activity
20242026
collaborators

9 papers

gr-qc2026

Black Hole Ringdown Nonlinearities in the Large-D Limit

Roberto Emparan, Amanda Green-Salinas, David Pereñiguez +1

We initiate the study of nonlinear effects in the ringdown phase of black hole mergers using the effective theory of black hole dynamics in the large-D limit. This framework offers…

hep-th2026

General Effective Theories of Black Holes in the Large D Limit

Roberto Emparan, Jordi Rafecas-Ventosa, Benson Way

We derive the general form of the effective equations governing black hole dynamics in the limit of a large number of dimensions . These split into a universal \emph{soap-bubble…

hep-th2025

Branes and Antibranes in AdS: The Impossible States in the CFT Gap

Roberto Emparan, Pierre Heidmann

We construct a new family of type IIB supergravity solutions corresponding to states of the D1-D5-P-KKm system that carry the same charges and energy as the non-extremal four-charg…

hep-th2025

Novel black saddles for 5d gravitational indices and the index enigma

Jan Boruch, Roberto Emparan, Luca V. Iliesiu +1

We construct a series of novel Euclidean multi-black-hole, black ring, black Saturn, and black lens solutions to supergravity that contribute as saddle-points to the grav…

hep-th2025

Quantum Transparency of Near-extremal Black Holes

Roberto Emparan, Stefano Trezzi

We investigate the scattering of electromagnetic and gravitational waves off a Reissner-Nordström black hole in the low-temperature regime where the near-horizon throat experience…

hep-th2025

The gravitational index of 5d black holes and black strings

Jan Boruch, Roberto Emparan, Luca V. Iliesiu +1

The supersymmetric index of 5d black strings and spinning black holes in M-theory is related to that of 4d black holes in type IIA supergravity when both theories are compactified…