http://groups.google.ca/group/sci.physics.relativity/msg/dc1ebdf49c01... Tom Roberts: "If it is ultimately discovered that the photon has a nonzero mass (i.e. light in vacuum does not travel at the invariant speed of the Lorentz transform), SR would be unaffected but both Maxwell's equations and QED would be refuted (or rather, their domains of applicability would be reduced)."
http://groups.google.com/group/sci.physics.research/msg/44d3ebf3b94d89ad Tom Roberts: "As I said before, Special Relativity would not be affected by a non-zero photon mass, as Einstein's second postulate is not required in a modern derivation (using group theory one obtains three related theories, two of which are solidly refuted experimentally and the third is SR). So today's foundations of modern physics would not be threatened."
http://arxiv.org/PS_cache/arxiv/pdf/0806/0806.1234v1.pdf Mitchell J. Feigenbaum: "In this paper, not only do I show that the constant speed of light is unnecessary for the construction of the theories of relativity, but overwhelmingly more, there is no room for it in the theory."
http://o.castera.free.fr/pdf/Chronogeometrie.pdf Jean-Marc Lévy-Leblond: "Il se pourrait même que de futures mesures mettent en évidence une masse infime, mais non-nulle, du photon ; la lumière alors n'irait plus à la "vitesse de la lumière", ou, plus précisément, la vitesse de la lumière, désormais variable, ne s'identifierait plus à la vitesse limite invariante. Les procédures opérationnelles mises en jeu par le "second postulat" deviendraient caduques ipso facto. La théorie elle-même en serait-elle invalidée ? Heureusement, il n'en est rien..."
http://o.castera.free.fr/pdf/One_more_derivation.pdf Jean-Marc Levy-Leblond: "The evidence of the nonzero mass of the photon would not, as such, shake in any way the validity of the special relalivity. It would, however, nullify all its derivations which are based on the invariance of the photon velocity."
http://phys.org/wire-news/111309179/extending-einsteins-theory-beyond... "University of Adelaide applied mathematicians have extended Einstein's theory of special relativity to work beyond the speed of light. (...) "Our approach is a natural and logical extension of the Einstein Theory of Special Relativity, and produces anticipated formulae without the need for imaginary numbers or complicated physics." The research has been published in the prestigious Proceedings of the Royal Society A in a paper, 'Einstein's special relativity beyond the speed of light'. Their formulas extend special relativity to a situation where the relative velocity can be infinite, and can be used to describe motion at speeds faster than light."
"A natural and logical extension of the Einstein Theory of Special Relativity" means that a valid deductive chain exists between Einstein's 1905 postulates and the new formulas. This is obviously not the case.
In fact, Einstein's relativity stopped being deductive shortly after 1905. Rather, arbitrary manipulation of the equations until the desired predictions are obtained became the main method. The introduction and withdrawal of the cosmological constant and the long and painful adaptation of the theory to the Mercury's perihelion anomaly are typical examples.
CONCLUSION: In gravitation-free space, the speed of light (as measured by the receiver) varies with the speed of the receiver.
VALIDITY OF THE ARGUMENT: The emitter (E) and the receiver (R) are at rest: E at the earth surface, R at a distance h above E. In accordance with the PREMISE, the receiver measures the speed of light to be c'=c(1-gh/c^2). This scenario is equivalent to one in which E and R are fixed in an elevator accelerating, in gravitation-free space, with constant acceleration g in the direction E->R. So when the light signal reaches R, R has acquired speed v=gh/c. Accordingly, the receiver in the elevator measures the speed of light to be c'=c(1-gh/c^2)=c-v.
http://arxiv.org/pdf/1207.1002.pdf Sabine Hossenfelder: "Once a measurement has been made, observables are subject to the laws of special relativity, and the process of measurement introduces a preferred frame. The speed of light can take on different values, both superluminal and subluminal (with respect to the usual value of the speed of light), without the need for Lorentz-invariance violating operators and without tachyons."
Texts of this kind (which are commonplace in the relativistic literature) act like the face of Medusa the Gorgon - on seeing them, clever scientists get paralysed and may never fully recover. As a result, Divine Albert's Divine Theory is immortal.