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Einstein dedicated his time between 1905-1915 to develop general relativity (GR). It seems strange to me that no other physicists attempted to tackle this problem in this ten-year period. After all, developing a relativistic theory of gravity superseding Newton's should have been the holy grail of physics at that period. How come none gave it a shot?

Contrast this with quantum electrodynamics where a lot of physicists (Feynman, Dyson, Schwinger, Tomonaga, etc.) rushed/raced to develop the theory. Even other scientists/mathematicians (e.g., Marcel Grossmann) intended only to help/guide Einstein, but not compete with him.

No one independently tackled the problem except for Hilbert who successfully discovered the Einstein field equations in 1915 simultaneously with Einstein. But this is very late, given that Einstein had already been working on it for 10 years. Moreover, this suggests that other eminent physicists might have been able to develop GR if only they attempted to work on it in.

So are there any (failed) attempts at developing GR in 1905-1915 by other scientists? If not, how come no one gave it a shot in ten years given the importance of the problem?

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    $\begingroup$ Lorentz-invariant theory of gravity existed before Einstein and special relativity, Lorentz formulated it in 1900. There was little need for more experimentally, the perihelion of Mercury exercised very few because Seeliger's zodiacal light explained it well enough. Einstein wasn't alone. Like him, Poincare, Minkowski and Sommerfeld in 1905-10 were mostly motivated by philosophical and mathematical issues like invariance. It picked up somewhat after 1912, but GR remained little needed even after Einstein's formulation in 1915. $\endgroup$ – Conifold Dec 5 '20 at 16:46
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    $\begingroup$ That the only people in the world to successfully work on GR at that time were the world’s greatest physicist and the worlds greatest mathematician, does not suggest that other physicists could have solved it if they had only tried. $\endgroup$ – RBarryYoung Dec 5 '20 at 20:43
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    $\begingroup$ It was even worse than you make out. Most of Einstein's peers were bemused and dismissive of his attempts. It was a long odyssey with very little sympathy. Looking at his letters and biography and discussions after conference talks, one sees this. Only Lorentz, Sommerfeld, Ehrenfest, Hilbert, and Klein were sympathetic. To most everyone else, it seemed a bizarre, philosophic, unphysical, quixotic enterprise. $\endgroup$ – joseph f. johnson Dec 6 '20 at 19:32
  • $\begingroup$ To rephrase Joseph F. Johnson above, Einstein was considered a quack in his day. So his theories got about as much professional respect as do the theories of today's quacks. $\endgroup$ – dotancohen Dec 7 '20 at 18:02
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    $\begingroup$ @dotancohen How come he got the Nobel, the Royal Society Copley Medal, the Gold Medal of the Royal Astronomical Society, and the Max Planck medal of the German Physical Society, all before 1930? Some quack. $\endgroup$ – Michael Harvey Dec 8 '20 at 18:49
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From the rough understanding of the physics of the era I have, I would say there are at least two main reasons as to why it is actually quite expected that finding a relativistic theory of gravity wouldn't be the priority of the majority of physicists.

  • The holy grail of physics was quantum mechanics since the mid-1900s if not from the beginning of the century itself. Planck proposes the light-quanta based solution to the blackbody radiation problem in 1900, kicking off the quantum era. Thompson proposes the so-called plum-pudding model of the atom in 1904. Einstein comes up with his explanation of the photoelectric effect in 1905, elevating the status of photons from a mathematical trick in Planck's idea to a real physical thing. Milikan shows the quantization of charge in 1907 with the famous oil-drop experiment. Rutherford does the gold-foil experiment showing that the atom has a nucleus in 1911. Finally, Bohr introduces the historic Bohr model of the atom in 1913. As you can see, the world of quantum mechanics is continuously action-packed in the era with which we are concerned.

  • On the other hand, special relativity wasn't noticed at all in 1905. The acceptance and awareness of special relativity began around 1909 when Planck compared it to be a revolutionary step of the order of the Copernican revolution. A major step in the acceptance of special relativity was the development of the geometric formulation of special relativity by Minkowski in 1907 which also took some time to get acceptance (funnily enough, Einstein himself wasn't quite kind to his old teacher Minkowski about his funny four-dimensional diagrams). While most physicists accepted special relativity by around 1911-1912, it still was a controversial subject, to say the least. Einstein was nominated (along with Lorentz) for the Nobel prize in physics for special relativity but the Nobel committee had decided against it, in part because the old guard of physics still believed in the aether theory.

In addition to it being unlikely that finding a relativistic theory of gravity is the top priority of many physicists, the first physical insight which led to general relativity was put in its furnished form only in 1911 when Einstein laid out the equivalence principle in detail which he had introduced in 1907 earlier. In any case, just like Einstein, all other physicists were completely unaware of the machinery of differential geometry which was needed to mathematically formulate a theory that utilized the equivalence principle. So, it makes sense that it was a mathematician who actually tried to do it, namely, Hilbert. Also, given how much of an esoteric and a purely theoretical subject general relativity was considered even after it was "completed" in 1915 (until the 60s and the 70s when the likes of John Wheeler revived it), one can imagine how esoteric it would have been considered before 1915. People had much more tangible work to do in quantum mechanics.

Despite all these reasons, Hilbert was by no means the only person other than Einstein who worked on it. As is famous, Emmy Noether (another mathematician) worked on it, helping Hilbert. In fact, Poincare tried to create his own relativistic theory of gravity by trying to modify Newton's law of gravity in analogy with the relativistic Maxwell's equations as early as 1905. In around 1912, Abraham and Mile formulated a scalar theory of gravity which was Lorentz invariant but failed to satisfy the equivalence principle. The most impressive effort was by Nordstrom who actually formulated a self-consistent scalar theory of gravity in 1912-1913, consistent with both Lorentz invariance and the equivalence principle, but it violated the requirement of general covariance which Einstein thought was crucial. In the end, as we know, Einstein's general theory of relativity which was a tensor theory was consistent with Lorentz invariance, equivalence principle, as well as general covariance--and most importantly, has matched in its predictions with all the experiments so far.

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    $\begingroup$ By “mid-1900s” did you mean “middle of 1900-1910” rather than “middle of 20th century”? The latter is a more common meaning (as with mid-1700s, etc.) but is an awkward fit to the timeline in your answer. Separately, should your “by around 1912-1912” be 1911-1912 or 1912-1913? $\endgroup$ – KCd Dec 5 '20 at 18:11
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    $\begingroup$ This always gets me. I was taught that the 'XX00s' were the first decade of a century. It always look odd to read that HG Wells was born in 'the 1800s'. That's Napoleon, Trafalgar, etc. $\endgroup$ – Michael Harvey Dec 5 '20 at 20:22
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    $\begingroup$ @MichaelHarvey That's what comes from using the valid digit "0" as a placeholder. It's ambiguous whether "1900s" refers to years of the form "19xx" or "190x". (That said, verbally the distinction is usually made by referring to the 100-year period as "the nineteen hundreds" and the decade as the "the nineteen aughts" or something similar.) $\endgroup$ – chepner Dec 5 '20 at 23:28
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    $\begingroup$ @MichaelHarvey : Ah, well, that's the solution then! Just say ‘in the Edwardian era’. Now to figure out how to distinguish the 2000s from the 2000s (not the mention the 2000s, which we'll need in a few more decades). $\endgroup$ – Toby Bartels Dec 6 '20 at 7:51
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    $\begingroup$ I took me a long time to realize that GR had been developed before the Great War. I somehow always thought "the 50s and 60s". High school should insist on giving the timeline of math and science instead of making people learn by rote the date when Louis XIV had a spectacular bowel movement. $\endgroup$ – David Tonhofer Dec 6 '20 at 23:11
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Your claim is simply not true: there was work published by Einstein, Hilbert, Nordstrom, and (slightly later) Whitehead. It was a very hard problem, so undoubtedly for every person who came up with something publishable, there were many others who tried but who we don't know about.

This was also very early for anyone to be working on such a theory, based on the state of the art. There was no motivation for working on a relativistic theory of gravity unless you already believed that special relativity was correct. But SR was a new and almost completely untested. The evidence in its favor was indirect and could be interpreted in other ways. For example, Michelson and Morley believed that their original experiment had been a failure because it didn't produce the "right" result, and as late as 1925 their successors were trying to get a correct, positive result by redoing it on Mt. Wilson. A 1925 paper in Nature by Miller describing a positive (!) Mt. Wilson result doesn't even mention special relativity, and Miller was still publishing this type of material in 1933. Detailed, unambiguous experimental evidence for SR didn't come until experiments like Ives-Stilwell in 1938.

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People have been working on extending Newtonian gravity ever since Newton discovered it. The major problem of the theory, as admitted by Newton, was its 'action at a distance' character and for which he was unable to come up with a solution. As various people worked on those extensions, the generic term for the medium of transmission was called the aether. Notably, given the prominence of mechanics, the aether was hypothesised mechanically.

It's only after electromagnetism was discovered with Faraday introduced his lines of force that another way of conceptualising the aether came to the fore, that is by the field. A number of authors were working on aetherial theory of gravity, the most important of which, according to Einstein, was Nordstroms scalar-tensor theories. His second theory even satisfied Einsteins weak equivalence principle!

However, it failed to predict light deflection and also the anomalous precession of Mercury, which Einsteins 1915 theory did.

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    $\begingroup$ This doesn't answer the question. $\endgroup$ – Ben Crowell Dec 5 '20 at 18:56
  • $\begingroup$ @Ben Crowell: Why? $\endgroup$ – Mozibur Ullah Dec 5 '20 at 19:00
  • $\begingroup$ @Ben Crowell: Do you normally do this? Offer a bald assertion without any explanation? $\endgroup$ – Mozibur Ullah Dec 5 '20 at 19:09
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    $\begingroup$ @MoziburUllah The question asks about general relativity, and you've answered about special relativity. $\endgroup$ – wizzwizz4 Dec 6 '20 at 11:42
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    $\begingroup$ @wizzwizz4: I've actually answered about General Relativity. $\endgroup$ – Mozibur Ullah Dec 6 '20 at 21:37

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