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Special relativity derives from two postulates:

  1. Invariance of $c$

  2. Principle of relativity

The same axiomatic procedure is possible for quantum mechanics. Now, does exist a set of axioms for general relativity in order the derive the theory in a straightforward way? I would say that one of them is the "equivalence principle" and the others?

DanielSank
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Yildiz
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    Related/possible duplicates: http://physics.stackexchange.com/q/259065/50583, http://physics.stackexchange.com/q/219681/50583 – ACuriousMind Jan 05 '17 at 16:30
  • I would add the clock postulate (doesn't seem necessary for SR, but looks necessary for GR else you cannot move on from the equivalence principle). –  Jan 05 '17 at 16:48
  • Here, I must simply point out a few fabulous videos on YouTube (playlist can be found here). (I may make an answer later summarizing the points made.) – auden Jan 06 '17 at 16:21

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Einstein's general relativity has no postulates:

https://www.quora.com/What-are-the-postulates-of-General-Relativity What are the postulates of General Relativity? Alexander Poltorak, Adjunct Professor of Physics at the CCNY:

In 2005 I started writing a paper, “The Four Cornerstones of General Relativity on which it doesn’t Rest.” Unfortunately, I never had a chance to finish it. The idea behind that unfinished article was this: there are four principles that are often described as “postulates” of General Relativity:

  1. Principle of general relativity

  2. Principle of general covariance

  3. Equivalence principle

  4. Mach principle

The truth is, however, that General Relativity is not really based on any of these “postulates” although, without a doubt, they played important heuristic roles in the development of the theory.

Sometimes Einsteinians absurdly call the final equations of general relativity "postulates":

http://math.stanford.edu/~schoen/trieste2012/lecture_3.pdf

Postulates of General Relativity Postulate 1: A spacetime (M^4, g) is a Riemannian 4-manifold M^4 with a Lorentzian metric g. Postulate 2: A test mass beginning at rest moves along a timelike geodesic. (Geodesic equation) ... Postulate 3: Einstein equation is satisfied. (Einstein equation) ..."

Special relativity is deductive (even though a false postulate and an invalid argument spoiled it from the very beginning) but general relativity is an empirical model, analogous to the empirical models defined here:

http://collum.chem.cornell.edu/documents/Intro_Curve_Fitting.pdf

The objective of curve fitting is to theoretically describe experimental data with a model (function or equation) and to find the parameters associated with this model. Models of primary importance to us are mechanistic models. Mechanistic models are specifically formulated to provide insight into a chemical, biological, or physical process that is thought to govern the phenomenon under study. Parameters derived from mechanistic models are quantitative estimates of real system properties (rate constants, dissociation constants, catalytic velocities etc.). It is important to distinguish mechanistic models from empirical models that are mathematical functions formulated to fit a particular curve but whose parameters do not necessarily correspond to a biological, chemical or physical property."

dmckee --- ex-moderator kitten
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Pentcho Valev
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  • What are the false postulate and invalid argument you refer to? – NoethersOneRing Jan 05 '17 at 19:36
  • If the fact that the rate of a clock doesn't depend on its acceleration isn't a postulate, then you can prove it. How do you prove it? –  Jan 05 '17 at 20:08
  • What deals curve fitting with my question? – Yildiz Jan 05 '17 at 20:33
  • "What are the false postulate and invalid argument you refer to?" See my answer here: http://physics.stackexchange.com/questions/246727/presentism-doesnt-everything-exist-at-the-same-moment – Pentcho Valev Jan 05 '17 at 20:35
  • I fixed the quotation markup, but I suspect that you still need to (a) correctly represent the math and (b) do a better job of indicating places where you elide some of the quoted material. You've been using this site long enough that other people shouldn't have to do this stuff for you any more. Good writing includes making clear use of standard typesetting conventions, and that included how you indicate quoted material. – dmckee --- ex-moderator kitten Jan 05 '17 at 22:39
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    Einstein's field equation is a postulate, for the same reason that Newton's $F=ma$ is a postulate. – user1504 Jan 06 '17 at 00:08
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    @ Pentcho Valev I like very much your demonstration of the clock postulate. BTW, who are the Einsteinians you are talking about with such respect? Are they a category of brainless people you do not belong to? –  Jan 06 '17 at 10:56
  • "BTW, who are the Einsteinians you are talking about with such respect? Are they a category of brainless people you do not belong to?" Here are a few typical Einsteinians: https://m.youtube.com/watch?v=BuxFXHircaI – Pentcho Valev Jan 07 '17 at 00:16
  • @ Pentcho Valev : excellent! BTW, you didn't answer my question regarding the clock postulate, that was a serious question, I would be interested by your point of view. –  Jan 08 '17 at 09:28
  • Uh..."Einsteinians"? People like Michio Kaku, Brian Cox, Neil deGrasse Tyson, Brian Greene and Lisa Randall? You mean "physicists"? – Alex Nelson Feb 05 '17 at 03:06