A Criticism of 'Gas Mode' Reinterpretations of the Michelson-Morley and Similar Experiments

摘要

It has been argued by R. T. Cahill and others that a Michelson interferometerin "gas mode" - in which the light paths are through an included gaseous medium- are able to detect and have detected an absolute frame of reference. It isshown here that this argument supposes incorrectly that the reduced velocity oflight in gas is an observer-independent invariant. This velocity is notinvariant, but given in a frame with respect to which the interferometer moveswith velocity v by the usual relativistic formula for the addition ofvelocities, these being in this case the velocity v and the reduced velocity oflight in the inertial frame of the interferometer. It is suggested nonethelessthat though the absolute frame urged by Cahill may be undetectable, there arepersuasive grounds for considering the alternative Lorentzian Relativity thatdid suppose the existence of such a frame.