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Tests of relativity using a microwave resonator

Peter Wolf·Sébastien Bize·André Clairon·André N. Luiten·Giorgio Santarelli·Michael E. Tobar
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Abstract

The frequencies of a cryogenic sapphire oscillator and a hydrogen maser are compared to set new constraints on a possible violation of Lorentz invariance. We determine the variation of the oscillator frequency as a function of its orientation (Michelson-Morley test) and of its velocity (Kennedy-Thorndike test) with respect to a preferred frame candidate. We constrain the corresponding parameters of the Mansouri and Sexl test theory to $δ- β+ 1/2 = (1.5\pm 4.2) \times 10^{-9}$ and $β- α- 1 = (-3.1\pm 6.9) \times 10^{-7}$ which is equivalent to the best previous result for the former and represents a 30 fold improvement for the latter.

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Peter Wolf, Sébastien Bize, André Clairon, André N. Luiten, Giorgio Santarelli, Michael E. Tobar. 2002-10-16. Tests of relativity using a microwave resonator. https://doi.org/10.1103/physrevlett.90.060402

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