A theory developed by Albert Einstein stating that the laws of motion are the same for all inertial (non-accelerating) frames of reference and that the speed of light (in a vacuum) is the same for all ...

The Sagnac effect, first observed over a century ago, remains central to our understanding of relativistic kinematics and the operational definitions of simultaneity. Fundamentally, this effect arises ...

At present, mainstream physicists seem to have fully accepted Einstein's Special Theory of Relativity (STR) and to take it as the foundation of modern physics because the theory appears perfectly ...