New Superstrata from Three-Dimensional Supergravity

TL;DR

This paper introduces a new two-parameter family of smooth, supersymmetric microstate geometries called generalized superstrata in three-dimensional gauged supergravity, extending previous non-supersymmetric solutions and providing analytic proofs of their supersymmetry.

Contribution

It proves the supersymmetry of a new two-parameter family of generalized superstrata and derives explicit smooth solutions, expanding the understanding of microstate geometries in supergravity.

Findings

Established supersymmetry of the two-parameter family of solutions

Derived an explicit analytic solution with enhanced $SO(3)$ symmetry

Confirmed non-supersymmetry of other known microstrata families

Abstract

We find a two-parameter family of {\it generalized superstrata} that emerge as smooth, supersymmetric solutions in three-dimensional gauged supergravity coupled to additional scalar fields. This new family of generalized superstrata are smooth microstate geometries and may be thought of as supersymmetric Coulomb-branch extensions of the original superstrata in which the underlying supertube undergoes an elliptical deformation. These solutions had already been obtained numerically, and as series solutions, to the equations of motion, and some of them were conjectured to be supersymmetric. Here we prove the supersymmetry of an entire two-parameter family and we obtain a highly non-trivial analytic and smooth solution for a one-parameter limit in which the global symmetry of the metric is enhanced to $SO(3)$. We also confirm that the other known families of microstrata are {\it not} supersymmetric. We conclude with a cursory analysis of some of the singular brane distributions that can be accessed from three-dimensional gauged supergravity while preserving the same supersymmetries as the superstratum, and therefore of the three-charge black hole.