Maxwell's electromagnetic equations (and no, those experiments in which they say we stop light are not actually freezing a beam of light as the popular media would suggest...just in case anyone tries to bring that up). You also claim that physical laws are different for different frames of reference. Ok, so why is it that particles moving at extremely high velocities do not experience different laws? Regardless of our inertial frame we would observe other frames having much different effects than they would in ours. Yet all we observe is that these frames that have a higher velocity are in exact accord with relativity...that is, they occur slower because the entity is traveling at relativistic velocities.

Not to mention, since an electromagnetic wave is a transverse wave, it can propagate through itself (that is it is essentially two waves fluctuating about each other...an electric wave fluctuating around a magnetic wave transversely). No ether required.

Mentor
But then that wouldn't be an ether at all...that would be just spacetime. Plain old vanilla spacetime.

Fields are not what the ether is. Rather a field is a handy mathematical tool for describing forces at any point in space. The ether was proposed to be a fluid like thing that electromagnetic waves could traverse through. An electromagnetic field is not something that would satisfy this condition.
Let me try an analogy: a boat towing a barge through a river. The boat is a planet, the barge is its moon, and the river is the ether. The field is the tow rope.

Or is this better: sound is the field, air is the ether. Sound travels in air, but sound itself is not air.
I know GPS clocks suffer from a random unexplained 1nS error? Maybe a connection, I don't know.
They call it random for a reason. Its not connected to anything other than the inherrent limitation of the clock.

wisp
wimms
I looked at the trimble site on GPS and it's very good. But it doesn't challenge my earlier statement:

The difference between the two systems (SR and ether based)is only a question of orbital shift. It is not related to orbital period, as a shift will not affect this value.
I doubt that the exact positions of the satellites have been verified by means of an optical check. Two Earth based telescopes would need to make simultaneous measurements to within fractions of an arc second to pinpoint the satellites exact position.
This data would then have to be compared with data predicted by GPS. [Unquote]

The way that the satellites distances are measured in GPS is based on the speed of light being c, not (c+v) or (c-v). And there is no accurate optical check to verify this. (v = Earth's orbit speed).

The trimble site said that the "triangulation" method used is not true triangulation because angles are not measured. It's more a method of trilateration. Also the US Dept of Defence track GPS satellites using radar and light speed c (not observational checks).

So we cannot prove precisely where the satellites are, it's based only on prediction using time delays and c. Advanced error correction techniques can produce pinpoint position accurancies for Earth's surface mapping, but the position of the satellites has not been accurately optically checked.

I still say that GPS is not proof that the speed of light is constant, and that the proposed one-way test will produce a positive result.

wisp
In response to you last message.

Any MM type experiments cannot measure the ether flow, only a one-way test can. LIGO and VIGO are essentially two-way tests and will not show a change in light speed due to ether flow. How they work when changes to spacetime or ether occur as gravity waves pass by is another issue.

Jiggle is not ether drag. The ether gets shaken back and forth as matter passes by, it doesn't get dragged along.

Quote:
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Nor let us forget that these things are set up with the time it would take light travelling at c to traverse the distance required. If the light slowed down any from an ether effect, the apparatus would suffer continual error in it.
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If an accurate optical check were to be done on a satellites position this error would show. All GPS satellite positions are predicted using
time delays and with the speed of light set to c. This is not real proof. Also the error corrections in the system are not affected by this "orbital shift" offset, and errors are reset every hour - fine tunning.

re: Maxwell's eqns.
Light speed is constant relative to the ether. As the Earth moves through the ether, the speed of light relative to use changes.
Maxwell built his equation sets on the basis that a fluid medium existed that had elastic properties. His equations can be considered
solely as mathematical tools that will work with or without an ether. It is believed that the Lorentz Force Law is not supported by an ether, but equation using jiggle show that an ether can support it.

You could catch up with the speed of light, but you would suffer effects other than time dilation, which would be unpleasant.
In terms of witnessing relativistic effects in different frames, we are relativistically speaking stationary. If a test is carried out simultaneously on the Earth and aboard a craft moving fast through the ether. Both tests (locally) would conform to all know laws of physics.
Only if an Earth observer could see the test happen in the moving craft would he/she notice it was running slower. The craft observer would see the Earth test running faster.
They would then know a difference existed and the laws of physics change outside their local space.

The electromagnetic wave oscillates with its electric and magnetic components working together. But this would work just as well in an ether space. Not as simple as water waves, but it's not impossible. Suppose the ether is stretched (electric component) in one direction creating physical changes in its density.
The ether may respond by shifting the pattern of the light wave transversley (magnetic component). This is a bit complicated to visualize, but it's not impossible for the ether to support light waves.

Mentor
Originally posted by wisp
I still say that GPS is not proof that the speed of light is constant, and that the proposed one-way test will produce a positive result.
I give up. We've explained so many times and in so many ways the various errors and misconceptions you are operating from. You are wrong on so many levels. Good luck.

wisp
The De Witte experiment
In 1991, Roland De Witte carried out a one-way electrical experiment that proved that the Earth moves through the ether. The duration of the test was 178 days and it's proof that the Earth is affected by an ether wind of galactic origin.

A 5Mhz signal from clock A is passed down a coaxial cable of length 1.5km to clock B. The signals were compared using a digital phase comparator (like those used in PLL). The result was affected by the Earth's rotation and had a period of 23hr 56min +/- 25s and is therefore the sidereal day. For further information on this test, see http://www.lns.cornell.edu/spr/1998-12/thrd3.html and http://home.planetinternet.be/~pin30390/belgacom.htm [Broken]

The implications of this test are that the proposed one-way light speed test will produce a difference result that is greater than 6.7nS due to a galactic ether flow component, and that the galactic flow must be greater than 30km/s (Earth's orbit speed).

The angle (theta) that the Earth's orbit makes with the galactic ether flow will determine the change in the relative speed of light (u*cos theta). Of course, if theta = 90 degrees then a null result will occur, but the chances of this happening is very small.

Like the De Witte experiment the measurements with light should be run continuously to determine maximum and minimum values.

I would imagine that Roland has stopped trying to push his ideas on the ether, due to lack of support. But I do support his test and believe it's a first real test that the ether exists.

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Must be a local phenomena. Otherwise a lot more telecommunications businesses would report some trouble in syncronyzing their clocks...hell, if nothing else then for sure scientific laboratories could not merely use c value of light to syncronize experiments in different laboratories (i.e. in a lab I toured in, they have to take into account the travel time of a signal to another lab across the globe to make as much of a timeing as possible). They always use light speed = c no matter when, and always get precise results.

Must be a local ether centered around his locale

wisp
If the variation detected was local it would have a cyclic period of 24 hours - one calendar day. But its period was 23hrs 56mins - one sidereal day. This rules out a local factor. Whatever is causing the change has to be in the direction of the distant stars, i.e. of galactic origin.
This result is not what I would've expected. But it strengthens the argument in doing a proper one-way light speed test. It suggests that the result will be >6.7nS. But like the De Witte test, the laser should fire continuously over several weeks to record maximum/minimum values.
Note: because of the great speed of light, clock sync error would not show in telecommunications systems. The errors are there, but they are too small to show. This test will prove that the relative speed of light changes.

First off, why would it being local necessitate it be a 24 hour period??

And second of all, this was not the run of the mill telecommunications system.

Third, a system such as the one you cite is prone to many various impurities over the course of weeks. Even if it is burried underground, things such as lunar tidal forces can cause some distortions to occur, as can power usage, and other cycles.

Mentor
Originally posted by wisp
But it strengthens the argument in doing a proper one-way light speed test. It suggests that the result will be >6.7nS.
That is well within the ability of the GPS system to detect. I looked over the experiment and I can't claim I understand it completely - but it looks like he's stretching the precision of his apparatus. His measurements are likely the result of experimental error.

I realize this is the sort of experiment and paper you would jump on, but PLEASE consider the credibility of the source. Has the paper been peer-reviewed and published? If no, consider that there is probably a REASON why it hasn't been published: its flawed.

Incidentally, he mentions GPS - he says the failure of GPS to detect his effect is due to the variation of the speed of light exactly cancelling the time dilation for the signal transit time. Those damn laws of the universe are conspiring against us again. Except that that ignores the other part of the time dilation: The part where the time dilation causes the clocks to become out of sync with each other. Sorry, self-contradictory arguement.

And again - if there was an aether wind, the MM experiment would have detected it, your understanding of the MM experiment to the contrary.

Wisp, you're repeating the same flawed arguements over and over again. That doesn't make them right.

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That's right, it's also a lesson in SR- the MM interferometer would've detected a difference in the fringes 100 years ago.