English
Related papers

Related papers: Not Yet for Us: the Nascent Black Hole

200 papers

Initial data for the spherically symmetric Einstein-Vlasov system is constructed whose past evolution is regular and whose future evolution contains a black hole. This is the first example of initial data with these properties for the…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Håkan Andréasson

Observation of an exploding black hole would provide the first direct evidence of primordial black holes, the first direct evidence of Hawking radiation, and definitive information on the particles present in nature. However, indirect…

High Energy Physics - Phenomenology · Physics 2025-10-08 Michael J. Baker , Joaquim Iguaz Juan , Aidan Symons , Andrea Thamm

We revisit our investigation of the claim of [1] that old black holes contain a firewall, i.e. an in-falling observer encounters highly excited states at a time much shorter than the light crossing time of the Schwarzschild radius. We used…

High Energy Physics - Theory · Physics 2014-02-03 Tom Banks , Willy Fischler , Sandipan Kundu , Juan F. Pedraza

A class of nonstationary spacetimes is obtained by means of a conformal transformation of the Schwarzschild metric, where the conformal factor $a(t)$ is an arbitrary function of the time coordinate only. We investigate several situations…

General Relativity and Quantum Cosmology · Physics 2017-05-05 Marina M. C. Mello , Alan Maciel , Vilson T. Zanchin

A reformulation of the calculation of the semi-classical energy-momentum tensor on a Schwarzschild background, the Bousso covariant entropy bound, and the ER=EPR conjecture of Maldacena and Susskind taken together suggest a scenario for the…

General Relativity and Quantum Cosmology · Physics 2014-06-17 James M. Bardeen

Moving mirrors have been used for a long time as simple models for studying various properties of black hole radiation, such as the thermal spectrum and entanglement entropy. These models are typically constructed to mimic the collapse of a…

General Relativity and Quantum Cosmology · Physics 2024-07-09 Evgenii Ievlev

We study the gravitational microlensing of various static and spherically symmetric non-singular black holes (and horizonless, non-singular compact objects of similar size). For pointlike sources we extend the parametrized post-Newtonian…

General Relativity and Quantum Cosmology · Physics 2026-02-05 Jens Boos , Hao Hu

An approach is presented to resolve key paradoxes in black hole physics through the application of complex Riemannian spacetime. We extend the Schwarzschild metric into the complex domain, employing contour integration techniques to remove…

General Relativity and Quantum Cosmology · Physics 2025-07-14 J. W. Moffat

Recently the Event Horizon Telescope observed black holes at event horizon scales for the first time, enabling us to now test the existence of event horizons. Although event horizons have by definition no observable features, one can look…

General Relativity and Quantum Cosmology · Physics 2024-09-18 Joost de Kleuver , Thomas Bronzwaer , Heino Falcke , Ramesh Narayan , Yosuke Mizuno , Oliver Porth , Hector Olivares

We investigate the consequences for the black hole area of introducing fractal structure for the horizon geometry. We create a three-dimensional spherical analogue of a 'Koch Snowflake' using a infinite diminishing hierarchy of touching…

General Relativity and Quantum Cosmology · Physics 2020-08-06 John D. Barrow

The definition of matter states on spacelike hypersurfaces of a 1+1 dimensional black hole spacetime is considered. Because of small quantum fluctuations in the mass of the black hole, the usual approximation of treating the gravitational…

High Energy Physics - Theory · Physics 2007-05-23 Miguel E. Ortiz

The presence of a bright "photon ring" surrounding a dark "black hole shadow" has been discussed as an important feature of the observational appearance of emission originating near a black hole. We clarify the meaning and relevance of…

High Energy Astrophysical Phenomena · Physics 2019-07-17 Samuel E. Gralla , Daniel E. Holz , Robert M. Wald

Creation of thermal distribution of particles by a black hole is independent of the detail of gravitational collapse, making the construction of the eternal horizons suffice to address the problem in asymptotically flat spacetimes. For…

General Relativity and Quantum Cosmology · Physics 2019-01-02 Sourav Bhattacharya

The accretion disk around a black hole and its emissions play an essential role in theoretical analysis of the black hole image. In the literature, two analytical toy models of accretions are widely adopted: the spherical model and the thin…

General Relativity and Quantum Cosmology · Physics 2025-03-13 Zhi-Shuo Qu , Towe Wang , Chao-Jun Feng

Two interesting hypotheses about black holes have been proposed. The older one states that microscopic black holes can be accountable for the observed dark matter density. The newer one states that black holes are coupled to the expansion…

General Relativity and Quantum Cosmology · Physics 2024-05-24 Samuel Kováčik

The case for the utility of Kruskal-Szekeres coordinates in classroom made by Augousti et al. in this journal (Eur. J. Phys. 33:1--11, 2012) is strengthened by extending their discussion beyond the event horizon of the black hole.…

General Relativity and Quantum Cosmology · Physics 2017-03-13 Klaus Kassner

How the supermassive black hole SgrA* in the Milky Way Center looks like for a distant observer? It depends on the black hole highlighting by the surrounding hot matter. The black hole shadow (the photon capture cross-section) would be…

High Energy Astrophysical Phenomena · Physics 2019-05-14 Vyacheslav Dokuchaev

This review discusses the current status of supermassive black hole research, as seen from a purely observational standpoint. Since the early '90s, rapid technological advances, most notably the launch of the Hubble Space Telescope, the…

Astrophysics · Physics 2010-04-29 Laura Ferrarese , Holland Ford

We investigate the black hole thermodynamics in a "deformed" relativity framework where the energy-momentum dispersion law is Lorentz-violating and the Schwarzchild-like metric is momentum-dependent with a Planckian cut-off. We obtain net…

General Relativity and Quantum Cosmology · Physics 2009-05-22 G. Salesi , E. Di Grezia

This paper revisits the conundrum faced when one attempts to understand the dynamics of black hole formation and evaporation without abandoning unitary evolution. Previous efforts to resolve this puzzle assume that information escapes in…

High Energy Physics - Theory · Physics 2009-10-22 S. B. Giddings