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

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Discussion Overview

The discussion revolves around the validity of D.Y. Gezari's paper regarding the speed of light, specifically addressing claims of variable speed based on lunar ranging evidence. Participants examine the paper's methodology, conclusions, and overall credibility, engaging in a critical analysis of its claims and implications.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant argues that the calculations presented in the paper yield a speed of light that differs by at most 1 m/s from the canonical value, challenging the author's claim of a 200 m/s difference.
  • Another participant suggests that the conclusion drawn by the original poster seems more plausible than the author's claim, referencing an external article for support.
  • Concerns are raised about the paper's failure to pass peer review, with one participant asserting that the methodology is fundamentally flawed due to the misuse of special relativity across different frames.
  • It is noted that the speed of light is defined as exactly 299792458 m/s in SI units, implying that any deviation from this is incorrect by definition.
  • Critiques of the paper's quality include claims of unsupported assertions regarding time of flight measurements and the impossibility of determining two unknowns from a single measurement, as well as a typographical error in the acknowledgments.
  • One participant questions the appropriateness of discussing the paper on the forum, labeling it as remarkably poor and suggesting that it should not have been submitted for publication in its current form.

Areas of Agreement / Disagreement

Participants express disagreement regarding the validity of Gezari's claims, with multiple competing views on the paper's credibility and the implications of its findings. There is no consensus on the paper's conclusions or its methodological soundness.

Contextual Notes

Participants highlight limitations in the paper's claims, including unsupported assertions and potential misuse of special relativity. The discussion reflects ongoing uncertainty about the paper's validity and the implications of its findings.

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Daniel.Y.Gezari @ nasa.gov 's paper

arxiv.org/vc/arxiv/papers/0912/0912.3934v1.pdf
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
DBL/TLB, DBR/TBL, and (DBL+DBR)/(TLB +TBR).
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?
 
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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.
 
Any claim that c in SI units is anything other than exactly 299792458 m/s is clearly wrong by definition.
 
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mfb said:
The preprint has been submitted to a journal in 2009, but apparently failed peer review.

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 acknowledgments, which demonstrates how sloppy he is.

This is why this thread should be closed.
 
The paper referenced in the OP is not a reputable source. Thread closed.
 
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