As a simple example, there are many claims that Lorentz and Poincare clung to a stationary aether, while Einstein abolished it. It is much more accurate to say that Lorentz and Einstein had the same beliefs about the aether, and Poincare abolished it.
Lorentz's 1895 paper says, after a discussion of previous aether theories:
It is not my intention to enter into such speculations more closely, or to express assumptions about the nature of the aether. I only wish to keep me as free as possible from preconceived opinions about that substance, and I won't, for example, attribute to it the properties of ordinary liquids and gases. ...Einstein's 1905 paper only says this about the aether:
That we cannot speak about an absolute rest of the aether, is self-evident; this expression would not even make sense. When I say for the sake of brevity, that the aether would be at rest, then this only means that one part of this medium does not move against the other one and that all perceptible motions are relative motions of the celestial bodies in relation to the aether.
The introduction of a “luminiferous ether” will prove to be superfluous inasmuch as the view here to be developed will not require an “absolutely stationary space” provided with special properties, nor assign a velocity-vector to a point of the empty space in which electromagnetic processes take place.So Lorentz said that he was not expressing assumptions about the aether, and Einstein said that the introduction of aether was superfluous to his presentation. Lorentz said that the absolute rest of the aether makes no sense, and Einstein said that absolutely stationary space was not required.
In the three years after 1905, there is no record of Lorentz or Einstein expressing any disagreement about the aether, or of anyone else finding any such difference. Their theory was called Lorentz-Einstein theory. After 1908, the Poincare-Minkowski spacetime approach became popular, and the Lorentz-Einstein theory was obsolete.
Poincare wrote:
Whether the ether exists or not matters little - let us leave that to the metaphysicians; what is essential for us is, that everything happens as if it existed, and that this hypothesis is found to be suitable for the explanation of phenomena. ... while some day, no doubt, the ether will be thrown aside as useless. [1889]It is very strange that anyone would attach such great importance to the aether, when it played no part in Poincare's theory.
There is no absolute space, and we only conceive of relative motion; and yet in most cases mechanical facts are enunciated as if there is an absolute space to which they can be referred. 2. There is no absolute time. When we say that two periods are equal, the statement has no meaning, and can only acquire a meaning by a convention. [1901]
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