Fresnel Drag vs. Einstein Velocity a Case for Further Investigation
When the group velocity, as opposed to the phase velocity, of light is measured, Einstein's predictions for one-way light velocities in a transparent medium differ from Fresnel's predictions by substantial amounts, even at speeds as low as our speed relative to the Cosmic Microwave Background Radiation (365,000 m/s). Calculations show that if Einstein is wrong, then a measurable light round-trip time difference will be found between clockwise and counterclockwise fiber optic light paths, where each light path has synthetic fused silica fiber in one direction and air-core fiber in the other direction. The magnitude of the difference will be a function of velocity of the experiment and observer (both the same) relative to a presently unknown preferred reference frame (i.e. a frame preferred by physics not by physicists for convenience). If the light round-trip time difference is measured on an oscilloscope and the length of the loops is about 1,000 m, then a speed as low as 365,000 m/s relative to the preferred reference frame can be detected.