New indirect bounds on Lorentz violation in the photon sector

TL;DR

This paper derives new indirect bounds on Lorentz violation in the photon sector using cosmic-ray air shower observations, improving constraints from previous laboratory experiments and discussing potential physics implications.

Contribution

It introduces novel indirect bounds on Lorentz-violating parameters in the photon sector based on cosmic-ray air shower data, surpassing previous laboratory limits.

Findings

New bounds range from 10^{-15} to 10^{-19} on Lorentz violation parameters.

Cosmic-ray air shower observations provide a powerful method for testing fundamental physics.

Implications for physics beyond the Standard Model are briefly discussed.

Abstract

Direct laboratory bounds on the 9 nonbirefringent Lorentz-violating dimensionless parameters of modified-Maxwell theory range from the 10^{-7} level to the 10^{-16} level. The detection of air showers initiated by charged primaries (ultrahigh-energy cosmic-rays) and neutral primaries (TeV gamma-rays) allows us to obtain new indirect bounds ranging from the 10^{-15} level to the 10^{-19} level. Possible physics implications are briefly discussed.