In 1887 the Michelson-Morley experiment directly proved Newton's variable speed of light. In 1921 Einstein, already a deity, declared that the experiment had proved constant speed of light, and the blatant lie has been universally taught ever since (post-truth science):

The New York Times, April 19, 1921: "The special relativity arose from the question of whether light had an invariable velocity in free space, he [Einstein] said. The velocity of light could only be measured relative to a body or a co-ordinate system. He sketched a co-ordinate system K to which light had a velocity C. Whether the system was in motion or not was the fundamental principle. This has been developed through the researches of Maxwell and Lorentz, the principle of the constancy of the velocity of light having been based on many of their experiments. But did it hold for only one system? he asked. He gave the example of a street and a vehicle moving on that street. If the velocity of light was C for the street was it also C for the vehicle? If a second co-ordinate system K was introduced, moving with the velocity V, did light have the velocity of C here? When the light traveled the system moved with it, so it would appear that light moved slower and the principle apparently did not hold. Many famous experiments had been made on this point. Michelson showed that relative to the moving co-ordinate system K1, the light traveled with the same velocity as relative to K, which is contrary to the above observation. How could this be reconciled? Professor Einstein asked." http://query.nytimes.com/gst/abstrac...66838A 639EDE

Banesh Hoffmann, Einstein's collaborator, admits that, originally ("without recourse to contracting lengths, local time, or Lorentz transformations"), the Michelson-Morley experiment directly proved Newton's variable speed of light and disproved the constant speed of light:

"Moreover, if light consists of particles, as Einstein had suggested in his paper submitted just thirteen weeks before this one, the second principle seems absurd: A stone thrown from a speeding train can do far more damage than one thrown from a train at rest; the speed of the particle is not independent of the motion of the object emitting it. And if we take light to consist of particles and assume that these particles obey Newton's laws, they will conform to Newtonian relativity and thus automatically account for the null result of the Michelson-Morley experiment without recourse to contracting lengths, local time, or Lorentz transformations. Yet, as we have seen, Einstein resisted the temptation to account for the null result in terms of particles of light and simple, familiar Newtonian ideas, and introduced as his second postulate something that was more or less obvious when thought of in terms of waves in an ether." Banesh Hoffmann, Relativity and Its Roots, p.92 https://www.amazon.com/Relativity-It.../dp/0486406768

Wikipedia tells the truth about the Michelson-Morley experiment here (elsewhere it says the opposite):

"Emission theory, also called emitter theory or ballistic theory of light, was a competing theory for the special theory of relativity, explaining the results of the Michelson–Morley experiment of 1887. [...] The name most often associated with emission theory is Isaac Newton. In his corpuscular theory Newton visualized light "corpuscles" being thrown off from hot bodies at a nominal speed of c with respect to the emitting object, and obeying the usual laws of Newtonian mechanics, and we then expect light to be moving towards us with a speed that is offset by the speed of the distant emitter (c ± v)." https://en.wikipedia.org/wiki/Emission_theory

Even John Norton, high priest in the Einstein cult, tells the truth about the Michelson-Morley experiment:

John Norton: "The Michelson-Morley experiment is fully compatible with an emission theory of light that CONTRADICTS THE LIGHT POSTULATE." http://philsci-archive.pitt.edu/1743/2/Norton.pdf

That is, originally (prior to FitzGerald and Lorentz introducing, ad hoc, contracting lengths), the Michelson-Morley experiment directly proved Newton's variable speed of light and disproved the constant (independent of the motion of the emitter) speed of light posited by the theory of the nonexistent ether and "borrowed" by Einstein in 1905:

Albert Einstein: "I introduced the principle of the constancy of the velocity of light, which I borrowed from H. A. Lorentz's theory of the stationary luminiferous ether..." https://en.wikipedia.org/wiki/Lorentz_ether_theory

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