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Einstein's relativistic Doppler formula

Pierseaux Yves
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Abstract

We note that Einstein's relativistic Doppler formula presents a strange aspect. For incident light received under a fixed non zero angle, the Doppler shift will change from blueshift to redshift (or vice-versa) for some critical relative velocity of the observer and the source.

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Pierseaux Yves. 2005-09-20. Einstein's relativistic Doppler formula. https://arxiv.org/abs/physics/0509163

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