The Empirical Models of Theoretical Physics

Einstein's general relativity is an empirical concoction - a malleable combination of ad hoc equations and fudge factors allowing Einsteinians to predict anything they want. This means that general relativity has no postulates:

https://www.quora.com/What-are-the-p...ral-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." [end of quotation]

Sometimes Einsteinians call Einstein's 1915 final ad hoc equations "postulates" (we all live in Einstein's schizophrenic world, don't we):

http://math.stanford.edu/~schoen/tri.../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) ..." [end of quotation]

For a deductive theory, demonstrating an absurdity implies that a postulate is false - the theory can be falsified in this way. For a non-deductive model (empirical concoction), demonstrating an absurdity has no consequences because there are no postulates. The demonstrated absurdity remains a small local nuisance, apparently unrelated to other parts of the model, and can be either ignored by the modelers or neutralized by introducing some additional fudge factor.

So in Einstein's general relativity we find the absurdity ("idiocy" is more precise) that the speed of light DECREASES as the light falls towards the source of gravity - in the gravitational field of the Earth the acceleration of falling photons is NEGATIVE, -2g. This is not deduced from postulates of course - the absurdity is a fudge factor Einstein and his mathematical friends had to introduce to make the gravitational redshift and gravitational time dilation compatible:

https://archive.is/wn4PV
Albert Einstein: "Second, this consequence shows that the law of the constancy of the speed of light no longer holds, according to the general theory of relativity, in spaces that have gravitational fields. As a simple geometric consideration shows, the curvature of light rays occurs only in spaces where the speed of light is spatially variable."

https://www.youtube.com/watch?v=FJ2SVPahBzg
"The change in speed of light with change in height is dc/dh=g/c."

http://www.physlink.com/Education/AskExperts/ae13.cfm
"Contrary to intuition, the speed of light (properly defined) decreases as the black hole is approached."

http://www.speed-light.info/speed_of_light_variable.htm
"Einstein wrote this paper in 1911 in German. [...] ...you will find in section 3 of that paper Einstein's derivation of the variable speed of light in a gravitational potential, eqn (3). The result is: c'=c0(1+φ/c^2) where φ is the gravitational potential relative to the point where the speed of light c0 is measured. Simply put: Light appears to travel slower in stronger gravitational fields (near bigger mass). [...] You can find a more sophisticated derivation later by Einstein (1955) from the full theory of general relativity in the weak field approximation. [...] Namely the 1955 approximation shows a variation in km/sec twice as much as first predicted in 1911."

http://www.mathpages.com/rr/s6-01/6-01.htm
"Specifically, Einstein wrote in 1911 that the speed of light at a place with the gravitational potential φ would be c(1+φ/c^2), where c is the nominal speed of light in the absence of gravity. In geometrical units we define c=1, so Einstein's 1911 formula can be written simply as c'=1+φ. However, this formula for the speed of light (not to mention this whole approach to gravity) turned out to be incorrect, as Einstein realized during the years leading up to 1915 and the completion of the general theory. [...] ...we have c_r =1+2φ, which corresponds to Einstein's 1911 equation, except that we have a factor of 2 instead of 1 on the potential term."

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