Comment on “Generalization of Einstein’s synchronization for the case of anisotropic light speed”1Appears in Can. J. Phys. 87, 969.

In a recent article, A. Sfarti attempted to derive the frame-invariance of the speed of light from the principle of relativity, thereby eliminating the second postulate from the foundations of special relativity (Can. J. Phys. 87, 969 (2009)). I analyse his derivation and conclude that it is incorrect.

Generalization of Einstein’s synchronization for the case of anisotropic light speed

The current paper derives a generalized version of Einstein’s clock synchronization rule for the case of inertial frames in which light speed is assumed to be anisotropic. The current paper is the result of a discussion started with Professor N.D. Mermin. We show how we can construct the theory of relativity from only one base principle: the postulate of relativity. The postulate of relativity is the requirement that the equations, describing the laws of physics, have the same form (are covariant) in all admissible frames of reference.