Conformally Exact Black Hole Perturbed by a Marginal Operator

TL;DR

This paper investigates how adding a marginal operator, specifically a tachyon field, affects the conformal invariance and geometry of gauged WZW models, revealing a critical dimension at d=2 where the effects differ.

Contribution

It introduces a detailed analysis of tachyon condensation effects in gauged WZW models, highlighting the critical role of the dimension in conformal invariance modifications.

Findings

For d>2, tachyon condensation modifies the metric.

For d≤2, the metric remains unchanged.

Higher order corrections are necessary for full conformal invariance.

Abstract

We have examined effective theory induced by gauged WZW models, in which the tachyon field is added as a marginal operator. Due to this operator added, we must further add the higher order corrections, which modifies the original configuration, to make the theory full-conformally invariant. It has been found that 2d is a critical dimension in the sense that the metric obtained from gauged WZW is modified by the tachyon condensation for $d>2$, but not for $d\le 2$.