A Toy Model of Closed String Tachyon Effective Action

TL;DR

This paper introduces a simplified model for the effective action of closed string tachyons, demonstrating exact solutions in specific backgrounds and applying it to two-dimensional bosonic string theory.

Contribution

It presents a toy model of the closed string tachyon effective action with exact solutions, including applications to two-dimensional bosonic string theory.

Findings

Exact solutions with marginal tachyon profiles in specific backgrounds

Model remains valid even with backreaction considerations

Application to two-dimensional bosonic string theory

Abstract

In this paper we propose the toy model of the closed string tachyon effective action that has marginal tachyon profile as its exact solution in case of constant or linear dilaton background. Then we will apply this model for description of two dimensional bosonic string theory. We will find that the background configuration with the spatial dependent linear dilaton, flat spacetime metric and marginal tachyon profile is the exact solution of our model even if we take into account backreaction of tachyon on dilaton and metric.