The Existence of a Universal Frame of Reference, in Which it Propagates Light, is Still an Unresolved Problem of Physics

This article shows that the existence of a universal frame of reference, in which light propagates, is still an unresolved problem of physics. The analyzed articles show that the rejection of the idea of ether due to Michelson-Morley’s and Kennedy-Thorndike’s experiments was too hasty. The zero results of these experiments can be explained by the theory with a universal frame of reference, in which light propagates. The fact that one-way speed of light has never been accurately measured and that there is a well-documented effect showing the anisotropy of space from the perspective of our frame of reference, which is the dipolar anisotropy of cosmic microwave background radiation, further substantiates theories with a universal frame of reference. The article shows that the null result of the Michelson-Morley and Kennedy-Thorndike experiments does not determine the Lorentz symmetry.