CORRECT ANALYSIS OF THE SAGNAC EFFECT

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#5973

From: Pentcho Valev
Date: Thu, 20 Dec 2007 09:11

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In discussing the Sagnac effect, both relativists and anti-relativists
make the following mistake:

http://www.mathpages.com/rr/s2-07/2-07.htm
"Quantitatively, if we let w denote the angular speed of the loop,
then the circumferential tangent speed of the end point is v = wR, and
the sum of the speeds of the wave front and the receiver at the "end"
point is c-v in the co-rotating direction and c+v in the counter-
rotating direction.....This analysis is perfectly valid in both the
classical and the relativistic contexts."

The values c-v and c+v above are "perfectly valid" only in the
relativistic context. If by "classical" the author means "Newtonian",
the analysis is by no means "perfectly valid". According to an
observer at rest, in the classical context, the speed of light is c+v
in the co-rotating direction and c-v in the counter-rotating direction
so the correct text would be:

"Quantitatively, if we let w denote the angular speed of the loop,
then the circumferential tangent speed of the end point is v = wR, and
the sum of the speeds of the wave front and the receiver at the "end"
point is c in the co-rotating direction and c in the counter-rotating
direction."

Pentcho Valev
pvalev@yahoo.com

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From: Pentcho Valev <pvalev@yahoo.com>
Newsgroups: sci.physics.relativity, sci.physics, sci.astro, fr.sci.physique, 
 fr.sci.maths
Subject: CORRECT ANALYSIS OF THE SAGNAC EFFECT
Date: Thu, 20 Dec 2007 01:11:39 -0800 (PST)
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