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Related papers: Noncommutativity and the Weak Cosmic Censorship

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We test the cosmic censorship conjecture for a class of polarized AdS black branes (holes) in the Einstein-Maxwell theory at large number of dimensions $D$. We first derive a new set of effective equations describing the dynamics of the…

High Energy Physics - Theory · Physics 2020-05-20 Norihiro Iizuka , Akihiro Ishibashi , Kengo Maeda

Recently Hertog, Horowitz, and Maeda have argued that cosmic censorship can be generically violated in string theory in anti-de Sitter spacetime by considering a collapsing bubble of a scalar field whose mass saturates the…

High Energy Physics - Theory · Physics 2009-11-10 Michael Gutperle , Per Kraus

We investigate two simplified non-singular cyclic models with a negative time-varying cosmological constant to represent the non-conventional mechanism of negative cosmological constant expected to address the late-time cosmic acceleration.…

General Relativity and Quantum Cosmology · Physics 2026-05-21 Nasr Ahmed , Kazuharu Bamba

We study the evolution of bubble spacetimes in vacuum and electrovac scenarios by numerical means. We find strong evidence against the formation of naked singularities in (i) scenarios with negative masses displaying initially collapsing…

High Energy Physics - Theory · Physics 2009-11-10 Olivier Sarbach , Luis Lehner

Low energy effective action of bosonic string theory possesses a kind of singular static solution which can be interpreted as a naked singularity. Based on the Hohm-Zwiebach action, the naked singularities could be smoothed out by…

High Energy Physics - Theory · Physics 2022-06-14 Shuxuan Ying

The hypothesis of cosmic censorship plays a crucial role in classical general relativity, namely, to ensure that naked singularities would never occur from the black hole singularity. In this paper, we will present how energy conditions…

General Relativity and Quantum Cosmology · Physics 2021-12-24 Javad T. Firouzjaee

In this paper we study the dynamics of the trapped region using a frame independent semi-tetrad covariant formalism for general Locally Rotationally Symmetric (LRS) class II spacetimes. We covariantly prove some important geometrical…

General Relativity and Quantum Cosmology · Physics 2014-07-31 Aymen I. M. Hamid , Rituparno Goswami , Sunil D. Maharaj

A thought experiment considered recently in the literature, in which it is investigated whether a dyonic Kerr-Newman black hole can be destroyed by overcharging or overspinning it past extremality by a massive complex scalar test field, is…

General Relativity and Quantum Cosmology · Physics 2012-07-13 Gabor Zsolt Toth

Cosmological measurements are affected by the energy density of both active and sterile massive neutrinos. We extend here a recent analysis of current cosmological data to non minimal cosmologies. Several possible scenarios are examined: a…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Elena Giusarma , Maria Archidiacono , Roland de Putter , Alessandro Melchiorri , Olga Mena

We perform extensive nonlinear numerical simulations of the spherical collapse of (charged) wavepackets onto a charged black hole within Einstein-Maxwell theory and in Einstein-Maxwell-scalar theory featuring nonminimal couplings and a…

General Relativity and Quantum Cosmology · Physics 2021-11-03 Fabrizio Corelli , Taishi Ikeda , Paolo Pani

We investigate the stability of the inner horizon of a rotating BTZ black hole. We show that linear perturbations arising from smooth initial data are arbitrarily differentiable at the inner horizon if the black hole is sufficiently close…

High Energy Physics - Theory · Physics 2020-01-29 Oscar J. C. Dias , Harvey S. Reall , Jorge E. Santos

We find asymptotically anti de Sitter solutions in N=8 supergravity which have negative total energy. This is possible since the boundary conditions required for the positive energy theorem are stronger than those required for finite mass…

High Energy Physics - Theory · Physics 2009-11-10 Thomas Hertog , Gary T. Horowitz , Kengo Maeda

We show that the cosmological constant appears as a Lagrange multiplier if nature is described by a canonical noncommutative spacetime. It is thus an arbitrary parameter unrelated to the action and thus to vacuum fluctuations. The…

High Energy Physics - Theory · Physics 2008-11-26 Xavier Calmet

A very interesting work that has recently appeared in the physics literature [arXiv:1810.00886] claims that the strong cosmic censorship conjecture, a fundamental cornerstone of black-hole physics, may be violated in asymptotically de…

General Relativity and Quantum Cosmology · Physics 2018-10-12 Shahar Hod

Tests of the weak cosmic censorship conjecture examine the possibility of the breakdown of predictivity of the gravitational theory considered, by checking if curvature singularities typically present in black hole spacetimes are concealed…

High Energy Physics - Theory · Physics 2024-05-09 Antonia M. Frassino , Jorge V. Rocha , Andrea P. Sanna

We explicitly confirm that spatially flat non-singular bouncing cosmologies make sense as effective theories. The presence of a non-singular bounce in a spatially flat universe implies a temporary violation of the null energy condition,…

High Energy Physics - Theory · Physics 2016-05-11 Michael Koehn , Jean-Luc Lehners , Burt Ovrut

The strong cosmic censorship conjecture, whose validation asserts the deterministic nature of general relativity, has been studied for charged BTZ black holes in three dimensional general relativity, as well as for Nth order pure Lovelock…

General Relativity and Quantum Cosmology · Physics 2022-06-08 Chiranjeeb Singha , Sumanta Chakraborty , Naresh Dadhich

We study CMB constraints on a model with a cosmological constant and a fraction of dark matter non-minimally coupled to a massless scalar field. In this scenario, there is an extra gravity-like fifth force which can affect the evolution of…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-09 Sophie C. F. Morris , Anne M. Green

Cosmology and astrophysics provide various ways to study the properties of dark matter even if they have negligible non-gravitational interactions with the Standard Model particles and remain hidden. We study a type of hidden dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-03 Weikang Lin , Xingang Chen , Himanish Ganjoo , Liqiang Hou , Katherine J. Mack

A consistent combination of quantum geometry effects rules out a large class of models of loop quantum cosmology and their critical densities as they have been used in the recent literature. In particular, the critical density at which an…

General Relativity and Quantum Cosmology · Physics 2009-03-27 Martin Bojowald