Radiation reaction in curved space-time: local method

Abstract

Although consensus seems to exist about the validity of equations accounting for radiation reaction in curved space-time, their previous derivations were criticized recently as not fully satisfactory: some ambiguities were noticed in the procedure of integration of the field momentum over the tube surrounding the world-line. To avoid these problems we suggest a purely local derivation dealing with the field quantities defined only {\em on the world-line}. We consider point particle interacting with scalar, vector (electromagnetic) and linearized gravitational fields in the (generally non-vacuum) curved space-time. To properly renormalize the self-action in the gravitational case, we use a manifestly reparameterization-invariant formulation of the theory. Scalar and vector divergences are shown to cancel for a certain ratio of the corresponding charges. We also report on a modest progress in extending the results for the gravitational radiation reaction to the case of non-vacuum background.Comment: 10 pages, ws-procs9x6, published in "Gravitation and Astrophysics", Proceedings of the VII Asia-Pacific International Conference National Central University, Taiwan 23 - 26 November 2005, ed. J.M. Nester, C.-M. Chen, J.-P. Hsu. World Scientific, 2006, pp. 345-35