Relativity without Light by Shan Gao.pdf

== Relativity without light: A further suggestion ==

Shan Gao
Unit for the History and Philosophy of Science and Centre for Time, University of Sydney, NSW 2006, Australia.
Institute for the History of Natural Sciences, Chinese Academy of Sciences, Beijing 100190, P. R. China.

Introduction

Special relativity was originally based on two postulates: the principle of relativity and the constancy of the speed of light. But, as Einstein later admitted to some extent (Einstein 1935), it is an incoherent mixture; the first principle is universal in scope, while the second is only a particular property of light, which has obvious electrodynamical origins in Maxwell’s theory. In fact, there has been a lasting attempt that tries to drop the light postulate from special relativity.

It is found that based only on homogeneity of space and time, isotropy of space and the principle of relativity, one can deduce Lorentz-like transformations with an undetermined invariant speed. Unlike special relativity that needs to assume the constancy of the speed of light, an invariant speed naturally appears in the theory, which has been called relativity without light. This is a surprise indeed...