If as a result of the equivalence principle we can derive the gravitational red shift entirely from the perspective of an accelerating body with no reference to gravity and no reference to gravitational time dilation then one is essentially just working out the Doppler shift of a signal associated with an accelerating body. This of course is the essence of the equivalence principle, the fact that you can work out the equation for gravitational red shift from a situation without gravity.(adsbygoogle = window.adsbygoogle || []).push({});

As gravitational time dilation is associated with gravitational redshift, it is also assumed to be associated with an inertially accelerated body. This is a consequence of the equivalence principle.

I assume that the equivalence principle implies that an inertially accelerated body will experience time dilation. Time flow will be greater towards the front and less to the rear.

But if the Doppler shift can account entirely for the frequency of light that is measured in an inertial situation, it is as if the time dilation is having no effect at all.

If there is time dilation in an inertial situation (accelerating) then surely it has to have an effect on the wavelength measured beyond the calculated Doppler shift.

In a gravitational context, time dilation causes the red shift.

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# Gravitational time dilation, redshift and doppler

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