Optical-cavity tests of higher-order Lorentz violation
  The effects of Lorentz-violating operators of nonrenormalizable dimension in optical resonate cavities are studied. Optical-frequency experiments are shown to provide sensitivity to nondispersive nonbirefringent violations that is many orders of magnitude beyond current constraints from microwave cavities. Existing experiments based on Fabry-Perot and ring resonators are considered as illustrations. 
Matthew Mewes
hep-ph