Gamma-ray and cosmic-ray tests of Lorentz invariance violation and quantum gravity models and their implications

Abstract

The topic of Lorentz invariance violation (LIV) is a fundamental question in physics that has taken on particular interest in theoretical explorations of quantum gravity scenarios. I discuss various γ-ray observations that give limits on predicted potential effects of Lorentz invariance violation. Among these are spectral data from ground based observations of the multi-TeV γ-rays from nearby AGN, INTEGRAL detections of polarized soft γ-rays from the vicinity of the Crab pulsar, Fermi Gamma Ray Space Telescope studies of photon propagation timing from γ-ray bursts, and Auger data on the spectrum of ultrahigh energy cosmic rays. These results can be used to seriously constrain or rule out some models involving Planck scale physics. Possible implications of these limits for quantum gravity and Planck scale physics will be discussed. © 2010 American Institute of Physics.