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Topic: SPECIAL RELATIVITY INCOMPATIBLE WITH DOPPLER EFFECT
Replies: 4   Last Post: Sep 26, 2013 12:58 AM

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 Pentcho Valev Posts: 2,853 Registered: 12/13/04
Re: SPECIAL RELATIVITY INCOMPATIBLE WITH DOPPLER EFFECT
Posted: Sep 26, 2013 12:58 AM

http://www.cmmp.ucl.ac.uk/~ahh/teaching/1B24n/lect19.pdf
Tony Harker, University College London: "The Doppler Effect: Moving sources and receivers. The phenomena which occur when a source of sound is in motion are well known. The example which is usually cited is the change in pitch of the engine of a moving vehicle as it approaches. In our treatment we shall not specify the type of wave motion involved, and our results will be applicable to sound or to light. (...) Now suppose that the observer is moving with a velocity Vo away from the source. (....) If the observer moves with a speed Vo away from the source (...), then in a time t the number of waves which reach the observer are those in a distance (c-Vo)t, so the number of waves observed is (c-Vo)t/lambda, giving an observed frequency f'=f(1-Vo/c) when the observer is moving away from the source at a speed Vo."

If "in a time t the number of waves which reach the observer are those in a distance (c-Vo)t", then the speed of the light waves relative to the observer is:

c' = ((c - Vo)t)/t = c - Vo

in violation of special relativity. The relativistic corrections do not change essentially this conclusion - c' remains different from c. If Vo is small enough, the relativistic corrections are negligible and both f'=f(1-Vo/c) and c'=c-Vo are virtually exact formulas.

Pentcho Valev

Date Subject Author
9/17/13 Pentcho Valev
9/20/13 Pentcho Valev
9/22/13 Pentcho Valev
9/25/13 Pentcho Valev
9/26/13 Pentcho Valev