Static and non-static quantum effects in two-dimensional dilaton gravity

TL;DR

This paper investigates quantum backreaction effects in two-dimensional dilaton gravity, revealing that certain quantum corrections do not induce black hole evaporation and can generate new singularities.

Contribution

It introduces the role of an $R^2$ term from one-loop effective action in two-dimensional dilaton gravity, analyzing its impact on black hole solutions and singularities.

Findings

The $R^2$ term does not affect Hawking radiation.

New singularities can form in time-dependent solutions.

Black hole structure persists despite quantum corrections.

Abstract

We study backreaction effects in two-dimensional dilaton gravity. The backreaction comes from an $R^2$ term which is a part of the one-loop effective action arising from massive scalar field quantization in a certain approximation. The peculiarity of this term is that it does not contribute to the Hawking radiation of the classical black hole solution of the field equations. In the static case we examine the horizon and the physical singularity of the new black hole solutions. Studying the possibility of time dependence we see the generation of a new singularity. The particular solution found still has the structure of a black hole, indicating that non-thermal effects cannot lead, at least in this approximation, to black hole evaporation.