Related papers: Black/White hole radiation from dispersive theorie…
The work on black holes immersed in external fields is reviewed in both test-field approximation and within exact solutions. In particular we pay attention to the effect of the expulsion of the flux of external fields across charged and…
Optical field fluctuations in self-defocusing media can be described in terms of sound waves in a 2D photon-fluid. It is shown that, while the background fluid couples with the usual flat metric, sound-like waves experience an effective…
We construct four-dimensional gravity theories that resolve the Schwarzschild singularity and enable dynamical studies of nonsingular gravitational collapse. The construction employs a class of nonpolynomial curvature invariants that…
We apply the ADM 3+1 formalism to derive the general relativistic magnetohydrodynamic equations for cold plasma in spatially flat Schwarzschild metric. Respective perturbed equations are linearized for non-magnetized and magnetized plasmas…
A simple ordinary differential equation is derived governing the red-shifts of wave-fronts propagating through a non-stationary spherically symmetric space-time. Approach to an event horizon corresponds to approach to a fixed point; in…
In this note, we derive (to third order in derivatives of the fluid velocity) a 2+1 dimensional theory of fluid dynamics that governs the evolution of generic long-wavelength perturbations of a black brane or large black hole in…
We investigate the thermodynamics and stability of the horizons in warped anti-de Sitter black holes of the new massive gravity under the scattering of a massive scalar field. Under scattering, conserved quantities can be transferred from…
We investigate the impact of oscillations of a black-hole mass around its average value on the three-dimensional black hole geometry. Drawing on a classical framework that conceptualizes fluctuations near an event horizon as mass…
We use global three dimensional radiation magneto-hydrodynamical simulations to study accretion disks onto a $5\times 10^8M_{\odot}$ black hole with accretion rates varying from $\sim 250L_{Edd}/c^2$ to $1500 L_{Edd}/c^2$. We form the disks…
We derive and investigate the physical properties of asymptotically flat noncommutative regular charged black holes with a Gaussian mass density distribution and a Weibull electric charge density distribution. Both distributions replace the…
In the context of a two-dimensional exactly solvable model, the dynamics of quantum black holes is obtained by analytically continuing the description of the regime where no black hole is formed. The resulting spectrum of outgoing radiation…
We study a black hole in an expanding Universe during the radiation-dominated stage. In the case when the black hole radius is much smaller than the cosmological horizon, we present a solution of the Einstein equations for the metric, the…
In this work, we exactly derive the solution for the gravitational field of a black hole in Eddington-inspired Born-Infeld (EiBI) gravity, surrounded by perfect fluid dark matter. We analyze how the event horizon and the black hole…
In models of minicharged dark matter associated with a hidden $U(1)$ symmetry, astrophysical black holes may acquire a "dark" charge, in such a way that the inspiral dynamics of binary black holes can be formally described by an…
We investigate the thermodynamics of a four-dimensional charged black hole in a finite cavity in asymptotically flat and asymptotically de Sitter space. In each case, we find a Hawking-Page-like phase transition between a black hole and a…
We study black holes in three-dimensional Chern-Simons gravity with a negative cosmological constant. In particular, we identify how the Chern-Simons interactions between a scattering particle and a black hole project the particle…
The merger of binary black holes produces a series of decaying oscillations, during which energy is radiated in gravitational waves. The characteristic signal in the ringdown phase can be described by complex oscillation frequencies called…
We investigate the scalar field equation in a (2+1)-dimensional charged BTZ black hole. The quasinormal spectra of the solution are obtained applying two different methods and good convergence between both is achieved. Using the…
This is an extended version of the previous paper (hep-th/0701272). Quantum fields near horizons can be described in terms of an infinite set of two-dimensional conformal fields. We first generalize the method of Christensen and Fulling to…
In this work, we wish to address the question -- whether the quasi-normal modes, the characteristic frequencies associated with perturbed black hole spacetimes, central to the stability of these black holes, are themselves stable. Though…