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Related papers: Black Holes in a Compactified Spacetime

200 papers

It has been argued by several authors that the quantum mechanical spectrum of black hole horizon area must be discrete. This has been confirmed in different formalisms, using different approaches. Here we concentrate on two approaches, the…

High Energy Physics - Theory · Physics 2009-11-07 Saurya Das , P. Ramadevi , U. A. Yajnik

Time-dependent spherically-symmetric perturbations of Schwarzschild black holes are studied within torsion bigravity, i.e., within generalized Einstein-Cartan theories where the dynamical torsion carries massive spin-2 excitation. We reduce…

General Relativity and Quantum Cosmology · Physics 2021-07-21 Vasilisa Nikiforova

We have studied polarized image of a Schwarzschild black hole with an equatorial thin accretion disk as photon couples to Weyl tensor. The birefringence of photon originating from the coupling affect the black hole shadow, the thin disk…

General Relativity and Quantum Cosmology · Physics 2021-11-15 Zelin Zhang , Songbai Chen , Xin Qin , Jiliang Jing

We consider a vacuum static spacetime in a finite size cavity. On the boundary, we specify a metric and a finite constant local temperature $T$. No spherical or any other spatial symmetry is assumed. We show that (i) inside a cavity, only a…

General Relativity and Quantum Cosmology · Physics 2019-03-27 O. B. Zaslavskii

By performing a Taylor expansion along the extra dimension of a metric describing a black hole on a brane, we explore the influence of the embedding space on the black hole horizon. In particular, it is shown that the existence of a Kottler…

General Relativity and Quantum Cosmology · Physics 2012-12-19 J. M. Hoff da Silva , Roldao da Rocha

A variety of historical coordinates in which the Schwarzschild metric is regular over the whole of the extended spacetime are compared and the hypersurfaces of constant coordinate are graphically presented. While the Kruscal form (one of…

General Relativity and Quantum Cosmology · Physics 2014-01-16 W G Unruh

We consider a microscopic model of a stretched horizon of the Schwarzschild black hole. In our model the stretched horizon consists of a finite number of discrete constituents. Assuming that the quantum states of the Schwarzschild black…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Jarmo Mäkelä

An analytical metric of four-dimensional General Relativity, representing an array of collinear and accelerating black holes, is constructed with the inverse scattering method. The solution can be completely regularised from any conical…

General Relativity and Quantum Cosmology · Physics 2023-08-22 Marco Astorino , Adriano Viganò

We present an evidence, that the volumes of compactified spaces as well as the areas of black hole horizons must be quantized in Planck units. This quantization has phenomenological consequences, most dramatic being for micro black holes in…

High Energy Physics - Theory · Physics 2011-02-09 Gia Dvali , Cesar Gomez , Slava Mukhanov

We investigate the astrophysical consequences of black holes in quadratic gravity, characterized by the parameters $S_0$, $S_2$, $m_0$ and $m_2$, in addition to the black hole mass $M$. To evaluate the physical validity of the fundamental…

General Relativity and Quantum Cosmology · Physics 2024-12-24 Somi Aktar , Niyaz Uddin Molla , Farook Rahaman , G. Mustafa

One crucial problem in relativistic astrophysics is that of the nature of black hole candidates. It is usually assumed that astrophysical black holes are described by the Schwarzschild or Kerr space-times; however, there is no direct…

General Relativity and Quantum Cosmology · Physics 2020-11-05 J. A. Arrieta-Villamizar , J. M. Velásquez-Cadavid , O. M. Pimentel , F. D. Lora-Clavijo , A. C. Gutiérrez-Piñeres

In four-dimensional vacuum general relativity the only known static, exact and analytical black hole solution is given by the Schwarzschild spacetime. In this paper this renowned metric is generalised by adding another integrating constant,…

General Relativity and Quantum Cosmology · Physics 2026-01-26 Marco Astorino

We study scattering of waves by black holes. Solving a massless scalar field with a point source in the Schwarzschild spacetime, waves scattered by the black hole is obtained numerically. We then reconstruct images of the black hole from…

General Relativity and Quantum Cosmology · Physics 2015-06-15 Ken-ichiro Kanai , Yasusada Nambu

We study interior of a charged, non-rotating distorted black hole. We consider static and axisymmetric black holes, and focus on a special case when an electrically charged distorted solution is obtained by the Harrison-Ernst transformation…

General Relativity and Quantum Cosmology · Physics 2010-04-14 Shohreh Abdolrahimi , Valeri P. Frolov , Andrey A. Shoom

Based on the scalar-tensor-vector modified gravitational theory, a modified gravity Schwarzschild black hole solution has been given in the existing literature. Such a black hole spacetime is obtained through the inclusion of a modified…

General Relativity and Quantum Cosmology · Physics 2022-06-10 Daqi Yang , Wenfu Cao , Naying Zhou , Hongxing Zhang , Wenfang Liu , Xin Wu

Some judiciously chosen local curvature scalars can be used to invariantly characterize event horizons of black holes in $D > 3$ dimensions, but they fail for the three dimensional Ba\~nados-Teitelboim-Zanelli (BTZ) black hole since all…

High Energy Physics - Theory · Physics 2020-04-22 Aydin Tavlayan , Bayram Tekin

We use the Ernst-Schwarzschild solution for a black hole immersed in a uniform magnetic field to estimate corrections to the bending angle and time delay due-to presence of weak magnetic fields in galaxies and between galaxies, and also…

General Relativity and Quantum Cosmology · Physics 2008-11-26 R. A. Konoplya

We construct and investigate a compactified version of the four-dimensional Reissner-Nordstrom-NUT solution, generalizing the compactified Schwarzschild black hole that has been previously studied by several workers. Our approach to…

General Relativity and Quantum Cosmology · Physics 2013-05-29 Max Karlovini , Rikard von Unge

The entropy of a seven dimensional Schwarzschild black hole of arbitrary large radius is obtained by a mapping onto a near extremal self-dual three-brane whose partition function can be evaluated. The three-brane arises from duality after…

High Energy Physics - Theory · Physics 2009-10-31 F. Englert , E. Rabinovici

Spacetime metrics describing `non-singular' black holes are commonly studied in the literature as effective modification to the Schwarzschild solution that mimic quantum gravity effects removing the central singularity. Here we point out…

General Relativity and Quantum Cosmology · Physics 2015-03-25 Tommaso De Lorenzo , Costantino Pacilio , Carlo Rovelli , Simone Speziale