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Related papers: Black Holes without Event Horizons

200 papers

Basic properties of black holes are explained in terms of trapping horizons. It is shown that matter and information will escape from an evaporating black hole. A general scenario is outlined whereby a black hole evaporates completely…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Sean A. Hayward

Event Horizon, a null hypersurface defining the boundary of the black hole region of a spacetime, is not particularly useful for evolving black holes since it is non-local in time. Instead, one uses the more tangible concept of Apparent…

General Relativity and Quantum Cosmology · Physics 2022-02-23 Emel Altas , Bayram Tekin

We present an introduction to dynamical trapping horizons as quasi-local models for black hole horizons, from the perspective of an Initial Value Problem approach to the construction of generic black hole spacetimes. We focus on the…

General Relativity and Quantum Cosmology · Physics 2015-05-30 José Luis Jaramillo

Black holes monopolize nowadays the center stage of fundamental physics. Yet, they are poorly understood objects. Notwithstanding, from their generic properties, one can infer important clues to what a fundamental theory, a theory that…

General Relativity and Quantum Cosmology · Physics 2008-04-05 José P. S. Lemos

When black holes are dynamical, event horizons are replaced by apparent and trapping horizons. Conformal and Kerr-Schild transformations are widely used in relation with dynamical black holes and we study the behaviour under such…

General Relativity and Quantum Cosmology · Physics 2015-06-18 Valerio Faraoni , Vincenzo Vitagliano

Although a black hole need not be spherical in higher dimensions, its event horizon cannot have arbitrary topology. Here we review some of the known constraints on horizon topology for higher dimensional black holes.

General Relativity and Quantum Cosmology · Physics 2011-11-24 Gregory J. Galloway

The supposed information paradox for black holes is based on the fundamental misunderstanding that black holes are usefully defined by event horizons. Understood in terms of locally defined trapping horizons, the paradox disappears:…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Sean A. Hayward

Quite recently, some new mathematical approaches to black holes have appeared in the literature. They do not rely on the classical concept of event horizon -- which is very global, but on the local concept of hypersurfaces foliated by…

Astrophysics · Physics 2009-06-23 Eric Gourgoulhon , Jose Luis Jaramillo

Classical black holes and event horizons are highly non-local objects, defined in relation to the causal past of future null infinity. Alternative, quasilocal characterizations of black holes are often used in mathematical, quantum, and…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Ivan Booth

Although we know that black holes are characterized by a temperature and an entropy, we do not yet have a satisfactory microscopic ``statistical mechanical'' explanation for black hole thermodynamics. I describe a new approach that…

General Relativity and Quantum Cosmology · Physics 2016-01-27 S. Carlip

To derive black hole thermodynamics in any quantum theory of gravity, one must introduce constraints that ensure that a black hole is actually present. For a large class of black holes, the imposition of such ``horizon constraints'' allows…

General Relativity and Quantum Cosmology · Physics 2015-05-13 S. Carlip

This paper considers the nature of apparent horizons for astrophysical black hole situated in a realistic cosmological context. Using semi-tetrad covariant methods we study the local evolutions of the boundaries of the trapped region in the…

General Relativity and Quantum Cosmology · Physics 2014-11-14 George F R Ellis , Rituparno Goswami , Aymen I. M. Hamid , Sunil D. Maharaj

This paper discusses the thermodynamics of a black hole with respect to Hawking radiation and the entropy. We look at a unified picture of black hole entropy and curvature and how this can lead to the usual black hole luminosity due to…

Cosmology and Nongalactic Astrophysics · Physics 2010-02-17 C Sivaram , Kenath Arun

In calculations of gravitational collapse to form black holes, trapping horizons (foliated by marginally trapped surfaces) make their first appearance either within the collapsing matter or where it joins on to a vacuum exterior. Those…

General Relativity and Quantum Cosmology · Physics 2017-06-19 Alexis Helou , Ilia Musco , John C. Miller

We have developed a powerful and efficient method for locating the event horizon of a black hole spacetime, making possible the study of the dynamics of event horizons in numerical relativity. We describe the method and apply it to a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Peter Anninos , David Bernstein , Steven Brandt , Joan Masso , Edward Seidel , Larry Smarr , Wai-Mo Suen , Paul Walker

We review the classical thermodynamics and the greybody factors of general (rotating) non-extreme black holes and discuss universal features of their near-horizon geometry. We motivate a microscopic interpretation of general black holes…

High Energy Physics - Theory · Physics 2009-09-25 Mirjam Cvetic , Finn Larsen

We present a statistical mechanical calculation of the thermodynamical properties of (non rotating) isolated horizons. The introduction of Planck scale allows for the definition of an universal horizon temperature (independent of the mass…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Amit Ghosh , Alejandro Perez

The usual discussions about black hole dynamics involve analogies with laws of thermodynamics especially in connection with black hole entropy and the associated holographic principle. We explore complementary aspects involving…

General Physics · Physics 2011-05-23 C. Sivaram

We work with the notion of apparent/trapping horizons for spherically symmetric, dynamical spacetimes: these are quasi-locally defined, simply based on the behaviour of congruence of light rays. We show that the sign of the dynamical…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Alexis Helou

This is an introductory, up-to-date review of the essentials of black hole thermodynamics. The main topics surveyed are: (i) the four laws of thermodynamics as applied to a black hole horizon, and the current status of their proofs; (ii)…

General Relativity and Quantum Cosmology · Physics 2018-07-12 Aron C. Wall