Winding tachyons in BTZ

TL;DR

This paper investigates winding tachyons in a BTZ black hole background supported by NS-NS flux, revealing their non-localized nature due to B-field effects and exploring implications for spacetime understanding in string theory.

Contribution

It provides a detailed analysis of the string spectrum on BTZ black holes with flux, highlighting the conditions for tachyon appearance and their non-localization caused by B-field effects.

Findings

Winding tachyons appear when the horizon is below the string scale.

The tachyon is not localized near the string-scale spatial circle due to B-field effects.

Discussion of the relation to Milne orbifold near the singularity.

Abstract

Analysing closed string tachyon condensation will improve our understanding of spacetime in string theory. We study the string spectrum on a BTZ black hole spacetime supported by NS-NS flux, which provides a calculable example where we would expect to find a quasi-localised tachyon. We find that there is a winding tachyon when the black hole horizon is smaller than the string scale, as expected. However, due to effects of the NS-NS B field, this tachyon is not localised in the region where the spatial circle is string scale. We also discuss the relation to the Milne orbifold in the limit near the singularity.