# Improved Constraints on Isotropic Shift and Anisotropies of the Speed of Light Using Rotating Cryogenic Sapphire Oscillators

 dc.contributor.author Stanwix, Paul dc.contributor.author Tobar, Michael E. dc.contributor.author Phillips, David F. dc.contributor.author Walsworth, Ronald L. dc.contributor.author Hohensee, Michael A. dc.contributor.author Parker, Steven R. dc.date.accessioned 2012-12-06T15:54:50Z dc.date.issued 2010 dc.identifier.citation Hohensee, Michael A., Paul L. Stanwix, Michael E. Tobar, Stephen R. Parker, David F. Phillips, and Ronald L. Walsworth. 2010. Improved constraints on isotropic shift and anisotropies of the speed of light using rotating cryogenic sapphire oscillators. Physical Review D 82(7): 076001. en_US dc.identifier.issn 1550-2368 en_US dc.identifier.issn 1550-7998 en_US dc.identifier.uri http://nrs.harvard.edu/urn-3:HUL.InstRepos:10001144 dc.description.abstract We demonstrate that Michelson-Morley tests, which detect direction-dependent 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 photon-sector standard model extension parameter $$\tilde\kappa_{tr}$$. 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 time-dependent 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 $$\tilde\kappa_{tr}$$ with a precision of $$7.4 \times 10^{-9}$$. This represents the first constraint on $$\tilde\kappa_{tr}$$ by a Michelson-Morley 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. en_US dc.description.sponsorship Physics en_US dc.description.sponsorship Other Research Unit en_US dc.language.iso en_US en_US dc.publisher American Physical Society en_US dc.relation.isversionof doi:10.1103/PhysRevD.82.076001 en_US dc.relation.hasversion http://arxiv.org/abs/1006.1376 en_US dc.relation.hasversion http://walsworth.physics.harvard.edu/publications/2010_Hohensee_PRD.pdf en_US dash.license LAA dc.subject atomic clock en_US dc.subject time en_US dc.title Improved Constraints on Isotropic Shift and Anisotropies of the Speed of Light Using Rotating Cryogenic Sapphire Oscillators en_US dc.type Journal Article en_US dc.description.version Version of Record en_US dc.relation.journal Physical Review D en_US dash.depositing.author Walsworth, Ronald L. dc.date.available 2012-12-06T15:54:50Z

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Peer reviewed scholarly articles from the Faculty of Arts and Sciences of Harvard University