Comments on String Dynamics in Six Dimensions

TL;DR

This paper analyzes the singularities in the moduli space of six-dimensional string compactifications with N=1 supersymmetry, focusing on massless particles and tensionless strings, and their role in phase transitions and connecting different vacua.

Contribution

It provides a detailed discussion of the nature of singularities in the moduli space, highlighting the role of tensionless strings and their connection to phase transitions in six-dimensional N=1 supersymmetric vacua.

Findings

Singularities arise from massless particles or tensionless strings.

Tensionless string points can indicate phase transitions.

These results unify known N=1 supersymmetric vacua in six dimensions.

Abstract

We discuss the singularities in the moduli space of string compactifications to six dimensions with $N=1$ supersymmetry. Such singularities arise from either massless particles or non-critical tensionless strings. The points with tensionless strings are sometimes phase transition points between different phases of the theory. These results appear to connect all known $N=1$ supersymmetric six-dimensional vacua.