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Anisotropy of the speed of light?

  1. Apr 10, 2006 #1


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    Carlos. E. Navia and Carlos. R. A. Augusto's paper:
    (Instituto de F´ısica Universidade Federal Fluminense, 24210-130, Niter´oi, RJ, Brazil) Amplified Doppler shift observed in diffraction images as function of the COBE "ether drift" direction
    Can this be duplicated and explained or refuted?

    I am very sceptical (and note it is not April 1st!) that it is actually an anisotropic velocity of light as it is so large, ~ 370 km.sec-1, and would have been picked up by all investigators since Michelson and Morley. However they may just be measuring another effect that is coupled to our motion relative to the CMB isotropic frame.

    Last edited: Apr 10, 2006
  2. jcsd
  3. Apr 10, 2006 #2

    The paper contains a mistake that has become classical. The curve that represents the SRT prediction is not a horizontal line stuck on 0 as the authors describe but a sine wave caused by the diurnal variation of the lab speed. Like Maurice Alllais, like Dayton Miller before him, what they are really measuring is this diurnal variation.
    There are many experiments that prove that the light speed is istropic.
    See here, in this forum:


    Gagnon, Krisher, C.M. Will have all run experiments that prove it. I have copies of the papers if you want them.
  4. Apr 10, 2006 #3


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    Paraphrasing the paper ([bracketed] comments are mine): "...well, we were only able to record ten minutes worth of data [the boss (the "author's" sister?) came back from her break sooner than they expected?], and this was while the TUPI muon telescope [with his sister's laser pointer taped inside the shell piggyback-style?] was slewing between horizontal and vertical." :bugeye:

    Quoting directly from page 4: "So far, we have three complete sets of independent observations made in three days...each set of observations were obtained in ten minutes...We present here the measurements made on March 9 of 2006." :wink:

    And here's a direct quote from page 3: "An random choice for the light beam direction, as in experiment mounted on rotating table, can easily lead to ambiguous results." :rolleyes:

    And here, from page 5 (emphasis mine): "These experimental results contradict the so-called Lorentz's theorem[18], which states that the course of the relative rays is not affected by the motion of the Earth if quantities of the second order are neglected..." :rofl:

    "Now, after our experimental results, that certainly will be confirmed by other similar experiments, we conclude that the course of the rays is affected by the motion of the Earth, and a predominant quantity of first order describes well the experimental results." :eek:

    We'll, perhaps...if you count the active slewing of your (or your sister's employer's?) telescope wrt the horizontal plane as "the motion of the Earth" and the Earth's gravity deflecting your taped-down laser pointer as this "predominant quantity of first order".

    You're actually trying to square these guy's "result" with SR, aren't you? Care to cite a reference for this? :uhh:
    Last edited: Apr 10, 2006
  5. Apr 10, 2006 #4
    I really couldn't follow your post. Too many funnies , too many words and no math.
    So, before you put words in my mouth, let me explain again, the reference curve (horizontal line) that they use for SR is wrong. It has been proven wrong by a series of experiments by the foremost experts in testing Lorentz violations (this is the group formed by Achim Peters, Braxmaier, etc). See here:


    And, BTW, they are also experts in testing one way light speed isotropy.
    Last edited: Apr 10, 2006
  6. Apr 10, 2006 #5


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    Please cite a specific credible reference explaining more about this measurable first order "sine wave caused by the diurnal variation of the lab speed" and apply it against the specific claims made within this Navia et al. paper.
    Last edited: Apr 10, 2006
  7. Apr 10, 2006 #6

    What do you mean by "credible"? This people are THE number one in the field.
    Why don't you read their web page , they make clear reference to this issue (look under Kennedy Thorndike) and to the papers where they analyze the effect.

    Let's also add this one to the ever growing list of test of one way light speed isotropy:

    2005: S. Herrmann, A. Senger, E. Kovalchuk, H. Müller, A. Peters: "Test of the isotropy of the speed of light using a continuously rotating optical resonator", Phys. Rev. Lett. 95, 150401 (2005).
    Last edited: Apr 10, 2006
  8. Apr 10, 2006 #7


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    I mean a specific published reference that we can discuss, that's all.

    I bet they don't make any reference to anything like this at all. You do realize that the Navia et al. paper claims to have detected a first-order effect based only on ten-minutes worth of observational data, right? And that you seem to actually be claiming that the paper you're citing will explain this claim made by Navia et al. as a natural consequence of SR?

    Are you as sure about this as you are about everything else?
  9. Apr 10, 2006 #8
    I am not here to take bets. If you have something to say, back it up.

    I am getting the impression that :

    a. you are talking down to me
    b. you are trying to intimate that I am backing up the Navia paper - this is the farthest from the truth, I think that the Navia paper is patently wrong and that it will not be published (unless there is some miracle).
    I offered my opinion as to what is wrong with it. The SR curve is wrong , this is a fact. For the rest, please speculate on your own, not on my account.

    Yes, I am as sure as the fact that you bungled the calculation of the phase differential on the Gagnon experiment. I found your mistakes multiple times, the latest one on the phase differential is the most obvious. I decided to let you think about it for a few days, maybe you will find it. If not, ask a specialist in wave theory.
    Last edited: Apr 10, 2006
  10. Apr 10, 2006 #9


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    I looked at the first paragraph on the Kennedy-Thorndike experiment that is posted at the website you cited. It has no bearing whatsoever on any of the claims made within the Navia et al. paper. The experiment described in Navia et al. ran for all of ten minutes and they effectively claim to have actually measured a first-order violation of the rotational invariance component of local Lorentz symmetry. The Kennedy-Thorndike experiment described on the website that you cited is a completely different test of the boost invariance component of local Lorentz symmetry.

    "This comparison has been done for about 190 days. During this time the velocity of the laboratory changes due to Earth's orbital motion around the sun. A velocity dependence of the speed of light, which would mean a non-vanishing RMS-parameter A would manifest itself in a sinusoidal variation of the measured difference frequency at the period of one year. " -- http://qom.physik.hu-berlin.de/

    I thought that you would see your enormous mistake and laugh along with me, but since that's not the case I apologize.

    No, I'm saying that there really is something (more than one thing) terribly wrong with the Navia et al. paper, but you don't seem to notice any of that and your off complaining about some relatively tiny K-T effect that doesn't have anything whatsoever to do with the claims made in the Navia et al. paper.

    This is not a fact. The flat SR curve in Fig. 6 of the Navia paper is one of the few things within their paper that looks perfectly reasonable to me.
    Last edited: Apr 10, 2006
  11. Apr 11, 2006 #10
    I was going to explain it to you, mathematically but seeing your post , I decided against it. The experiments are different but the mathematical explanation of the effect is the same. There is no point trying to tell you anything, you already know everything . Have fun.
    Last edited: Apr 11, 2006
  12. Apr 11, 2006 #11
    The link comes up “page not found”. So I used
    http://arxiv.org/PS_cache/astro-ph/pdf/0604/0604145.pdf [Broken]

    These findings do not surprise me as there have been many one-way experiments indicating anisotropy in the speed of light in the order of 370Km/s: -

    1991 DeWitte’s experiment (a one-way electrical pulse experiment).

    1990, Krisher et al performed a one-way light experiment that reported a negative result, but could not rule out an ether flow that is at rest with respect to the CMBR.

    1988, Gagnon, Torr, Kolen and Chang, published the results of their experiment "Guided-wave measurement of the one-way speed of light", which reported, "Our results have not yielded a measurable direction-dependent variation of the one-way speed of light. A clear null result is obtained for a hypothesis in which anisotropy of the CMBR is used to define a preferred reference frame". And Harold Aspden's considers their work important, as their experimental data clearly shows an eastward motion effect. And so it is possible to sense the speed of a test device using optical speed-of-light sensing wholly confined within the enclosure housing the apparatus.

    In 1986, E W Silvertooth claimed to have measured the 378 km/s cosmic motion using an optical sensor that measures the spacing between standing wave nodes. Although the experiment has not been confirmed, their results agree with recent findings.

    1933 Dayton Miller's ether drift experiments (similar to Michelson-Morley type experiments but more sensitive). A review of his work by James DeMeo shows indisputable evidence that data collected by Miller was affected by the sidereal period and this is clear proof of a cosmological ether drift effect.

    Their experiment is professional and I support their findings, but I don’t agree with Ether Gauge Theory that they use in their analysis, nevertheless it a step forward.
    Last edited by a moderator: May 2, 2017
  13. Apr 11, 2006 #12
    Actually they did not.

    Unpublished due to the fact that it was not reproducible. Well known as a crackpot .

    The summary says it all: no anisotropy. Invalidates "aether" theory.

    The summary says it all: no anisotropy. Invalidates "aether" theory.

    Refuted as unreproducible, the effect has been proven to be due to experimental error.

    Explained recently by the group of experimenters at the University of Berlin. Dayton Miller (and Maurice Allais after him) missed the fact that the lab (and interferometer) speed have a sine wave function.

    The same researchers published a new experiment in 2005 (see below). Result: aether theory is refuted again.

    2005: S. Herrmann, A. Senger, E. Kovalchuk, H. Müller, A. Peters: "Test of the isotropy of the speed of light using a continuously rotating optical resonator", Phys. Rev. Lett. 95, 150401 (2005).
    Last edited by a moderator: May 2, 2017
  14. Apr 11, 2006 #13
    No argument with that, EGT is pure garbage, written by another crank:

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