Eur. Phys. J. C (2006) 48: 291-301
https://doi.org/10.1140/epjc/s2006-02553-3

Theoretical Physics

IR renormalization of general effective actions and Hawking flux in 2D gravity theories

Institut für Theoretische Physik, Technische Universität Wien, Wiedner Hauptstr. 8–10, 1040, Wien, Austria

^* e-mail: hofmann@hep.itp.tuwien.ac.at

Received: 22 March 2006
Published online: 8 August 2006

Abstract

The infrared problem of the effective action in 2D is discussed in the framework of the covariant perturbation theory. The divergences are regularized by a mass and the leading term is evaluated up to the third order of perturbation theory. A summation scheme is proposed which isolates the divergences from the finite part of the series and results in a single term. The latter turns out to be equivalent to the coupling to a certain classical external field. This suggests renormalization by factorization.