Tachyon Back Reaction on $d = 2$ String Black Hole

TL;DR

This paper presents a static solution in two-dimensional string theory that includes tachyon back reaction, revealing horizon splitting and new singularities, with extensions and potential methods to resolve these issues.

Contribution

It introduces a novel static solution with tachyon back reaction in 2D string theory, analyzing horizon structure and singularities, and proposes time-dependent extensions and singularity removal strategies.

Findings

Horizon splitting into two resembling Reissner-Nordstrom black holes

Development of new singularities at horizons due to tachyon back reaction

Persistence of these features even with nonzero tachyon potential

Abstract

We describe a static solution for $d = 2$ critical string theory including the tachyon $T$ but with its potential $V (T)$ set to zero. This solution thus incorporates tachyon back reaction and, when $T = 0$, reduces to the black hole solution. When $T \neq 0$ we find that (1) the Schwarzschild horizon of the above black hole splits into two, resembling Reissner-Nordstrom horizons and (2) the curvature scalar develops new singularities at the horizons. We show that these features will persist even when $V (T)$ is nonzero. We present a time dependent extension of our static solution and discuss some possible methods for removing the above singularities.