Astrophysical Limit on the Deformation of the Poincare Group

Abstract

The deformed Poincaré group contains a characteristic mass, $\kappa$. At energies exceeding $\kappa$, deviations from the special theory of relativity become significant. However, small deviations from ordinary relativistic kinematics are observable even at energies substantially lower than $\kappa$. The observation of distant events producing ultra high energy (UHE) particles leads to a lower limit on $\kappa$. From an analysis of the UHE data on the burst in the binary system HER X1 in 1986, we deduce $\kappa >1.310^{12}$~GeV.

Comments: SKD@JHUP.PHA.JHU.EDU 7 pages; 1 figure available upon request. Report # JHU-TIPAC920027/rev hep-ph/yymmnnn --- Latex