Particle-Accelerator Constraints on Isotropic Modifications of the Speed of Light

Michael A Hohensee,Ralf Lehnert,David F Phillips,Ronald L Walsworth

doi:10.1103/physrevlett.102.170402

Abstract

The absence of vacuum Cherenkov radiation for 104.5 GeV electrons and positrons at the LEP collider at CERN combined with the observed stability of 300 GeV photons at the Tevatron constrains deviations of the speed of light relative to the maximal attainable speed of electrons. Within the standard-model extension, the limit -5.8x10(-12)<or=kappatr-4/3ce00<or=1.2x10(-11) is extracted, which sharpens previous bounds by more than 3 orders of magnitude. The potential for further refinements of this limit with terrestrial experiments and astrophysical observations is discussed.

Highlights

The absence of vacuum Cherenkov radiation for 104.5 GeV electrons and positrons at LEP combined with the observed stability of 300 GeV photons at the Tevatron constrains deviations of the speed of light relative to the maximal attainable speed of electrons
A general theoretical description of weak Lorentz symmetry breaking at low energies is provided by the Standard-Model Extension (SME), which contains the usual Standard Model and General Relativity as limiting cases [2, 3]
The SME has served as the basis for numerous Relativity tests in many physical systems [4, 5, 6]

Summary

Introduction

The absence of vacuum Cherenkov radiation for 104.5 GeV electrons and positrons at LEP combined with the observed stability of 300 GeV photons at the Tevatron constrains deviations of the speed of light relative to the maximal attainable speed of electrons. Michael A., Ralf Lehnert, David Forrest Phillips, and Ronald L. This allows charges in a Lorentz-violating (κtr > 0) vacuum to move faster than the modified speed of light c/n and to become unstable against the emission of Cherenkov photons. We employ the absence of these two effects for electrons at LEP and photons at the Tevatron to derive improved limits at the 10−11 level on κtr c0e0, a quantity that describes differences between the speed of light and the electron’s MAS.

Results

Conclusion