Hair on non-extremal D1-D5 bound states

TL;DR

This paper constructs a smooth, normalizable linearized perturbation carrying left-moving momentum on non-extremal D1-D5 geometries within a specific supergravity truncation, advancing understanding of microstate geometries.

Contribution

It introduces a new perturbation in a truncated supergravity model that is smooth and normalizable, extending the analysis of D1-D5 bound states.

Findings

Perturbation is smooth everywhere.

Perturbation is normalizable.

Constructed by matching inner and outer solutions.

Abstract

We consider a truncation of type IIB supergravity on four-torus where in addition to the Ramond-Ramond 2-form field, the Ramond-Ramond axion (w) and the NS-NS 2-form field (B) are also retained. In the (w, B) sector we construct a linearised perturbation carrying only left moving momentum on two-charge non-extremal D1-D5 geometries of Jejjala, Madden, Ross and Titchener. The perturbation is found to be smooth everywhere and normalizable. It is constructed by matching to leading order solutions of the perturbation equations in the inner and outer regions of the geometry.