Re: Speed of light and relativity

From: Martin Hogbin (goatNOSPAM1_at_hogbin.org)
Date: 10/12/04 

Date: Tue, 12 Oct 2004 17:07:16 +0000 (UTC)

"greywolf42" <mingstb@marssim-ss.com> wrote in message news:gpzad.3285$pM5.1904@news.flashnewsgroups.com...
> "Martin Hogbin" <goatNOSPAM1@hogbin.org> wrote in message
> >
> > Better to say that it has never been measured to have
> > any value other than c (in a vacuum and an inertial frame
> > of course).
>
> LOL! If one measures the speed of light, then one is (by definition)
> measuring 'c'. But the values are never measured to be 'constant.' What
> explicit value are you using?

The value of c is well known. Can you name any experiment in
which light is measured to travel at any speed other than c _in a
vacuum and an inertial frame_.

>
> Light speed varies when moving from one medium to another. (Huygens,
> Fresnell)

This is not in a vacuum.

> Light speed varies when the media its in is accelerated (Fizeau)

This is not in a vacuum.

> Light speed varies in vacuum when moving around a rotating table (Sagnac.)

Not when measured in an inertial frame.

> Light speed varies in vacuum on Earth when moving around a *stationary*
> table (Michelson-Gale.)

The measurement does not take place in an inertial frame because
the Earth is rotating.

> Light speed varies when moving around the Earth (Allan, Weiss, and Ashby).

The measurement does not take place in an inertial frame.

> Light is actually faster west than east (Sagnac) and faster down than up
> (Einstein.)

This is not an inertial frame.

> Light speed varies in vacuum when it passes by anything gravitational
> (Shapiro time delay).

The measurement does not take place in an inertial frame.

Martin Hogbin

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