Stationary bound-state scalar configurations supported by rapidly-spinning exotic compact objects

Abstract

Some quantum-gravity theories suggest that the absorbing horizon of a classical black hole should be replaced by a reflective surface which is located a microscopic distance above the would-be classical horizon. Instead of an absorbing black hole, the resulting horizonless spacetime describes a reflective exotic compact object. Motivated by this intriguing prediction, in the present paper we explore the physical properties of exotic compact objects which are linearly coupled to stationary bound-state massive scalar field configurations. In particular, solving the Klein-Gordon wave equation for a stationary scalar field of proper mass $\mu$ and spheroidal harmonic indices $(l,m)$ in the background of a rapidly-rotating exotic compact object of mass $M$ and angular momentum $J=Ma$, we derive a compact analytical formula for the {\it discrete} radii $\{r_{\text{c}}(\mu ,l,m,M,a;n)\}$ of the exotic compact objects which can support the stationary bound-state massive scalar field configurations. We confirm our analytical results by direct numerical computations.

11 pages. arXiv admin note: text overlap with arXiv:1704.05856

References in corpus (25)

• Ultralight scalars as cosmological dark matter
• Instability of the massive Klein-Gordon field on the Kerr spacetime
• The fuzzball proposal for black holes
• Light rings as observational evidence for event horizons: long-lived modes, ergoregions and nonlinear instabilities of ultracompact objects
• How to tell a gravastar from a black hole
• Superradiant instabilities in astrophysical systems
• Kerr-Newman scalar clouds
• Weak Cosmic Censorship: As Strong as Ever
• Kerr-Newman black holes with stationary charged scalar clouds
• Tidal deformability and I-Love-Q relations for gravastars with polytropic thin shells
• A new spin on black hole hair
• Non-linear Q-clouds around Kerr black holes
• Scalarized Hairy Black Holes
• Myers-Perry black holes with scalar hair and a mass gap
• Stability of highly-charged Reissner-Nordström black holes to charged scalar perturbations
• The large-mass limit of cloudy black holes
• Extremal Kerr-Newman black holes with extremely short charged scalar hair
• Rotating black holes can have short bristles
• Myers-Perry black holes with scalar hair and a mass gap: unequal spins
• Wiggly tails: a gravitational wave signature of massive fields around black holes
• A no-short scalar hair theorem for rotating Kerr black holes
• Marginal scalar and Proca clouds around Reissner-Nordström black holes
• Analytic treatment of the system of a Kerr-Newman black hole and a charged massive scalar field
• Eigenvalue spectrum of the spheroidal harmonics: A uniform asymptotic analysis
• Analytical study of superradiant instability for five-dimensional Kerr-Gödel black hole

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• On the instability of ultracompact horizonless spacetimes
• The longlived charged massive scalar field in the higher-dimensional Reissner--Nordström spacetime
• Isotropic compact stars in 4D Einstein-Gauss-Bonnet gravity
• Scalar field condensation behaviors around reflecting shells in Anti-de Sitter spacetimes
• Analytic study of self-gravitating polytropic spheres with light rings
• Lower bound on the compactness of isotropic ultra-compact objects
• No hair for spherically symmetric neutral reflecting stars: nonminimally coupled massive scalar fields
• Ultra-spinning exotic compact objects supporting static massless scalar field configurations
• Spontaneous scalarization of Gauss-Bonnet black holes surrounded by massive scalar fields
• Scalarization of compact stars in the scalar-Gauss-Bonnet gravity
• Analytical Study of a Kerr-Sen Black Hole and a Charged Massive Scalar Field
• Analytical investigations on formations of hairy neutral reflecting shells in the scalar-Gauss-Bonnet gravity
• Quasibound states of the Dirac field in Schwarzschild and Reissner-Nordström black hole backgrounds
• No hair theorem for bound-state massless static scalar fields outside horizonless Neumann compact stars
• On instabilities of stationary scalar field configurations supported by reflecting compact stars