Multi-centered D1-D5 solutions at finite B-moduli

TL;DR

This paper investigates how two-centered D1-D5 systems on T^4 behave when a B-field moduli is introduced, revealing that supersymmetric bound states become metastable at finite B-moduli, with implications for the fuzzball proposal.

Contribution

It demonstrates that finite B-moduli cause marginal bound states to become metastable, breaking supersymmetry, especially when charges are unequal, and shows this effect is independent of string coupling.

Findings

Marginal bound states become metastable at finite B-moduli.

Supersymmetry breaking effects diminish when charges are comparable.

The effect is independent of string coupling, applicable at weak coupling.

Abstract

We study the fate of two-centered D1-D5 systems on T^4 away from the singular supergravity point in the moduli space. We do this by considering a background D1-D5 black hole with a self-dual B-field moduli turned on and treating the second center in the probe limit in this background. We find that in general marginal bound states at zero moduli become metastable at finite B-moduli, demonstrating a breaking of supersymmetry. However, we also find evidence that when the charges of both centers are comparable, the effects of supersymmetry breaking become negligible. We show that this effect is independent of string coupling and thus it should be possible to reproduce this in the CFT at weak coupling. We comment on the implications for the fuzzball proposal.