ON THE ELECTRODYNAMICS OF MOVING BODIES
By A. Einstein, June 30, 1905
"We will raise this conjecture (the purport of which will hereafter be called the "Principle of Relativity'') to the status of a postulate, and also introduce another postulate, which is only apparently irreconcilable with the former, namely, that light is always propagated in empty space with a definite velocity c which is independent of the state of motion of the emitting body."
Nowadays the statement "the speed of light is variable in the presence of a gravitational field" implies nothing for the majority of physicists (rationality in science does not exist anymore) but in 1907 Einstein knew that if the speed of light varies with the gravitational potential, then it varies with the speed of the observer as well (that is, his 1905 light postulate is false):
John Norton: "Already in 1907, a mere two years after the completion of the special theory, he [Einstein] had concluded that the speed of light is variable in the presence of a gravitational field."
Lee Smolin: "Special relativity was the result of 10 years of intellectual struggle, yet Einstein had convinced himself it was wrong within two years of publishing it."
The fundamental nightmare has always been forcing high priests in Einsteiniana to undermine, camouflage, even deny the crucial role of Einstein's 1905 false light postulate. Here is the latest attempt:
Tom Roberts (the most famous Einsteinian on sci.physics.relativity):
You absolutely must have this postulate:
1. (the Principle of Relativity) The laws by which the states of physical systems undergo change are not affected, whether these changes be referred to the one or the other of any two inertial frames.
Indeed, with just that postulate and the "hidden postulates" of SR [#], one can derive three theories based on the Euclid, Galilei, and Lorentz groups (this illustrates the power of group theory). Only the third survives experimental tests, and is known as SR.
[#] That is what Einstein called them in a 1907 paper; they are:
* the usual definition of inertial frames (on a flat manifold)
* space is homogeneous and isotropic
* time is homogeneous
* clocks and rulers have no memory
Note, in particular, that light is not mentioned at all. It is an EXPERIMENTAL issue that the vacuum speed of light turns out to be equal to the constant c in the Lorentz transforms. That leads to the identification of the constant c in the Lorentz transforms with the constant c in Maxwell's equations, which then leads to the unification of classical electrodynamics and SR (historically, SR was derived from an assumption of that unification).
End of Tom Roberts' camouflage
Previous attempts by Tom Roberts and other high priests to undermine, camouflage, even deny the crucial role of Einstein's 1905 false light postulate:
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)."
Why Einstein was wrong about relativity
29 October 2008, Mark Buchanan, NEW SCIENTIST
"This "second postulate" is the source of all Einstein's eccentric physics of shrinking space and haywire clocks. And with a little further thought, it leads to the equivalence of mass and energy embodied in the iconic equation E = mc2. The argument is not about the physics, which countless experiments have confirmed. It is about whether we can reach the same conclusions without hoisting light onto its highly irregular pedestal. (...) But in fact, says Feigenbaum, both Galileo and Einstein missed a surprising subtlety in the maths - one that renders Einstein's second postulate superfluous."
Jean-Marc Lévy-Leblond "De la relativité à la chronogéométrie ou: Pour en finir avec le "second postulat" et autres fossiles": "D'autre part, nous savons aujourd'hui que l'invariance de la vitesse de la lumière est une conséquence de la nullité de la masse du photon. Mais, empiriquement, cette masse, aussi faible soit son actuelle borne supérieure expérimentale, ne peut et ne pourra jamais être considérée avec certitude comme rigoureusement nulle. 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 ; mais, pour s'en assurer, il convient de la refonder sur des bases plus solides, et d'ailleurs plus économiques. En vérité, le premier postulat suffit, à la condition de l'exploiter à fond."
Jean-Marc Levy-Leblond: "This is the point of view from wich I intend to criticize the overemphasized role of the speed of light in the foundations of the special relativity, and to propose an approach to these foundations that dispenses with the hypothesis of the invariance of c. (...) We believe that special relativity at the present time stands as a universal theory discribing the structure of a common space-time arena in which all fundamental processes take place. (...) 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."
Jong-Ping Hsu: "The fundamentally new ideas of the first purpose are developed on the basis of the term paper of a Harvard physics undergraduate. They lead to an unexpected affirmative answer to the long-standing question of whether it is possible to construct a relativity theory without postulating the constancy of the speed of light and retaining only the first postulate of special relativity. This question was discussed in the early years following the discovery of special relativity by many physicists, including Ritz, Tolman, Kunz, Comstock and Pauli, all of whom obtained negative answers."