Lorentz, Poincare, Einstein, and the Genesis of the Theory of Special RelativityThis is a fair review of early relativity publications. I learned a few things. Especially some of the circumstantial evidence that Einstein had access to other relativity papers that he refused to cite.
Hector GiacominiThis work offers a historical reading of the genesis of special relativity by placing the contributions of Lorentz, Poincare, and Einstein within their scientific and editorial context. It highlights the importance of the German periodical Beiblatter zu den Annalen der Physik as a key channel for the dissemination of international scientific research. The perspective advanced here is that the true revolution did not lie in special relativity itself, but in Maxwell's electrodynamics. Special relativity thus appears as the necessary expression of a framework already transformed by the universality of the speed of light.
Einstein's explanation of originality does not make any sense:
Einstein defined his own contribution as having transformed Lorentz’s “local time” into the physical time of a moving inertial frame, thereby elevating a mathematical construction to the status of an empirical quantity. ...There were numerous inexplicable failures to acknowledge Poincare's work, by Einstein and others. However there were exceptions, so it is clear that Einstein, Minkowski, and others knew about his work.It should be recalled that if Lorentz’s time variable t′ in his 1904 paper were merely an auxiliary mathematical device without physical meaning, it would be impossible to explain the negative results of the Michelson–Morley experiments. Lorentz, moreover, explicitly stated in that work that clocks based on electromagnetic mechanisms in the moving system must run slower.
Einstein claimed to not know about Lorentz's crucial 1904 paper and Poincare's short 1905 paper, but circumstantial evidence implies he knew about both before submitting his own 1905 relativity paper. They were available in a library that Einstein used regularly, and they had generated a lot of attention.
Even if Einstein somehow missed these papers in June 1905, he certainly knew about them when he wrote review papers later. There can be no excuse for Einstein and others not crediting these papers.
In summary: for Poincaré, relativity is grounded in Maxwell’s theory; for Einstein, it is framed as a general kinematic structure, but in practice still bound to Maxwell’s electrodynamics since the limiting speed is taken from it. The two formulations are therefore logically equivalent, differing only in which statement is postulated and which is derived. ...Yes, I agree that the theories are logically equivalent, and that Maxwell should be considered an early founder of special relativity.One may argue that the true revolution was not special relativity itself, but rather the electrodynamics of Ampère, Faraday, and Maxwell. It was this framework that largely shaped twentieth-century physics. ...
Einstein consistently thought in terms of electrodynamics.
Some credit Einstein with elevating special relativity from electrodynamics to a spacetime theory, because he wrote a section on kinematics. However it is really Poincare who did that.
The above paper says Poincare's relativity is grounded in Maxwell theory, but Poincare's 1905 papers explicitly say that it is a spacetime theory, and apply it to gravity without any electromagnetism involved. In the Lorentz-Einstein theory, it is never clear whether the relativistic effects are purely electromagnetic.
By 1905, many German physicists were already referring to a “Lorentz–Einstein theory,” which probably prompted Einstein to restate explicitly his intellectual independence. ...By "late 1900s" he must mean 1905-10. The Lorentz-Einstein theory could have been considered just an interpretation of the Maxwell theory.These examples show that, by the late 1900s, the expression “Lorentz–Einstein” circulated across private correspondence (Planck), major physics journals (Bucherer, Levi-Civita), and popular scientific works (Cohn). Far from being marginal, it indicates that relativity was then widely perceived in Germany as a joint construction, or at least as a theory of shared intellectual parentage between Lorentz and Einstein. By contrast, Poincaré — though a central figure in the same debates — was already largely excluded from this emerging tradition.
The above paper does not explain why Poincare was excluded. The record is clear that everyone knew who he was and what he did. He was extremely highly respected. Maybe even the most respected and widely-read scholar in Europe. If someone thought that his work was substandard or inferior or derivative or wrong, he could have said so. No one did.
The paper notes that there is a paper trail showing how Lorentz and Poincare came to their conclusions about relativity, but Einstein's route is more mysterious. He cites no previous works. Some claim that Einstein was inspired in isolation. This paper makes it clear that Einstein had access to good libraries and read the top journals. He was plugged into current research.
If Einstein had some plausible story, that would be worth considering. But he did not. The obvious conclusion is that he got all those ideas from Lorentz and Poincare.
Referring to this paper and adding relatively very little bits from here and there...
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Lorentz, Poincare... Two giants.
And, it took even Lorentz some *nine* *years*, even *after* being prodded by none less than *Poincare*, to go from his 1895 equations:
x' = x − vt, t' = t - vx/c^2
to his 1904 equations:
x' = l(v) γ(x − vt), t' = l(v) γ ( t - vx/c^2 ) .
It must've been some time *before* his 1894 paper that Lorentz had arrived at the right parameter for hypothesizing the expansion in terms of powers; the parameter being: v/c. Lorentz himself identified the 1895 equation to be correct to the first order, and the 1904 equation to all orders (or at least made it so obvious that Gans himself could add this conclusion in his 1 page review later).
Poincare, despite prodding Lorentz for the mathematical and other short-comings, either didn't directly work on the problem for himself, or didn't propose competing equations for LT. He was a bit more conceptual or philosophical, writing and talking about operational definition of time, fields as carrying energy, a relational view of space, and hypothetical and provisional nature of scientific laws (1898 -- 1902). Especially contrast the last to Lorentz' years-long effort to keep the form of the ED laws the same in *different* frames --- at least the uniformly moving frames.
It was only after Lorentz got to the 1904 equation that Poincare could now wrinkle out the remaining minor incosistencies from Lorentz's work, find some more properties about LT, and weave out everything in reference to his relativity principle. He took about one year (or at least, several months).
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I wonder what all the hoops Lorentz had to go through, to get to the correct form of γ. Note not just l(v) but γ itself also is actually a *function* of v (even for inertial frames), although it does become a constant for a pre-specified v.
How many years the master that Lorentz was, took? May be eight years?
Also note, the correct expression for γ is weird --- its relation to the parameter of the expansion (viz., v/c) is rather indirect. You don't run into multiplying factors like that every day in the mathematical physics, do you? I mean to say, a mere coefficient of such a form is one thing; but a ``coefficient'' that has the expansion parameter in it is another thing. How many references to the various implications to which the ED laws lead, must've guided Lorentz? in the process of all attempts, before he got to the correct expression of γ?
And then, it took *Poincare's* wide vision, his overarching knowledge of maths, and his further work on this topic too, even just to show that l(v) had to be 1 for all v's. How much time did he take for all that work related to LT? At least a few months?
... continued
... continued from above...
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The Year of the Miracles:
PhD thesis is submitted soon after the new year arrives. ... Now begin the miracles.
A few months later:
Einstein's PE effect paper all but falls short of saying that the support of the photon is finite. He might have been inspired from the discrete bodies studied in classical mechanics, but such an assumption, never corrected by any one, would later go on to introduce more confusions of understanding and principle than the illumination of the PE effect (through the light as the quantum particles idea). Decades later, it would compel physicists to subtract infinities from infinities. [To be honest, this is not to cast any doubt about the genius of the explanation of the PE effect itself. But it must be mentioned. At least some time, some where.]
A few months later:
Einstein's Brownian motion paper is, speaking mathematically, quite confused. It's not at all what one would expect from a master of physics and maths. Whenever he introduces something new, all the equations he derives are all for the spatially discrete bodies (of finite support), and for finite speeds of propagation with finite momenta. But then, right in flow of the writing (without even a sub-section heading or so), he takes a sudden jump (unnoticed by all others, to the best of my knowledge), and declares that the error function based (i.e. Fourier modes based) solution still applies. In the process, he overlooks the fact that all such modes have support over the entire domain at all times --- infinite support over infinite domains (not to mention the boundary terms). Think of its relation (or non-relation) to the theory of relativity. [Also recall here Einstein's invocation of the relativity principle, 30 years later, for the EPR paper.]
A few months later:
Another miracle! An absolutely incomparable miracle!
Within those few months, Einstein suddenly acquires a mathematical ability far exceeding that of Lorentz, in getting to the correct form of γ. Unlike Lorentz, Einstein is, going by his writing, motivated only from very general kinematical considerations and his two postulates. (Later on, he would recall riding on a light beam etc.) Any specifics of the ED laws (a coupled set of four first-order equations) are totally irrelevant. Also irrelevant, for that matter is the precise form of the light wave equation. Only the fact that c is defined in reference to universal constants, is the relevant matter coming from ED. Nothing else. No other relation, whatsoever to ED.
Pure thought. Miracle!
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This paper by Giacomini is written very well, and gives a lot of more info than I had gathered starting from Wiki articles on history of ED, STR, etc., and other sources. Written in a very straight-forward, concise and clear style, it's an invaluable reference. I don't know about others, but at least I will be unable to bracket this paper under the phrase ``and references therein.''
--Ajit
[Might note corrections, etc., via replies to this comment tomorrow or later. Now, have to hurry, sign off....]
And, by the by, since y'll care enough to think about the Aether:
ReplyDeleteThe *equation* for the *ideal* fluid flow doesn't produce any Aether drag.
But the MHL system (the 4 + 1) already has the *equation* *already* built into it. So says Griffiths.
What does it say? How do you identify the physics corresponding to this conclusion? the ontology? why?
Does the ontology of NM, NG, and CM provide any clue? simply because it's not just MH but the MHL system?
What idea(s), if any, does it suggest towards the ontology of the Aether? Material objects? Electrodynamics? Nothing new to be found, in any?
Ummm....
arXiv! [You must, I tell you one thing. Take it as a verb, not an Ig-Nobel nominated noun. But a verb. You. Y'all.]
--Ajit