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Mass change caused by the Doppler shift for light.

This short article explains how relativistic transformations can be replaced by the Doppler
effect when it affects mass.

The simplest formulation of relativistic mass and the Einstein invariance is

m0 = m sqrt(1 – v2/c2)

, where m0 is the rest-mass. The remainder of the Doppler effect for light affecting mass is

mS = m0 sqrt[(1 – v/c)/(1 + v/c)]

, where mS is the source-mass. These two equations together are the same as the full Doppler
effect for light affecting mass (causing mass change), namely

mS = m(1 – v/c)

, where the source-mass takes on the traditional place of the rest-mass. The resulting kinetic
energy is

KE = mc2 – mSc2 = pc

, where p is the impulse p = mv.

1 May 2012, Oegstgeest
Brouwer, P.J.

About PJB1979

Pieter Brouwer has written 10 post in this blog.