Upper bounds on the compactness at the innermost light ring of anisotropic horizonless spheres
arXiv:2006.02618 · doi:10.1140/epjc/s10052-020-8358-z
Abstract
In the background of isotropic horizonless spheres, Hod recently provided an analytical proof of a bound on the compactness at the innermost light ring with the dominant energy and non-negative trace conditions. In this work, we extend the discussion of isotropic spheres to anisotropic spheres. With the same dominant energy and non-negative trace conditions, we prove that Hod's bound also holds in the case of anisotropic horizonless spheres.
arXiv comment7 pages
References in corpus (32)
- Geodesic stability, Lyapunov exponents and quasinormal modes
- Light ring stability in ultra-compact objects
- Quasinormal-mode spectrum of Kerr black holes and its geometric interpretation
- Connection between black-hole quasinormal modes and lensing in the strong deflection limit
- Fundamental photon orbits: black hole shadows and spacetime instabilities
- Slowly Decaying Waves on Spherically Symmetric Spacetimes and an Instability of Ultracompact Neutron Stars
- Universal Bound on Dynamical Relaxation Times and Black-Hole Quasinormal Ringing
- The Quasinormal Mode Spectrum of a Kerr Black Hole in the Eikonal Limit
- Black-hole quasinormal resonances: Wave analysis versus a geometric-optics approximation
- Hairy Black Holes and Null Circular Geodesics
- Does the black hole shadow probe the event horizon geometry?
- Black holes have no short hair
- Unstable circular null geodesics of static spherically symmetric black holes, Regge poles and quasinormal frequencies
- Upper bound on the radii of black-hole photonspheres
- General relativistic polytropes with a repulsive cosmological constant
- Spherical null geodesics of rotating Kerr black holes
- The fastest way to circle a black hole
- Resonance spectrum of near-extremal Kerr black holes in the eikonal limit
- Gravitational instability of polytropic spheres containing region of trapped null geodesics: a possible explanation of central supermassive black holes in galactic halos
- Resonance and absorption spectra of the Schwarzschild black hole for massive scalar perturbations: a complex angular momentum analysis
- A no-short scalar hair theorem for rotating Kerr black holes
- Polytropic spheres containing regions of trapped null geodesics
- Black Hole Shadows and Invariant Phase Space Structures
- Photon spheres in Einstein and Einstein-Gauss-Bonnet theories and circular null geodesics in axially-symmetric spacetimes
- Self-gravitating field configurations: The role of the energy-momentum trace
- On instabilities of scalar hairy regular compact reflecting stars
- Hair mass bound in the black hole with nonzero cosmological constants
- Analytic study of self-gravitating polytropic spheres with light rings
- Lower bound on the compactness of isotropic ultra-compact objects
- Upper bound on the gravitational masses of stable spatially regular charged compact objects
- Hairy mass bound in the Einstein-Born-Infeld black hole
- Fermat's principle in black-hole spacetimes