Dimensional reduction of BPS attractors in AdS gauged supergravities

TL;DR

The paper shows that BPS attractors of black strings and black holes in gauged supergravities with nontrivial scalar potentials, whose near-horizon geometries are $AdS_{2,3} \times \Sigma^{2,3}$, can be related across dimensions via dimensional reduction in a way that preserves supersymmetry and yields physically meaningful, though non-Maximally Symmetric, lower-dimensional vacua. It provides a concrete 5d→4d map between Benini-Bobev black strings and Cacciatori-Klemm black holes, including exact near-horizon matching and a string-theoretic embedding in type IIB on $AdS_5 \times S^5$, with the field theory Cardy formula reproducing the black hole entropy for horizons of arbitrary genus. The analysis is extended to 6d→5d reductions, exploring different compactification directions (AdS$_3$ or $S^3$) and demonstrating that the general mechanism of generating runaway lower-dimensional theories from higher-dimensional AdS vacua is robust. These results offer a unified, higher-dimensional perspective on attractor geometries with runaway asymptotics and provide a concrete bridge to microscopic (string/field theory) descriptions of the corresponding black objects.

Abstract

We relate across dimensions BPS attractors of black strings and black holes of various topology in gauged supergravities with nontrivial scalar potential. The attractors are of the form AdS$_{2, 3} \times Σ^{2, 3}$ in 4, 5, and 6 dimensions, and can be generalized to some higher dimensional analogs. Even though the attractor geometries admit standard Kaluza-Klein and Scherk-Schwarz reductions, their asymptotic AdS spaces in general do not. The resulting lower dimensional objects are black holes with runaway asymptotics in supergravity theories with no maximally symmetric vacua. Such classes of solutions are already known to exist in literature, and results here suggest an interpretation in terms of their higher-dimensional origin that often has a full string theory embedding. In a particular relevant example, the relation between 5d Benini-Bobev black strings arXiv:1302.4451 and a class of 4d Cacciatori-Klemm black holes arXiv:0911.4926 is worked out in full detail, providing a type IIB and dual field theory description of the latter solutions. As a consistency check, the Cardy formula for the field theory is shown to match the Bekenstein-Hawking entropy for horizon topology of any genus.