Test of constancy of speed of light with rotating cryogenic optical resonators

TL;DR

This study tests the constancy of the speed of light using rotating cryogenic optical resonators, providing highly precise limits on Lorentz invariance violations and setting new bounds on parameters in the Standard Model Extension.

Contribution

It presents the most precise experimental test of Lorentz invariance for electromagnetic waves using rotating cryogenic optical resonators, improving previous limits by an order of magnitude.

Findings

Improved the limit on the Robertson-Mansouri-Sexl parameter to (+0.5±3±0.7)×10⁻¹⁰.

Set a new upper limit for the Standard Model Extension parameter |(κ̃_{e-})^{ZZ}| < 2×10⁻¹⁴.

Demonstrated the effectiveness of cryogenic optical resonators in fundamental physics tests.

Abstract

A test of Lorentz invariance for electromagnetic waves was performed by comparing the resonance frequencies of two optical resonators as a function of orientation in space. In terms of the Robertson-Mansouri-Sexl theory, we obtain $\beta-\delta-1/2=(+0.5\pm 3\pm 0.7) E-10$, a ten-fold improvement compared to the previous best results. We also set a first upper limit for a so far unknown parameter of the Standard Model Extension test theory, $|(\tilde{\kappa}_{e-})^{ZZ}| < 2\cdot E-14$.