Superradiant instabilities in the Kerr-mirror and Kerr-AdS black holes with Robin boundary conditions

Abstract

It has been recently observed that a scalar field with Robin boundary conditions (RBCs) can trigger both a superradiant and a bulk instability for a BTZ black hole (BH). To understand the generality and scrutinize the origin of this behavior, we consider here the superradiant instability of a Kerr BH confined either in a mirror-like cavity or in AdS space, triggered also by a scalar field with RBCs. These boundary conditions are the most general ones that ensure the cavity/AdS space is an isolated system, and include, as a particular case, the commonly considered Dirichlet boundary conditions (DBCs). Whereas the superradiant modes for some RBCs differ only mildly from the ones with DBCs, in both cases we find that as we vary the RBCs, the imaginary part of the frequency may attain arbitrarily large positive values. We interpret this growth as being sourced by a bulk instability of both confined geometries when certain RBCs are imposed to either the mirror-like cavity or the AdS boundary, rather than by energy extraction from the BH, in analogy with the BTZ behavior.

arXiv comment10 pages, 6 figures; v2: discussion of Kerr-mirror case revised and expanded

References in corpus (27)

• Instability of the massive Klein-Gordon field on the Kerr spacetime
• On weakly turbulent instability of anti-de Sitter space
• The black hole bomb and superradiant instabilities
• Superradiant Instability and Backreaction of Massive Vector Fields around Kerr Black Holes
• Black holes as particle detectors: evolution of superradiant instabilities
• Small Kerr-anti-de Sitter black holes are unstable
• Superradiant instabilities of rotating black holes in the time domain
• Explosion and final state of an unstable Reissner-Nordstrom black hole
• Floating and sinking: the imprint of massive scalars around rotating black holes
• Stability and quasinormal modes of the massive scalar field around Kerr black holes
• On the instability regime of the rotating Kerr spacetime to massive scalar perturbations
• Nonlinear Evolution and Final Fate of Charged Anti-de Sitter Black Hole Superradiant Instability
• Kerr black holes with synchronised hair: an analytic model and dynamical formation
• The extremal black hole bomb
• Exponentially growing finite energy solutions for the Klein-Gordon equation on sub-extremal Kerr spacetimes
• Dynamical formation of a Reissner-Nordström black hole with scalar hair in a cavity
• Massive scalar field instability in Kerr spacetime
• The superradiant instability regime of the spinning Kerr black hole
• Instability of Flat Space Enclosed in a Cavity
• Black Hole Superradiance in Dynamical Spacetime
• Hadamard states for a scalar field in anti-de Sitter spacetime with arbitrary boundary conditions
• Maxwell perturbations on Kerr-anti-de Sitter: quasinormal modes, superradiant instabilities and vector clouds
• Onset of superradiant instabilities in the composed Kerr-black-hole-mirror bomb
• Superradiance in the BTZ black hole with Robin boundary conditions
• Stationary scalar clouds around a BTZ black hole
• Maxwell perturbations on asymptotically anti-de Sitter spacetimes: Generic boundary conditions and a new branch of quasinormal modes
• The spinning Kerr-black-hole-mirror bomb: A lower bound on the radius of the reflecting mirror

Cited by in corpus (15)

• Superradiant instability of charged scalar fields in higher-dimensional Reissner-Nordström-de Sitter black holes
• Weak Cosmic Censorship with Pressure and Volume in Charged Anti-de Sitter Black Hole under Charged Scalar Field
• Charged black hole bombs in a Minkowski cavity
• Superradiant stability of the Kerr black holes
• Scalar condensation behaviors around regular Neuman reflecting stars
• Superradiance of massive scalar particles around rotating regular black holes
• Scalar Perturbation Around Rotating Regular Black Hole: Superradiance Instability and Quasinormal Modes
• Superradiance of a Global Monopole in Reissner-Nordström(-AdS) Space-time
• Superradiant stability of five and six-dimensional extremal Reissner-Nordstrom black holes
• No black hole bomb for D-dimensional extremal Reissner-Nordstrom black holes under charged massive scalar perturbation
• Exotic compact object behavior in black hole analogues
• No-go theorem for static boson stars with negative cosmological constants
• Nonlinear Evolution of unstable Charged de Sitter Black Holes with Hyperboloidal Formalism
• Charged black holes in de Sitter space: superradiant amplification of charged scalar waves and resonant hyperradiation
• $\ell$-Boson stars in anti-de Sitter spacetime