Severe Limits on Variations of the Speed of Light with Frequency
Abstract
Explosive astrophysical events at high redshift can be used to place severe limits on the fractional variation in the speed of light with frequency ( Δc/c), the photon mass ( m_{γ}), and the energy scale of quantum gravity ( E_{QG}). I find Δc/c<6.3×10^{21} based on the simultaneous arrival of a flare in GRB 930229 with a rise time of 220+/30 μs for photons of 30 and 200 keV. The limit on m_{γ} is 4.2×10^{44} g for GRB 980703 from radio to gamma ray observations. The limit on E_{QG} is 8.3×10^{16} GeV for GRB 930131 from 30 keV to 80 MeV photons.
 Publication:

Physical Review Letters
 Pub Date:
 June 1999
 DOI:
 10.1103/PhysRevLett.82.4964
 arXiv:
 arXiv:astroph/9810479
 Bibcode:
 1999PhRvL..82.4964S
 Keywords:

 Astrophysics
 EPrint:
 7 pages, Submitted to PRL