On the theory of flat spacetime

Abstract

Special relativity turns out to be more than coordinate transformations in which the constancy of the speed of light plays the central role between two inertial reference frames. Special relativity, in essence, is a theory of four-dimensional flat spacetime. Euclidian space spans three of the spacetime's dimensions and time spans the fourth. Properties of light may not be needed to describe spacetime, which exists independently of light. The article shows that a theory of spacetime can be constructed from a geometric viewpoint in which the speed of light does not play any role. Moreover postulating four-dimensional geometry significantly simplifies the concept of special relativity.