A Michelson-Morley Test of Lorentz Symmetry for Electrons

Understand

All evidence so far suggests that the absolute spatial orientation of an experiment never affects its outcome.

• This is reflected in the Standard Model of physics by requiring all particles and fields to be invariant under Lorentz transformations.
• The most well-known test of this important cornerstone of physics are Michelson-Morley-type experiments\cite{MM, Herrmann2009,Eisele2009} verifying the isotropy of the speed of light.
• Lorentz symmetry also implies that the kinetic energy of an electron should be independent of the direction of its velocity, \textit{i.e.,} its dispersion relation should be isotropic in space.