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What is wrong in D.Y. Gezari's paper about speed of light?

  1. May 9, 2015 #1
    Daniel.Y.Gezari @ nasa.gov 's paper

    lunar ranging evidence of variable c

    fig 2 of this paper shows DLB as the distance between the observatory (Launch) and the retro-reflector at the moment of the Bounce, DBR as the distance between retro-reflector (at the moment of the Bounce) and the observatory,
    In my opinion the speed of light with respect to the observatory is
    With the appropriate data in Table I this gives a c0 which differs at the most 1m/s from the canonical value c.
    So, the claim that the "measured" c differs 200m /s with the canonical c is invalid

    Can anyone agree?
  2. jcsd
  3. May 9, 2015 #2


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  4. May 9, 2015 #3


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    The preprint has been submitted to a journal in 2009, but apparently failed peer review. For a good reason, as the refutation shows.

    The whole idea was doomed to fail anyway. You cannot use special relativity in one frame to calculate what would happen in another frame, and then "find" a violation of special relativity. It has been shown that the transformations of special relativity are self-consistent.
  5. May 9, 2015 #4


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    Any claim that c in SI units is anything other than exactly 299792458 m/s is clearly wrong by definition.
  6. May 9, 2015 #5

    Vanadium 50

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    So should we be discussing it on PF?

    This paper is remarkably poor. I would not let one of my grad students or postdocs send it to a journal without revision. The paper claims on page 2 "The measured time of flight of individual laser pulses varies by as much as ~3 sec." This is completely unsupported by the rest of the paper. Second, it is conceptually impossible to make one measurement (time of flight) and determine two unknown quantities (lunar distance and speed of light). Finally, he misspells Jennifer Wiseman's name in the acknowledgements, which demonstrates how sloppy he is.

    This is why this thread should be closed.
  7. May 9, 2015 #6


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    The paper referenced in the OP is not a reputable source. Thread closed.
    Last edited: May 9, 2015
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