Boosting Away Singularities from Conformal String Backgrounds

TL;DR

This paper demonstrates how $O(d,d)$ transformations can be used to remove singularities in string backgrounds, exemplified by transforming a model into a singularity-free configuration through boosts in an extended dimension.

Contribution

It introduces a method using $O(d,d)$ boosts to eliminate singularities in string cosmological and black-hole backgrounds, extending previous work.

Findings

Singularities can be removed via $O(d,d)$ transformations.

A specific model was made singularity-free using $O(3,3)$ boosts.

The approach generalizes previous techniques for smoothing string backgrounds.

Abstract

Generalizing our previous work, we show how $O(d,d)$ transformations can be used to "boost away" in new dimensions the physical singularities that occur generically in cosmological and/or black-hole string backgrounds. As an example, we show how a recent model by Nappi and Witten can be made singularity-free via $O(3,3)$ boosts involving a fifth dimension.