A Note on the Speed of Light and Lorentz Transformation

Abstract

In 1905, Einstein formulated special relativity. He derived the results of Lorentz and Poincaré by employing two fundamental principles: the postulate of relativity and the postulate of the invariance of the speed of light. This note presents an alternative derivation of the Lorentz transformation. This approach relies solely on the existence of a constant speed C , invariant across all inertial reference frames, and the assumption that coordinate transformations between such frames are given by real and linear functions of space and time. The analysis yields two classes of transformations; one encompasses the Lorentz transformation, while the other is physically untenable.