In popular and educational books on the theory of relativity, it is frequently claimed that Michelson and Morley experimentally proved the fallacy of the ethereal concept. This is an untrue statement. The outcome of the Michelson-Morley experiment demonstrated the impossibility of detecting ether using an experiment of this type, but not the absence of ether. One must not lose sight of the fact that the results of the Michelson and Morley experiment did not prevent the notions about the ether from be ing retained for a good two decades after they obtained their negative measurement result. Michelson himself and Lorentz shared these notions. ndeed, FitzGerald and Lorentz explained this result by way of the longitudinal shortening of objects moving through the ether, i.e., they explained it within the fram ework of the ethereal world view. And so it was that in the waning years of his life, in 1952, Einstein wrote in the article “Relativity and the Problem of Space”: Concerning the experiment of Michelson and Morley, H. A. Lorentz showed that the result obtained at least does not contradict the theory of an ether at rest” .Yes, von Laue wrote that in 1914, so it is old news.
In this regard, the remark of a proponent and popularizer of the theory of relativity, M. von Laue, should also be clear, who wrote: “…it was experimentally impossible to make a choice between this theory (the Lorentz theory) and Einstein’s theory of relativity, and if the Lorentz theory nonetheless took a back seat – even though it still has proponents among physicists – this then undoubtedly occurred due to reasons of a philosophical nature” .
Today, relativity is usually taught as being inspired by the Michelson–Morley experiment. The Lorentz electron theory was invented to explain the experiment. Einstein denied that the experiment was of any importance to him, because Lorentz had already used to relativity to explain it.