On exact solutions and singularities in string theory

TL;DR

This paper introduces two novel classes of exact solutions in string theory, including a fundamental string with a vanishing coupling near singularities and hybrid solutions, highlighting persistent curvature singularities.

Contribution

The paper presents new exact solutions beyond standard types, expanding the landscape of string theory solutions with detailed analysis of their singularities.

Findings

Fundamental string solutions with vanishing coupling near singularities.

Hybrid solutions combining plane wave and gauged WZW features.

Singularities may persist despite new solution classes.

Abstract

We construct two new classes of exact solutions to string theory which are not of the standard plane wave or gauged WZW type. Many of these solutions have curvature singularities. The first class includes the fundamental string solution, for which the string coupling vanishes near the singularity. This suggests that the singularity may not be removed by quantum corrections. The second class consists of hybrids of plane wave and gauged WZW solutions. We discuss a four dimensional example in detail.