Related papers: Black Hole Spindown by Light Bosons
The quantum entropy of the Kerr black hole arising from gravitational perturbation is investigated by using Null tetrad and \'t Hooft\'s brick-wall model. It is shown that effect of the graviton\'s spins on the subleading correction is…
The superradiant instabilities of Kerr-Newman black holes with charged or uncharged massive spin-0 fields are calculated analytically to the next-to-leading order in the limit of $\alpha\sim r_g \mu \ll 1$. A missing factor of $1/2$ in the…
Discerning the likelihood of the so-called runaway instability of thick accretion disks orbiting black holes is an important issue for most models of cosmic gamma-ray bursts. To this aim we investigate this phenomenon by means of…
The current early stage in the investigation of the stability of the Kerr metric is characterized by the study of appropriate model problems. Particularly interesting is the problem of the stability of the solutions of the Klein-Gordon…
We evolve a binary black hole system bearing a mass ratio of $q=m_1/m_2=2/3$ and individual spins of $S^z_1/m_1^2=0.95$ and $S^z_2/m_2^2=-0.95$ in a configuration where the large black hole has its spin antialigned with the orbital angular…
It has recently been proved numerically that spinning black holes in Einstein-scalar theories which are characterized by a non-minimal negative coupling of the scalar field to the Gauss-Bonnet invariant of the curved spacetime may develop…
An energy $E=\omega J$ is derived for gravitational spin-orbit coupling by frame-dragging $\omega$ acting on angular momentum $J$. This interaction defines a no-boundary mechanism for linear acceleration of magnetized matter along the axis…
A solution of Einstein's vacuum field equations that describes a boosted Kerr black hole relative to an asymptotic Lorentz frame at the future null infinity is derived. The solution has three parameters (mass, rotation and boost) and…
We perform the stability analysis of the Kerr black hole in the Einstein-Chern-Simons-Scalar theory with quadratic scalar coupling. For positive coupling parameter ($\alpha>0$), we introduce the (2+1)-dimensional hyperboloidal foliation…
The tidal acceleration experienced by an object at the event horizon of a black hole decreases as one over the square of the black hole's mass. As such there is a maximum mass at which a black hole can tidally disrupt an object outside of…
It is well known that celestial bodies tend to be spherical due to gravity and that rotation produces deviations from this sphericity. We discuss what is known and expected about the shape of black holes' horizons from their formation to…
Recent X-ray timing and spectral observations of black hole binaries in outburst have redefined methods for investigating the properties of Galactic black holes and the physics of accretion flows. High-frequency X-ray QPOs in 5 systems…
Due to coherent superradiant amplification, massive bosonic fields can trigger an instability in spinning black holes, tapping their energy and angular momentum and forming macroscopic Bose-Einstein condensates around them. This phenomenon…
A co-rotating bosonic field interacting with a spinning Kerr black hole can extract rotational energy and angular momentum from the hole. This intriguing phenomenon is known as superradiant scattering. As pointed out by Press and Teukolsky,…
We show that the horizon instability of the extremal Kerr black hole is associated with a singular branch point in the Green function at the superradiant bound frequency. We study generic initial data supported away from the horizon and…
Massive spin-2 fields, which arise in proposed extensions of the standard model of particle physics and general relativity, give rise to a superradiant instability around spinning black holes. We study the nonlinear evolution of this…
We consider a subset of the physical processes that determine the spin j = a/M of astrophysical black holes. These include: (1) Initial conditions. Recent models suggest that the collapse of supermassive stars are likely to produce black…
Most extreme-mass-ratio-inspirals of small compact objects into supermassive black holes end with a fast plunge from an eccentric last stable orbit. For rapidly rotating black holes such fast plunges may be studied in the context of the…
We examine the dynamics of particles around a rotating regular black hole. In particular we focus on the effects of the characteristic length parameter of the spinning black hole on the motion of the particles by solving the equation of…
We regard binary black hole (BBH) merger as a map from a simple initial state (two Kerr black holes, with dimensionless spins {\bf a} and {\bf b}) to a simple final state (a Kerr black hole with mass m, dimensionless spin {\bf s}, and kick…