Abstract

The one-way speed of light on the surface of the rotating Earth is determined using modern GPS technology. One method employs the GPS clock synchronization algorithm while the other is based on light speed isotropy in the Earth Centered Inertial frame that is critical to GPS operation. Using these two methods it is easily shown that light travels faster West than East relative to the surface of the Earth. This finding directly contradicts Einstein’s principle of light speed constancy and thereby invalidates the Lorentz transformations and special relativity theory for which the principle is a fundamental requirement. The Selleri transformations are presented as the space-time transformations that best represent the physical world.