Removing Singularities

TL;DR

This paper demonstrates that turning on gauge fields in certain string theory backgrounds can eliminate big bang/crunch singularities, with implications for wave reflection and the persistence of BTZ-like singularities.

Contribution

It introduces a family of quotient CFTs that remove curvature singularities via gauge fields, providing a new approach to singularity resolution in string theory.

Findings

Uncharged wavefunctions are fully reflected when big bang/crunch singularities are present.

Turning on gauge fields can remove these singularities in specific string backgrounds.

Extended BTZ-like singularities persist if U(1)_x remains compact.

Abstract

Big bang/crunch curvature singularities in exact CFT string backgrounds can be removed by turning on gauge fields. This is described within a family of {SL(2)xSU(2)xU(1)_x}/{U(1)xU(1)} quotient CFTs. Uncharged incoming wavefunctions from the ``whiskers'' of the extended universe can be fully reflected if and only if a big bang/crunch curvature singularity, from which they are scattered, exists. Extended BTZ-like singularities remain as long as U(1)_x is compact.