N=8 non-BPS Attractors, Fixed Scalars and Magic Supergravities

TL;DR

This paper investigates the stability and spectrum of non-BPS black hole solutions in N=8 supergravity, linking them to N=2 magic supergravities and revealing degeneracy patterns in their spectra.

Contribution

It provides a detailed analysis of the Hessian matrix at non-BPS critical points in N=8 supergravity and relates these to N=2 magic supergravities, uncovering spectral degeneracies.

Findings

Agreement with known degeneracy splitting in N=2 non-BPS spectra

Relation of non-BPS critical points to N=2 magic supergravities

Identification of critical points with vanishing central charge

Abstract

We analyze the Hessian matrix of the black hole potential of N=8, d=4 supergravity, and determine its rank at non-BPS critical points, relating the resulting spectrum to non-BPS solutions (with non-vanishing central charge) of N=2, d=4 magic supergravities and their ``mirror'' duals. We find agreement with the known degeneracy splitting of N=2 non-BPS spectrum of generic special Kahler geometries with cubic holomorphic prepotential. We also relate non-BPS critical points with vanishing central charge in N=2 magic supergravities to a particular reduction of the N=8, 1/8-BPS critical points.