Matrix Models and Nonperturbative String Propagation in Two-Dimensional Black Hole Backgrounds

TL;DR

This paper uses the $c=1$ matrix model to analyze the nonperturbative wavefunction of tachyon scattering in a two-dimensional black hole background, revealing a nonsingular behavior at the singularity and a novel end state.

Contribution

It identifies a specific quantity in the matrix model that describes the nonperturbative scattering wavefunction in 2D black hole backgrounds, showing it remains nonsingular at the singularity.

Findings

Nonperturbative wavefunction is nonsingular at the black hole singularity.

Wavefunction appears to end in the region behind the singularity.

Semiclassical picture is modified by nonperturbative effects.

Abstract

We identify a quantity in the $c=1$ matrix model which describes the wavefunction for physical scattering of a tachyon from a black hole of the two dimensional critical string theory. At the semiclassical level this quantity corresponds to the usual picture of a wave coming in from infinity, part of which enters the black hole becoming singular at the singularity, while the rest is scattered back to infinity, with nothing emerging from the whitehole. We find, however, that the exact nonperturbative wavefunction is nonsingular at the singularity and appears to end up in the asymptotic region ``behind'' the singularity.