Letter to the Editor
Pulsar radiation and quantum gravity
Received 21 December 1998 / Accepted 29 March 1999
Quantum gravity may lead to an energy dependence in the speed of light. The high energy radiation from gamma-ray pulsars can be used to place limits on such effects. We find that emission from the Crab pulsar at energies above 2 GeV trails that at 70-100 MeV by no more than 0.35 ms (95% confidence) and place a lower bound on the energy scale of quantum gravitational effects on the speed of light of . This bound might be improved by two orders of magnitude by observation of pulsations from the Crab at higher energies, 50-100 GeV, in the near future.
Key words: gravitation stars: pulsars: general stars: pulsars: individual: Crab gamma rays: observations
© European Southern Observatory (ESO) 1999
Online publication: April 19, 1999