Photon acceleration by gravitational waves

The Hamiltonian theory of the photon acceleration has been generalized for the case of electromagnetic wavepackets moving in space and time varying gravitational fields. It is shown that due to nearly equal phase velocities of the photons and gravitational waves;there appears a significant frequency shift. Such an efficient mechanism for the photon acceleration can eventually provide an alternative explanation for the observed gamma-ray bursts, Furthermore, it is also found that in the limiting case of a static gravitational field, the newly derived equations provide a simple and elegant description of the well-known gravitational redshift and gravitational lens. In more general terms, the present theory provides a novel coupling mechanism between the electromagnetic and gravitational waves. (C) 1998 Elsevier Science B.V.