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Topic: WHY EINSTEIN PROPOSED HIS SECOND POSTULATE
Replies: 2   Last Post: Apr 26, 2014 4:54 AM

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 Pentcho Valev Posts: 6,212 Registered: 12/13/04
Re: WHY EINSTEIN PROPOSED HIS SECOND POSTULATE
Posted: Apr 26, 2014 4:54 AM

The assumption that the speed of light (relative to the observer) is independent of the speed of the light source is false but still can be justified in terms of light waves propagating in the ether. In contrast, the conclusion (derivable from Einstein's 1905 two postulates) that the speed of light (relative to the observer) is independent of the speed of the observer is unjustifiable. Any serious interpretation of the Doppler effect (moving observer) refutes both this conclusion and special relativity as a whole:

"Doppler effect - when an observer moves towards a stationary source. ...the velocity of the wave relative to the observer is faster than that when it is still."

"Doppler effect - when an observer moves away from a stationary source. ...the velocity of the wave relative to the observer is slower than that when it is still."

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."

Tony Harker: "In a time t the number of waves which reach the observer are those in a distance (c-Vo)t."

Consequence: The speed of the light waves relative to the moving observer is:

c' = distance/time = (c - Vo)t/t = c - Vo,

in violation of special relativity.

http://www.einstein-online.info/spotlights/doppler
Albert Einstein Institute: "The frequency of a wave-like signal - such as sound or light - depends on the movement of the sender and of the receiver. This is known as the Doppler effect. (...) Here is an animation of the receiver moving towards the source: (...) By observing the two indicator lights, you can see for yourself that, once more, there is a blue-shift - the pulse frequency measured at the receiver is somewhat higher than the frequency with which the pulses are sent out. This time, the distances between subsequent pulses are not affected, but still there is a frequency shift: As the receiver moves towards each pulse, the time until pulse and receiver meet up is shortened. In this particular animation, which has the receiver moving towards the source at one third the speed of the pulses themselves, four pulses are received in the time it takes the source to emit three pulses."

Let "the distance between subsequent pulses" be 300000 km. Then the frequency measured by the stationary receiver is f = 1 s^(-1) and that measured by the moving receiver is f' = 4/3 s^(-1). Accordingly, the speed of the pulses relative to the moving receiver is:

c' = (4/3)c = 400000 km/s

in violation of special relativity.

The relativistic corrections change essentially nothing. The speed of the receiver is (1/3)c so gamma is 1.05. Accordingly, the corrected f' is (1.05)*(4/3) s^(-1) and the corrected c' is (1.05)*(400000) km/s. Special relativity remains violated.

Pentcho Valev

Date Subject Author
4/24/14 Pentcho Valev
4/25/14 Pentcho Valev
4/26/14 Pentcho Valev