Speed of Light Experiments

[cos]

I have to disagree with the opinion being expressed here. I have half a dozen physics text books that deal with SR in my bookcase. Not a single one says that MMX ratifies SR. What some say is that the results of MMX are consistent with what SR predicts. Not the same thing.

According to the Oxford dictionary one of the definitions of 'ratifies' is 'agrees to [or with]' i.e. is consistent with.

 

I agree wtih Mike-from-the-Bronx. MMX is consistent with special relativity, but it does not ratify it. Good way of saying it.

I agree with the Oxford dictionary - 'ratify' - agree (i.e. be consistent) with.

Edited January 18, 2011 by cos

[swansont]

According to the Oxford dictionary one of the definitions of 'ratifies' is 'agrees to [or with]' i.e. is consistent with.

 

 

I agree with the Oxford dictionary - 'ratify' - agree (i.e. be consistent) with.

 

Which is one more example of why the dictionary is not a technical resource. Ratify has multiple definitions, one of them being (essentially) "making/confirming validity."

[John Cuthber]

OK, there's a debate about the meaning of the word "ratify", so use a different word.

MMX is consistent with SR. Does it prove it?

Is there a different system, like SR, but different in which the MMX would work?

 

If so are there any experiments which would distinguish between that system and SR?

 

Anyway, unless you can define the speed of a vacuum then I think my earlier point stands.

I can calculate C in a way that doesn't depend on my speed WRT anything.

Edited January 18, 2011 by John Cuthber

[IM Egdall]

Einstein's light postulate: The speed of light is independent of the speed of its source. This is a foundation of SR and validated in numerous experiments. In this situation, the MMX would give a null result (which it did).

 

Now what if the speed of light IS NOT independent of its source (just for the sake of argument). The MMX would still give the same null result. Why? Because the source of the light and the detector in the MMX are not moving with respect to each other. THey are in the same reference frame. (See my guns on a train argument above.)

 

So the MMX does not prove or disprove Einstein's light postulate.

 

The fact that the perpendicular beams of light went at the same speed no matter what the orientation of the set-up or time of year the experiment was conducted just showed that their is no ether. In all these cases, the source of the light beam and the detector were at rest with respect to each other.

Edited January 18, 2011 by I ME

[cos]

Which is one more example of why the dictionary is not a technical resource. Ratify has multiple definitions, one of them being (essentially) "making/confirming validity."

So to which 'technical resource' should one refer? My Chambers Science and Technology Dictionary does not include definitions of 'ratify'.

 

You write that ratify has multiple definitions - apparently according to some technical resource; is 'agree to or with' not one of those definitions?

[swansont]

So to which 'technical resource' should one refer? My Chambers Science and Technology Dictionary does not include definitions of 'ratify'.

 

You write that ratify has multiple definitions - apparently according to some technical resource; is 'agree to or with' not one of those definitions?

 

My point is that it's not good to say we don't agree when using one definition, but do agree when using another. If there's that much ambiguity, find another word.

[cos]

OK, there's a debate about the meaning of the word "ratify", so use a different word.

MMX is consistent with SR. Does it prove it?

I understand that it is a primary tenet of physics that no theory can be proven by experiment - only disproven.

 

I don't think it matters which word is used; people will tend to apply their own interpretation of same.

 

Is there a different system, like SR, but different in which the MMX would work?

 

If so are there any experiments which would distinguish between that system and SR?

My comments, and interest, are specifically in relation to SR and the MMX.

 

Anyway, unless you can define the speed of a vacuum then I think my earlier point stands.

I reiterate - my comments are specifically in relation to SR and the MMX neither of which make any reference to an impossible rate of travel of a vacuum. I prefer to restrict my comments to the subject on hand.

 

I can calculate C in a way that doesn't depend on my speed WRT anything.

Isn't that what SR shows? Doesn't SR show that one will 'always' calculate c irrespective of one's rate of travel relative to anything - including the light source?

 

In order to eliminate any potential confusion on my behalf it would be appreciated if you would quote the specific comments of mine to which you are referring.

[Klaynos]

So... the constant light speed postulate...

 

I'd suggest doing some reading around why that postulate is valid, I don't have the time to find reference right now, but have a look for evidence that maxwell's equations are valid in all frames... basically that physics is the same everywhere... I suspect there is evidence for this being the case in terms of satellites, and our models of stars...

[D H]

Isn't that what SR shows? Doesn't SR show that one will 'always' calculate c irrespective of one's rate of travel relative to anything - including the light source?

Special relativity doesn't show that the speed of light is constant. It assumes this is the case. Maxwell's equations show that this is the case from a theoretical perspective and a plethora of experiments show that this is the case from an observational perspective.

 

 

 

[cos]

Einstein's light postulate: The speed of light is independent of the speed of its source. This is a foundation of SR and validated in numerous experiments. In this situation, the MMX would give a null result (which it did).

The MMX did NOT give a null result with respect to SR's light postulate!

 

The null result of the MMX was that it endeavored to show that the speed of light in the planet's direction of spin in an aether would be affected by that medium, which it was not! Ergo null result!

 

As previously posted...I have a copy of a science documentary in which Michelson himself proudly declares that his experiment validated the veracity of SR's constancy of light postulate. It is noted that there have been no responses to that comment.

 

It is claimed, in many books by academically relevantly qualified authors, that the MMX validated/ratified/confirmed/'proved'/suggested/implied [choose whichever word you believe is appropriate] the veracity of SR's constancy of light postulate.

 

I have seen no book written by an academically relevantly qualified author wherein they suggest that the MMX did not validate/ratify/confirm/'prove'/suggest/imply [choose whichever word you believe is appropriate] the veracity of SR's constancy of light postulate.

 

Now what if the speed of light IS NOT independent of its source (just for the sake of argument). The MMX would still give the same null result. Why? Because the source of the light and the detector in the MMX are not moving with respect to each other. THey are in the same reference frame. (See my guns on a train argument above.)

 

So the MMX does not prove or disprove Einstein's light postulate.

 

The fact that the perpendicular beams of light went at the same speed no matter what the orientation of the set-up or time of year the experiment was conducted just showed that their is no ether. In all these cases, the source of the light beam and the detector were at rest with respect to each other.

I pointed out in a previous post that I WHOLEHEARTEDLY, UNRESERVEDLY, BELIEVE THAT THE MMX DID NOT PROVE OR SHOW THAT THE SPEED OF LIGHT IS CONSTANT RELATIVE TO ALL (INERTIAL) REFERENCE FRAMES.

 

The previously referred to documentary features a cartoon showing Einstein as a passenger on a train that it traveling past the (MMX) light source however whilst such a vehicle may have been moving past Michelson's basement there appears to be no record of measurements made by any of of its passengers or crew.

 

It is, in my opinion, ludicrous for anyone to suggest, as do some, that the MMX supported SR from the point of view of an observer located on the sun!

 

I find it particularly galling that people attempt to denigrate my ideas without the courtesy of responding to my comments such as that one.

Edited January 19, 2011 by cos

[cos]

Special relativity doesn't show that the speed of light is constant. It assumes this is the case.

Again we have alternate meanings of a word e.g. 'show'.

 

Oxford Dictionary - 'show'; cause to be visible/exhibit for scrutiny/put on display/present for public viewing/indicate (a particular measurement).

 

If I open a book that contains (extracts/quotations from) special theory that page shows/exhibits/displays/presents the words "...light is always propagated in empty space with a definite velocity c...." which Einstein had previously stated was a postulate.

 

Oxford Dictionary - 'postulate'; a thing suggested or assumed as true as the basis for reasoning, discussion, or belief.

 

It is my understanding that the concept of a constant speed of light was officially accepted by the international scientific community before SR was published.

 

In his introduction to the General Theory of Relativity Einstein wrote: "The PRINCIPLE of the constancy of the vacuum speed of light..."

 

Oxford Dictionary - 'principle'; a general scientific theorem or law. 'Theorem'; a general proposition not self-evident but proved by a chain of reasoning; a truth established by means of accepted truths.

 

In his book 'Relativity, the Special and General Theory' Einstein wrote: "...our result shows that..the law of the constancy of light..."

 

It seems that Einstein believed that the so-called constancy of light speed as indicated in SR is a law which to my way of thinking is a much stronger, positive term than 'conjecture' or 'assumption' or 'postulate'.

 

Perhaps you could let me know the title of the technical resource from which physicists make their determinations as to which 'acceptable', 'applicable', 'official', 'unique' translation of a particular word is the 'real' version?

 

Maxwell's equations show that this is the case from a theoretical perspective...

I am not discussing Maxwell’s theoretical ideas but specifically SR and the MMX.

 

...and a plethora of experiments show that this is the case from an observational perspective.

It is my understanding that whilst a theory may appear to have been ratified by, for example, a plethora of experiments it is a primary tenet of physics that it only takes one negative (repeatable) experiment to invalidate any theory.

Edited January 19, 2011 by cos

[Mike-from-the-Bronx]

I pointed out in a previous post that I WHOLEHEARTEDLY, UNRESERVEDLY, BELIEVE THAT THE MMX DID NOT PROVE OR SHOW THAT THE SPEED OF LIGHT IS CONSTANT RELATIVE TO ALL (INERTIAL) REFERENCE FRAMES.

 

 

 

The Original Poster of this thread was asking for examples of the measurement of the speed of light. If anyone posted the opinion that MMX measured the speed of light they are wrong. Unless I have misunderstood the intent of the OP, any further discussion of MMX is really off-topic. You seem to have an important issue that you would like to discuss with regards to MMX. I have seen such issues resolved in the course of discussing another subject. But, frustratingly, in this particular case that is not happening. So I would suggest starting a thread of your own and in that thread asking posters to stay on your topic.

[Klaynos]

Further to the paper I posted earlier, which discusses tests for Lorentz invariance, which is what is pretty much being discussed here I'd also suggest people read:

 

http://mathnet.preprints.org/EMIS/journals/LRG/Articles/lrr-2005-5/

[cos]

My point is that it's not good to say we don't agree when using one definition, but do agree when using another. If there's that much ambiguity, find another word.

And what is the possibility of that other word also having multiple definitions?

 

So to which 'technical resource' should one refer?

On the basis of your not having responded to that question am I to assume that there is no such technical resource?

 

The Original Poster of this thread was asking for examples of the measurement of the speed of light.

The original poster of this thread was not asking for examples of the measurement of the speed of light per se but was inquiring about an experiment which showed that the speed of light is a constant.

 

If anyone posted the opinion that MMX measured the speed of light they are wrong.

No-one posted that opinion!

 

Conversely, the MMX ‘measured’ (determined) that the speed of light in an inertial reference frame appears to be isotropic. This does not involve determinations of the speed of respective beams per se but shows that beams which are projected in various directions do not end up being fringe shifted.

 

In #6 TonyMcC responded that the MMX tried to prove that the speed of light was not a constant no doubt (I believe correctly) assuming that this was ‘the’ experiment to which the OP referred.

 

Unless I have misunderstood the intent of the OP, any further discussion of MMX is really off-topic.

You obviously have misunderstood the intent of the OP.

 

Further discussion of the MMX is in direct response to the OP!

 

You seem to have an important issue that you would like to discuss with regards to MMX. I have seen such issues resolved in the course of discussing another subject. But, frustratingly, in this particular case that is not happening. So I would suggest starting a thread of your own and in that thread asking posters to stay on your topic.

Your assumption and dismissive suggestion are inappropriate ergo off-topic.

[Mike-from-the-Bronx]

Your assumption and dismissive suggestion are inappropriate ergo off-topic.

 

 

I'm sorry if my post offended you. I was really trying to be helpful. I know the answers to your issues but I don't care to participate any more in this thread.

Edited January 22, 2011 by Mike-from-the-Bronx

[cos]

I'm sorry if my post offended you. I was really trying to be helpful.

Then woe betide those you seek to denigrate and confuse.

 

I know the answers to your issues....

You have had ample opportunity to contribute to the single issue raised by the OP and my response to same.

 

....but I don't care to participate any more in this thread.

That is the gist of the suggestion in my last message.

[D H]

What windmill are you tilting at, cos?

[alpha2cen]

Sorry, I'm getting my interferometry experiments muddled up

 

http://en.wikipedia....i/Sagnac_effect

I meant this one.

 

At the speed of the light experiment, is speed reduction by surface electron of the mirror not detected?

And, is the Earth gravity and magnetic line effect removed from the experiment?

Was the light source test done exactly, i.e., single polarized, highly purified single direction, single wave length and result response time?

it is no problem at low significant figure data, but it's effect is not neglectful at high significant figure data.

Edited January 23, 2011 by alpha2cen

[cos]

What windmill are you tilting at, cos?

On the basis that this particular windmill has seemingly been toppled I wonder if it might be possible to discuss the topic rather than continuing to inappropriately allocate space and time to philosophical debate?

[D H]

So, you are smarter than multiple generations of physicists? Give me a break.

[cos]

So, you are smarter than multiple generations of physicists? Give me a break.

You are adamant that this discussion should continue sans any physics content aren't you? I shall respond in kind.

 

The 'windmill' to which I referred was ignorant (as in seemingly not having read/understood the OP) responses to my messages.

 

I have received many responses in several groups purporting to be directed toward 'helping' but, in reality, being heavily veiled attempts to discredit/besmirch ideas.

 

It is that deplorable and cowardly action which I see as being analogous to windmills placed in strategic locations.

[Cap'n Refsmmat]

Perhaps if you were less argumentative and rude, you'd receive more helpful responses. Could you please cut it out?

[cos]

Perhaps if you were less argumentative and rude, you'd receive more helpful responses. Could you please cut it out?

Any of my comments that are deemed to be grossly argumentative and rude are inevitably the result of my having been submitted to that form of treatment from those to whom I am responding.

 

I see no reason for responders to post such material in the first instance.

[Cap'n Refsmmat]

There is a difference between thinking someone is wrong and being rude to them. There is no excuse for the latter.

 

It seems to me you're picking fights where none exists.

 

In any case, back on topic please.

[cos]

On the basis that there are no relevant responses to which I should reply I have no further comment to make.