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Topic: EINSTEINIANA : THE ULTIMATE-SPEED-LIMIT RED HERRING
Replies: 4   Last Post: Aug 1, 2013 4:56 PM

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 Dr J R Stockton Posts: 10 Registered: 4/28/13
Re: EINSTEINIANA : THE ULTIMATE-SPEED-LIMIT RED HERRING
Posted: Aug 1, 2013 4:56 PM

In sci.math message <earle.jones-0C430F.16163430072013@news.giganews.com
>, Tue, 30 Jul 2013 16:16:34, Earle Jones <earle.jones@comcast.net>
posted:

>
>The permittivity and permeability of a vacuum are well known. These are
>constants. Therefore c (speed of light in a vacuum) is a constant.
>

Incorrect. The speed of light, in metres per second, is constant by
definition, and it is that definition which determines the length of a

The speed of light is 299 792 458 metres per second. The permeability
of vacuum is, by definition, 4 pi 10^-7 henries per metre. The
permittivity of vacuum is therefore, from the formula given earlier,
8.854 187 817 ... 10^-12 farads per metre.

--
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Web <http://www.merlyn.demon.co.uk/> - FAQish topics, acronyms, and links.
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Date Subject Author
7/30/13 Pentcho Valev
7/30/13 Earle Jones
7/31/13 Pentcho Valev
7/31/13 Pentcho Valev
8/1/13 Dr J R Stockton