Checking the absolute value of the speed of light in 1D

Abstract

Einstein's theory of relativity establishes that the measurement of the speed of light is constant and invariant in any frame of reference. In this article, we will review that this postulate is fulfilled by applying the Einstein’s velocity addition for the case of one spatial dimension (1D). This work may be of special usefulness for physics students and teachers of pre-university and first-year university levels to introduce relativistic theory.