Intersecting Attractors

TL;DR

This paper uses entropy formalism to analyze the near-horizon geometry of extremal black p-brane intersections in higher-dimensional supergravities, linking attractor mechanisms to entropy and dual CFT properties.

Contribution

It introduces a novel entropy function approach for intersecting black branes in D>5 supergravities, connecting scalar flows, U-duality invariants, and boundary CFT central charges.

Findings

Entropy function reproduces Bekenstein-Hawking area law.

Active scalars fixed at minima of effective potential.

Explicit solutions for black hole and black string intersections in D=6,7,8.

Abstract

We apply the entropy formalism to the study of the near-horizon geometry of extremal black p-brane intersections in D>5 dimensional supergravities. The scalar flow towards the horizon is described in terms an effective potential given by the superposition of the kinetic energies of all the forms under which the brane is charged. At the horizon active scalars get fixed to the minima of the effective potential and the entropy function is given in terms of U-duality invariants built entirely out of the black p-brane charges. The resulting entropy function reproduces the central charges of the dual boundary CFT and gives rise to a Bekenstein-Hawking like area law. The results are illustrated in the case of black holes and black string intersections in D=6, 7, 8 supergravities where the effective potentials, attractor equations, moduli spaces and entropy/central charges are worked out in full detail.