Absolute motion determined from Michelson-type experiments in optical media
The symmetry of vacuum is characterized by the Lorentz group with the parameter $c$. Physical space inside the homogeneous optical medium should be described by the Lorentz group with the parameter $c/n$, where $n$ is the refractive index of the medium. Violation of a one-parameter phenomenological symmetry in the discrete medium, such as gas, creates the opportunity for the experimental detecting the motion of the optical medium relative to luminiferous aether.