Improved constraints on isotropic shift and anisotropies of the speed of light using rotating cryogenic sapphire oscillators
Abstract
We demonstrate that MichelsonMorley tests, which detect directiondependent anisotropies in the speed of light, can also be used to place limits upon isotropic deviations of the vacuum speed of light from c, as described by the photonsector standard model extension parameter κ̃_{tr}. A shift in the speed of light that is isotropic in one inertial frame implies anisotropic shifts in others. Using observer Lorentz covariance, we derive the timedependent variations in the relative resonance frequencies of a pair of electromagnetic resonators that would be generated by such a shift in the rest frame of the Sun. A new analysis of a recent experimental test of relativity using this result constrains κ̃_{tr} with a precision of 7.4×10^{9}. This represents the first constraint on κ̃_{tr} by a MichelsonMorley experiment and the first analysis of a single experiment to simultaneously set limits on all nine nonbirefringent terms in the photon sector of the minimal standard model extension.
 Publication:

Physical Review D
 Pub Date:
 October 2010
 DOI:
 10.1103/PhysRevD.82.076001
 arXiv:
 arXiv:1006.1376
 Bibcode:
 2010PhRvD..82g6001H
 Keywords:

 03.30.+p;
 06.30.Ft;
 11.30.Cp;
 12.60.i;
 Special relativity;
 Time and frequency;
 Lorentz and Poincare invariance;
 Models beyond the standard model;
 High Energy Physics  Phenomenology;
 General Relativity and Quantum Cosmology;
 Physics  Data Analysis;
 Statistics and Probability
 EPrint:
 Phys.Rev.D82:076001,2010