Accelerated observers and gravitational radiation

Abstract

We evaluate the energy-momentum of the gravitational field of a Schwarzschild black hole of mass M in the frame of a moving observer that asymptotically undergoes a Lorentz boost. The analysis is carried out in the framework of the teleparallel equivalent of general relativity (TEGR). We find that the total expression for the energy-momentum of the gravitational field is similar to the usual relativistic expression for the energy-momentum four-vector of a particle of inertial mass M under a Lorentz boost in flat space-time. Moreover we conclude that if the observer accelerates with respect to the black hole he will experience gravitational energy radiation, in similarity to the expected radiation of an accelerated charged particle in electrodynamics. We show that the increase of the mass of the black hole by the usual factor gamma as observed in the moving frame, which is a typical feature of special relativity if the black hole is considered asymptotically as a body of mass M, is due to gravitational radiation.