The formula

(frequency) = (speed of light) / (wavelength)

allows two axiomatizations:

Axiom 1 (Einstein 1905): The speed of light is constant.

Axiom 2: The wavelength of light is constant (for a given emitter).

Axiom 1 killed fundamental physics (converted it into an insane ideology). Axiom 2 will resurrect it (hopefully).

It is easy to show that the wavelength of light remains constant

(A) when the observer starts moving towards the emitter.

(B) when the emitter starts moving towards the observer.

(C) when light falls in a gravitational field.

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