Higher-dimensional Rotating Charged Black Holes

TL;DR

The paper develops and applies the blackfold approach to higher-dimensional rotating black holes with electric charges and string dipoles in theories with a dilaton and $q$-form fields, covering regimes from ultraspinning to near-extremality. By formulating intrinsic fluid dynamics with $0$- and $1$-brane currents and coupling to extrinsic embedding, it constructs explicit charged blackfolds (disks, even-balls, odd-spheres) and string-dipole blackfolds (annuli, solid rings, and prolate rings), deriving their thermodynamics, first laws, and Smarr relations. It benchmarks these analytic constructions against known exact solutions in certain limits (notably Kaluza-Klein cases) and uncovers new instabilities near extremality, as well as topological constraints on dipole hair. The results broaden the landscape of higher-dimensional charged and dipole black holes, reveal regimes where near-extremal charges balance tension with rotation, and suggest robust predictions for horizon topology and stability in the blackfold regime.

Abstract

Using the blackfold approach, we study new classes of higher-dimensional rotating black holes with electric charges and string dipoles, in theories of gravity coupled to a 2-form or 3-form field strength and to a dilaton with arbitrary coupling. The method allows to describe not only black holes with large angular momenta, but also other regimes that include charged black holes near extremality with slow rotation. We construct explicit examples of electric rotating black holes of dilatonic and non-dilatonic Einstein-Maxwell theory, with horizons of spherical and non-spherical topology. We also find new families of solutions with string dipoles, including a new class of prolate black rings. Whenever there are exact solutions that we can compare to, their properties in the appropriate regime are reproduced precisely by our solutions. The analysis of blackfolds with string charges requires the formulation of the dynamics of anisotropic fluids with conserved string-number currents, which is new, and is carried out in detail for perfect fluids. Finally, our results indicate new instabilities of near-extremal, slowly rotating charged black holes, and motivate conjectures about topological constraints on dipole hair.