Can the anomalous precession of the orbit of Mercury be explained just with relativistic length contraction?

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    $\begingroup$ No. If it could we wouldn't need general relativity to explain it. $\endgroup$ – John Rennie May 2 '19 at 16:21
  • $\begingroup$ @JohnRennie That sounds like a good answer. $\endgroup$ – G. Smith May 2 '19 at 16:25
  • $\begingroup$ @G.Smith possibly a bit brief for an answer :-) $\endgroup$ – John Rennie May 2 '19 at 16:30

No. Before Einstein came up with General Relativity, physicists tried various special-relativistic generalizations of Newtonian gravity. They didn’t work, and no one has found one since that works.

By contrast, General Relativity can explain not just the anomalous precession of Mercury, but everything else we have observed about gravity.

  • $\begingroup$ I would be interested in references to such attempts. $\endgroup$ – my2cts May 2 '19 at 20:32
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    $\begingroup$ @my2cts In the section “Lorentz-invariant models (1905-1910)”, en.wikipedia.org/wiki/Alternatives_to_general_relativity mentions failed attempts by Poincaré, Minkowski, and Sommerfeld. $\endgroup$ – G. Smith May 2 '19 at 20:38
  • $\begingroup$ Well, not "everything". There are UV (big bang/black hole singularity) and IR (cosmological constant) problems still. $\endgroup$ – Avantgarde May 3 '19 at 14:09
  • $\begingroup$ @Avantgarde I said “observed”. We haven’t observed gravity’s UV regime, and a cosmological constant (but not an explanation of it) is part of GR. $\Lambda$ is in some sense more basic than $G$ because it simply is the coefficient of the zero-order-of-curvature term in the gravitational action. $\endgroup$ – G. Smith May 3 '19 at 16:39
  • $\begingroup$ @G.Smith Yes, but $\Lambda$ is just one way. There are other infrared modifications of gravity too, like ghost condensation, non-local gravity, etc. $\endgroup$ – Avantgarde May 3 '19 at 19:02

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