Thursday, June 3, 2021

Einstein book addendum

I wrote an Einstein book several years ago. One of the main arguments was that Einstein does not deserve credit for discovering relativity. The reasons are:

1. All of the important special relativity equations were published by others before Einstein wrote anything on the subject.

2. Einstein's 1905 theory was not seen at the time as being particularly novel or influential.

3. The main concept behind relativity is that spacetime has a non-euclidean geometry. This was published by others, and missed by Einstein.

Historians acknowledge (1), but credit Einstein for some non-mathematical subtlety such as accepting local time, saying the aether was superfluous, or giving a derivation that was not ad hoc. The trouble with these is that what Einstein actually said about local time and the aether was nearly identical to what Lorentz and Poincare said years earlier.

Item (2) is also acknowledged, but not so well known. There were papers written on competing theories, and they referred to the "Lorentz-Einstein theory", as if there were no distinction between the Lorentz and Einstein theories. Einstein tried, but was never able to give a good explanation as to how his theory differed from Lorentz's. Lorentz said that Einstein merely postulated what he and others had deduced from previous theory and experiment. Poincare and Minkowski did explain how their versions of relativity differed from Lorentz.

As for (3), it is well-known that Minkowski published a non-euclidean geometry treatment of relativity, and that is what caught on with physicists and led to widespread acceptance. Einstein complained that he turned the theory into something that he could not recognize. Some assume that Minkowski built on Einstein's ideas, but Lorentz and Poincare were much greater influences, and it is not clear that Minkowski got anything from Einstein.

Even as late as 1910, when someone suggested that Einstein's non-Euclidean geometrical view could avoid a paradox of Lorentzian relativity, Einstein wrote a letter to the journal denying that he has any such view different from Lorentz's. That would have been a great opportunity for Einstein to take credit for a conceptual advance, but he denied it.

In short, here is the paradox. If the Lorentz contraction is applied to a spinning bicycle wheel, the tire contracts while the spoke lengths remain the same. This seem to contradict the Euclidean geometry fact that a circle circumference is 2π times the radius. Adopting a non-euclidean geometry resolves the paradox.

Someone similar happened in the 1920s, when a general relativity explained that non-euclidean geometry was the heart of the theory. Einstein published a favorable book review, but denied the geometry view.

See also: Einstein did not discover relativity, Einstein book update, and Second Einstein book update

The history of relativity gives the background for the distortions in Physics that came later in the book. Einstein found that he was widely idolized for his supposed genius ability to do non-empirical theorizing. By the late 1920s, he was repudiating his earlier more empirical approach. Dutch physicist Jeroen van Dongen has written a very good new paper on this XX century trend towards non-empirical Physics. He writes:

In the absence of the empirical, Einstein emphasized the merit of his personal epistemological conviction, along with its success as documented in his version of his biography: the epistemic benefit of doing unified field theory was bound up with the virtuous dispositions of his kind of theorist.
This is a polite way of saying that Einstein lied about his life story in order to promote himself and the virtues of his worthless unified field theory research.
For admiration of Einstein as empiricist icon, see e.g. Heisenberg (1989) ; Heisenberg here further recalls his surprise when Einstein explained to him in 1926 that he no longer held empiricist views. In 1927, Heisenberg signaled a difference of opinion regarding the role of `simplicity' and the empirical with Einstein (Heisenberg to Einstein, 10 June 1927, cited on p. 467 in Pais 1982); Einstein himself was well aware of his isolation and the negative judgment of his peers; see Pais (1982), p. 462. See Howard (1994) on the logical empiricists. ...

Dismissal could take a moral tone, for instance when Robert Oppenheimer deemed that Einstein had been "wasting his time." In fact, he had gone "completely cuckoo", Oppenheimer added in private, or, as he put it in public, Einstein had "lost contact with the profession of physics." Clearly, the Einstein of unified field theory was not a proper theorist.

That's right. Respect for Einstein early was based on empirical work. The Nobel Prize was for one his more empirical papers. Then Einstein went non-empirical, and his work was cuckoo.

But a philosophical shift made the non-empirical work more respectable than the empirical. Those logical empiricists were driven out pf academia. The Kuhn paradigm shifters put non-empirical work as the true scientific revolutions that everyone admired.

Example of Einstein against empiricism:

In the same letter, Einstein expressed that he was no longer thinking about experiments on the wave and particle properties of light, and that one "will never arrive at a sensible theory in an inductive manner", even if "fundamental experiments" could still be of value - once again deprecating the quantum program's empirical slant.
The history is imprtant because these Kuhnian revolutions never happen. The discoveries of relativity and quantum mechanics in the early XX century were driven by empirical findings.

The patron saints of non-empirical philosphy are Copernicus, Galileo, Einstein, and Kuhn.

The example of Copernicus is particularly apt for today’s discussion. Copernicus proposed his alternative to the fairly successful Ptolemean universe in 1543. Yet, this theoretical proposal was basically beyond any meaningful notion of empirical falsifiability. This situation persisted pretty much until Galileo pointed the newly invented telescope to the heavens and in 1610 observed the phases of Venus.
The phases of Venus were not decisive, and arguments for and against continued until Isaac Newton. Some of the arguments were not fully resolved for centuries.

Kuhn makes a big deal out of this because Copernicus described a "revolution" of the Earth around the Sun, and the theory eventually caught on even tho there was little empirical evidence for it at the time. So he portrayed scientists as a bunch of irrational fad-followers.

In the case of relativity, all of the important early papers referred directly to the Michelson-Morley experiment as the crucial experiment, as well as to other experiments. This was acknowledged by everyone at the time, including Einstein. The view only got revised later, in efforts to credit Einstein and devalue empiricism.

I have posted here many times that I think that the theories of relativity and quantum mechanics could have been anticipated by clever theorists. If you are looking for a locally causal field theory, the math leads directly to relativity and gauge theory. In a way, that is what Maxwell did with electromagnetism.

And once you accept that we needed a wave theory of matter, quantum mechanics is the obvious thing. Nobody knows any better way to even propose such a theory. So these theories could have been developed from pure theory.

Or so it seems in retrospect. It never happened that way.

String theorists would like to tell you that Einstein created relativity out of pure theory, and that inspired string theorists to do the same today. Forget it. When Einstein shifted to purely theory analysis, his work was garbage.

Peter Woit mentions the above paper, and a comment notes that it ends by saying that non-empirical physics like string theory is a Kuhnian paradigm shift, and urging that we “keep funding it as generously as before.”

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