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Topic: Einstein's Light Postulate: the Beginning and the End of Modern Physics
Replies: 4   Last Post: Oct 5, 2017 4:46 AM

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Pentcho Valev

Posts: 5,908
Registered: 12/13/04
Re: Einstein's Light Postulate: the Beginning and the End of Modern Physics
Posted: Oct 4, 2017 3:02 AM
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The observer starts moving towards the light source. The wavecrests start hitting him more frequently - the frequency he measures increases - which means that the speed of the wavecrests relative to the observer increases as well, in violation of Einstein's relativity:

"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." https://www.youtube.com/watch?v=bg7O4rtlwEE

"Let's say you, the observer, now move toward the source with velocity Vo. You encounter more waves per unit time than you did before. Relative to you, the waves travel at a higher speed: V' = V+Vo. The frequency of the waves you detect is higher, and is given by: f' = V'/L = (V+Vo)/L."
http://physics.bu.edu/~redner/211-sp06/class19/class19_doppler.html

"Vo is the velocity of an observer moving towards the source. This velocity is independent of the motion of the source. Hence, the velocity of waves relative to the observer is c + Vo. [...] The motion of an observer does not alter the wavelength. The increase in frequency is a result of the observer encountering more wavelengths in a given time." http://a-levelphysicstutor.com/wav-doppler.php

Pentcho Valev



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