On the Black Hole Background of Two-Dimensional String Theory

TL;DR

This paper investigates the classical black hole background in two-dimensional string theory considering tachyon effects, finding that the only consistent solution is flat spacetime with a nontrivial dilaton when including terms up to second order in tachyon.

Contribution

It provides a detailed analysis of the black hole background in 2D string theory with tachyon effects, revealing the unique flat spacetime solution with a nontrivial dilaton.

Findings

The only consistent classical solution is flat spacetime with a nontrivial dilaton.

Including all terms up to second order in tachyon yields no black hole solutions.

The analysis clarifies the role of tachyon fields in 2D string theory backgrounds.

Abstract

The classical black hole background of two-dimensional string theory is examined after including the effect of the tachyon field. Keeping all terms upto $O(T^2)$, and making no other approximations, the only consistent classical solution to the resulting dilaton-graviton theory is found to be flat spacetime with a nontrivial dilaton.