English
Related papers

Related papers: Black holes

200 papers

We study a simple system of two hyperbolic semi-linear equations, inspired by the Einstein equations. The system, which was introduced in gr-qc/0612136, is a model for singularity formation inside black holes. We show for a particular case…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Dan Gorbonos , Gershon Wolansky

Continuous sequences of asymptotically flat solutions to the Einstein-Maxwell equations describing regular equilibrium configurations of ordinary matter can reach a black hole limit. For a distant observer, the spacetime becomes more and…

General Relativity and Quantum Cosmology · Physics 2015-02-12 Reinhard Meinel , Martin Breithaupt , Yu-Chun Liu

We present a class of exact analytic and static, spherically symmetric black hole solutions in the semi-classical Einstein equations with Weyl anomaly. The solutions have two branches, one is asymptotically flat and the other asymptotically…

High Energy Physics - Theory · Physics 2010-04-30 Rong-Gen Cai , Li-Ming Cao , Nobuyoshi Ohta

As an example of a black hole in a non-flat background a composite static spacetime is constructed. It comprises a vacuum Schwarzschild spacetime for the interior of the black hole across whose horizon it is matched on to the spacetime of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 K. Rajesh Nayak , M. A. H. MacCallum , C. V. Vishveshwara

In the context of f(R) modified gravity theories, we study the Kerr-Newman black-hole solutions. We study non-zero constant scalar curvature solutions and discuss the metric tensor that satisfies the modified field equations. We determine…

General Relativity and Quantum Cosmology · Physics 2011-10-04 J. A. R. Cembranos , A. de la Cruz-Dombriz , P. Jimeno Romero

If one assumes the validity of conventional quantum field theory in the vicinity of the horizon of a black hole, one does not find a quantum mechanical description of the entire black hole that even remotely resembles that of conventional…

General Relativity and Quantum Cosmology · Physics 2008-11-26 G. 't Hooft

Black holes in equilibrium can be defined locally in terms of the so-called isolated horizon boundary condition given on a null surface representing the event horizon. We show that this boundary condition can be treated in a manifestly…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Jonathan Engle , Karim Noui , Alejandro Perez

Black hole configurations offer insights on the non-linear aspects of gravitational theories, and can suggest testable predictions for modifications of General Relativity. In this work, we examine exact black hole configurations in…

High Energy Physics - Theory · Physics 2016-08-17 Javier Chagoya , Gustavo Niz , Gianmassimo Tasinato

Proof that black holes exist will likely require confirmation of the existence of event horizons. The common assumption that the mere existence of large compact masses proves the case for black holes is an unwarranted extrapolation of…

Astrophysics · Physics 2007-05-23 Stanley L. Robertson

We give a comparative description of different types of regular static, spherically symmetric black holes (BHs) and discuss in more detail their particular type, which we suggest to call black universes. The latter have a Schwarzschild-like…

General Relativity and Quantum Cosmology · Physics 2008-11-26 K. A. Bronnikov , H. Dehnen , V. N. Melnikov

The purpose of this chapter is to provide an overview of the exciting field of black hole quasi-normal modes and its capabilities to test general relativity in the 21st century. After motivating this line of research, we provide a…

General Relativity and Quantum Cosmology · Physics 2023-05-04 Nicola Franchini , Sebastian H. Völkel

Black holes are perhaps the most strange and fascinating objects known to exist in the universe. Our understanding of space and time is pushed to its limits by the extreme conditions found in these objects. They can be used as natural…

Astrophysics · Physics 2008-05-15 Gustavo E. Romero

We show that a formalism for analyzing the near-horizon conformal symmetry of Schwarzschild black holes using a scalar field probe is capable of describing black hole decay. The equation governing black hole decay can be identified as the…

High Energy Physics - Theory · Physics 2015-06-26 Kumar S. Gupta , Siddhartha Sen

Black hole physics currently lacks a fully coherent understanding of the black hole mass (density), entropy, and interior (non-)singularity. These concepts are related to the black hole radius, area (of the horizon), and volume (within the…

General Relativity and Quantum Cosmology · Physics 2026-05-20 Arno Keppens , Lester Kurvers

We describe the possible forms of black hole images, viewed by a distant observer. These images are numerically calculated basing on general relativity and equations of motion in the Kerr-Newman metric. Black hole image is a gravitationally…

General Relativity and Quantum Cosmology · Physics 2024-08-27 Vyacheslav Ivanovich Dokuchaev

The interior of the black hole can be described by anisotropic cosmology. By quantizing the metric function, we can obtain the Wheeler-DeWitt equation for inside the horizon. In order to interpret the wave function consistently, one needs…

General Relativity and Quantum Cosmology · Physics 2022-09-08 Dong-han Yeom

The objective of this work is to present a non-technical introduction to black hole physics. The main properties of the four types of black hole allowed by the no-hair theorem are discussed, and some properties of spacetime around a black…

Popular Physics · Physics 2024-06-19 Jorge Pinochet

The black hole paradigm, while remarkably successful, raises fundamental questions-both classical and quantum-about the nature of spacetime, horizons, and singularities. Black hole mimickers, horizonless ultra-compact objects, have emerged…

In backgrounds with compact dimensions there may exist several phases of black objects including the black-hole and the black-string. The phase transition between them raises puzzles and touches fundamental issues such as topology change,…

High Energy Physics - Theory · Physics 2009-11-10 Barak Kol , Evgeny Sorkin , Tsvi Piran

We investigate the properties of charged black hole geometries in nonlinear electrodynamics. We focus on the recently reported analytic charged black hole solutions to illustrate the consequences of a non-monotonic lapse function that…

High Energy Physics - Theory · Physics 2026-05-18 Lewis Croney , Ruth Gregory , Ansh Gupta , Carlos J. Ramírez-Valdez