Doppler effect (stationary light source, moving observer):

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

Two obvious facts in the above scenario:

(A) The speed and the frequency of the light pulses vary proportionally for the observer.

(B) The wavelength (distance between light pulses) remains constant.

(A) and (B), generalized over all possible scenarios, in the presence or absence of gravity, will become the basic principles of resurrected, Einstein-free physics.

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