相关论文: Absorption by stringy black holes

In this paper we track the non-linear spherical evolution of a massless scalar field onto a Schwarzschild black hole space-time as a first approximation to the accretion of cosmologically motivated classical scalar fields. We perform an…

Following Sanchez's approach we investigate the effect of scalar mass in the absorption and emission problems of 4d Schwarzschild black hole. The absorption cross sections for arbitrary angular momentum of the scalar field are computed…

Accurate and powerful analytic and computational methods developped by the author allow to obtain the highly non trivial total absorption spectrum of the Black Hole, as well as phase shifts and cross sections (elastic and inelastic), the…

We investigate the propagation of massless particles and scalar fields in the background of Hayward regular black holes. We compute the absorption and scattering cross sections and compare our numerical results with some analytical…

The presence of charge promotes the propensity of a rotating black hole to support the propagation of electromagnetic plane waves with negative phase velocity (NPV) in its ergosphere, whether the Kerr-Newman or the Kerr-Sen metric…

We investigate the low-frequency absorption cross section of the electromagnetic waves for the extreme Reissner-Nordstrom black holes in higher dimensions. We first construct the exact solutions to the relevant wave equations in the…

We consider a macroscopic charge-current carrying (cosmic) string in the background of a Schwarzschild black hole. The string is taken to be circular and is allowed to oscillate and to propagate in the direction perpendicular to its plane…

By using semi-analytical method,we investigate the transmission and reflection coefficient and absorption and scattering cross section of spin 0,1,2 particles which are massless from a charged non rotating black holes. Here orbiting…

We study the reflection and transmission coefficients and the absorption cross section for scalar fields in the background of a Lifshitz black hole in three-dimensional conformal gravity with $z=0$, and we show that the absorption cross…

We present an exact solution of Einstein's equation that describes the gravitational shockwave of a massless particle on the horizon of a Kerr-Newman black hole. The backreacted metric is of the generalized Kerr-Schild form and is Type II…

The metrics of gravitational shock waves for a Schwarzschild black hole in ordinary coordinates and for a Kerr black hole in Boyer-Lindquist coordinates are derived. The Kerr metric is discussed for two cases: the case of a Kerr black hole…

We examine new tests for (non-)extremal Reissner-Nordstr\"om/Conformal field theory correspondences (RN/CFT) in this paper. The decay rate of the charged scalar wave sourced by an orbiting star around the black hole is computed and is…

In this work, we investigate the scattering and absorption of spin 0 particles for electrically charged black holes in two gravity models with spontaneous Lorentz symmetry breaking. The first one is the so-called bumblebee model that…

We study the electrically-charged massless scalar response to the general Kerr-Newman black hole and obtain the exact (complex) response coefficients, whose real parts are the Love numbers. We find there is a curious discontinuity between…

We study gravitational absorption effects using effective on-shell scattering amplitudes. We develop an in-in probability-based framework involving plane- and partial-wave coherent states for the incoming wave to describe the interaction of…

We consider an electric charge, minimally coupled to the Maxwell field, rotating around a Schwarzschild black hole. We investigate how much of the radiation emitted from the swirling charge is absorbed by the black hole and show that most…

This paper investigates the observable properties of a Kerr-Sen black hole surrounded by a thin accretion disk, focusing on the impact of the black hole's spin and charge on the image. Using ray-tracing techniques, we conduct a detailed…

We show that a quantum scalar particle in the gravitational field of a massive body of radius R which slightly exceeds the Schwarzschild radius r_s, possesses a dense spectrum of narrow resonances. Their lifetimes and density tend to…

We consider the problem of star consumption by supermassive black holes in non-spherical (axisymmetric, triaxial) galactic nuclei. We review the previous studies of the loss-cone problem and present a novel simulation method which allows to…

We examine the spectrum of a massive scalar particle interacting with the strong gravitational field of a static, spherically symmetric object which is not quite massive enough to be a black hole. As was found in the case of massless…