papers

Publications (20)

hep-th2020

Black Ripples, Flowers and Dumbbells at large

David Licht, Raimon Luna, Ryotaku Suzuki

We explore the rich phase space of singly spinning (both neutral and charged) black hole solutions in the large limit. We find several 'bumpy' branches which are connected to m…

gr-qc2024

Quasinormal Modes in Modified Gravity using Physics-Informed Neural Networks

Raimon Luna, Daniela D. Doneva, José A. Font +2

In this paper, we apply a novel approach based on physics-informed neural networks to the computation of quasinormal modes of black hole solutions in modified gravity. In particula…

hep-th2017

Geometric polarization of plasmas and Love numbers of AdS black branes

Roberto Emparan, Alejandro Fernandez-Pique, Raimon Luna

We use AdS/CFT holography to study how a strongly-coupled plasma polarizes when the geometry where it resides is not flat. We compute the linear-response polarization coefficients,…

hep-th2016

Hydro-elastic Complementarity in Black Branes at large D

Roberto Emparan, Keisuke Izumi, Raimon Luna +2

We obtain the effective theory for the non-linear dynamics of black branes---both neutral and charged, in asymptotically flat or Anti-deSitter spacetimes---to leading order in the…

hep-th2023

Holographic duals of evaporating black holes

Roberto Emparan, Raimon Luna, Ryotaku Suzuki +2

We describe the dynamical evaporation of a black hole as the classical evolution in time of a black hole in an Anti-de Sitter braneworld. A bulk black hole whose horizon intersects…

hep-th2020

Entropy production and entropic attractors in black hole fusion and fission

Tomas Andrade, Roberto Emparan, Aron Jansen +3

We study how black hole entropy is generated and the role it plays in several highly dynamical processes: the decay of unstable black strings and ultraspinning black holes; the fus…

gr-qc2021

Addendum to "Strong cosmic censorship: The nonlinear story"

Raimon Luna, Miguel Zilhão, Vitor Cardoso +2

We clarify a number of issues that arise when extending the analysis of Strong Cosmic Censorship (SCC) to perturbations of highly charged Reissner-Nordström de Sitter (RNdS) space…

gr-qc2024

Solving the Teukolsky equation with physics-informed neural networks

Raimon Luna, Juan Calderón Bustillo, Juan José Seoane Martínez +2

We use physics-informed neural networks (PINNs) to compute the first quasi-normal modes of the Kerr geometry via the Teukolsky equation. This technique allows us to extract the com…

hep-th2023

Holographic collisions in large effective theory

Raimon Luna, Mikel Sanchez-Garitaonandia

We study collisions of Gaussian mass-density blobs in a holographic plasma, using a large effective theory, as a model for holographic shockwave collisions. The simplicity of t…

hep-th2020

Phases and Stability of Non-Uniform Black Strings

Roberto Emparan, Raimon Luna, Marina Martinez +2

We construct solutions of non-uniform black strings in dimensions from all the way up to , and investigate their thermodynamics and dynamical stability. O…

gr-qc2022

Kicks in charged black hole binaries

Raimon Luna, Gabriele Bozzola, Vitor Cardoso +2

We compute the emission of linear momentum (kicks) by both gravitational and electromagnetic radiation in fully general-relativistic numerical evolutions of quasi-circular charged…

gr-qc2019

Challenges to global solutions in Horndeski's theory

Laura Bernard, Luis Lehner, Raimon Luna

We explore the question of obtaining global solutions in Horndeski's theories of gravity. Towards this end, we study a relevant set of the theory and, by employing the Einstein fra…

gr-qc2024

A numerical-relativity surrogate model for hyperbolic encounters of black holes: challenges in parameter estimation

Joan Fontbuté, Tomas Andrade, Raimon Luna +5

We present a surrogate numerical-relativity model for close hyperbolic black-hole encounters with equal masses and spins aligned with the orbital momentum. Our model, generated in…

hep-th2022

Lattice Black Branes at Large

David Licht, Raimon Luna, Ryotaku Suzuki

We explore the phase space of non-uniform black branes compactified on oblique lattices with a large number of dimensions. We find the phase diagrams for different periodicities an…

hep-th2019

Black hole collisions, instabilities, and cosmic censorship violation at large D

Tomas Andrade, Roberto Emparan, David Licht +1

We study the evolution of black hole collisions and ultraspinning black hole instabilities in higher dimensions. These processes can be efficiently solved numerically in an effecti…

hep-th2019

Cosmic censorship violation in black hole collisions in higher dimensions

Tomas Andrade, Roberto Emparan, David Licht +1

We argue that cosmic censorship is violated in the collision of two black holes in high spacetime dimension D when the initial total angular momentum is sufficiently large. The two…

gr-qc2024

Numerical relativity surrogate models for exotic compact objects: the case of head-on mergers of equal-mass Proca stars

Raimon Luna, Miquel Llorens-Monteagudo, Ana Lorenzo-Medina +6

We present several high-accuracy surrogate models for gravitational-wave signals from equal-mass head-on mergers of Proca stars, computed through the Newman-Penrose scalar .…

astro-ph.HE2025

Proto-neutron star oscillations including accretion flows

Dimitra Tseneklidou, Raimon Luna, Pablo Cerdá-Durán +1

The gravitational wave signature from core-collapse supernovae (CCSNe) is dominated by quadrupolar oscillation modes of the newly born proto-neutron star (PNS), and could be detect…

gr-qc2019

Strong cosmic censorship: The nonlinear story

Raimon Luna, Miguel Zilhão, Vitor Cardoso +2

A satisfactory formulation of the laws of physics entails that the future evolution of a physical system should be determined from appropriate initial conditions. The existence of…

gr-qc2019

Black holes, gravitational waves and fundamental physics: a roadmap

Leor Barack, Vitor Cardoso, Samaya Nissanke +203

The grand challenges of contemporary fundamental physics---dark matter, dark energy, vacuum energy, inflation and early universe cosmology, singularities and the hierarchy problem-…