🚀 go-pugleaf

Dear JanPB:

"JanPB" <filmart@gmail.com> wrote in message 
news:1189963511.109963.323880@d55g2000hsg.googlegroups.com...
> On Sep 16, 7:00 am, Pentcho Valev <pva...@yahoo.com> wrote:
>
> [snip idiocies]
>
>> http://arxiv.org/PS_cache/gr-qc/pdf/9909/9909081v7.pdf
>> Vesselin Petkov: "One of the fundamental facts of
>> modern physics is the constancy of the speed of light.
>> Einstein regarded it as one of the two postulates on
>> which special relativity is based. So far, however, little
>> attention has been paid to the status of this postulate
>> when teaching special relativity. It turns out that the
>> constancy of the speed of light is a direct consequence
>> of the relativity principle, not an independent postulate.
>
> This doesn't seem right. The speed of light constancy
> doesn't automatically follow from the first postulate
> unless one adds the extra assumption of no aether.
> The first postulate alone is not enough as one could
> obviously set up a theory with aether, the first
> postulate, and Maxwell's equations, all together in a
> happy (logical but not physical) family.
>
> This happy family would not be SR and would not
> match experimental results but its very existence
> as a possible logical corollary disproves Petkov's
> claim. Comments?

The constancy of the speed of light follows from Maxwell, Maxwell 
formulated his "laws of physics" with an aether, and the aether 
"fell out" in the derivation.  So if Maxwell's relations qualify 
as laws of physics under postulate 1, then postulate 2 is 
superfluous.

David A. Smith