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Related papers: Naked Singularity Formation In Brans-Dicke Theory

200 papers

We consider quantum theoretical effects of the sudden change of the boundary conditions which mimics the occurrence of naked singularities. For a simple demonstration, we study a massless scalar field in $(1 + 1)$-dimensional Minkowski…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Akihiro Ishibashi , Akio Hosoya

Gravitational collapse of radiation shells in a non self-similar higher dimensional spherically symmetric spacetime is studied. Strong curvature naked singularities form for a highly inhomogeneous collapse, violating the cosmic censorship…

General Relativity and Quantum Cosmology · Physics 2009-11-07 S G Ghosh , R V Saraykar , A Beesham

The collapse of thin dust shells in 2+1 dimensional gravity with and without a cosmological constant in analyzed. A critical value of the shell's mass as a function of its radius and position is derived. For $\Lambda < 0$, a naked…

General Relativity and Quantum Cosmology · Physics 2009-12-30 Yoav Peleg , Alan Steif

End state of gravitational collapse and the related cosmic censorship conjecture continue to be amongst the most important open problems in gravitation physics today. My purpose here is to bring out several aspects related to gravitational…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Pankaj S. Joshi

We consider here the classic scenario given by Oppenheimer, Snyder, and Datt, for the gravitational collapse of a massive matter cloud, and examine its stability under the introduction of small tangential stresses. We show, by offering an…

General Relativity and Quantum Cosmology · Physics 2011-02-02 Pankaj S. Joshi , Daniele Malafarina

In a Brans-Dicke (BD) cosmological model, the energy density associated with some scalar field decreases as $\displaystyle a^{{-2}(\frac{\omega_{o}+ {\frac12}%}{\omega_{o}+1})} $ with the scale factor $a(t)$ of the Universe, giving a matter…

Astrophysics · Physics 2009-10-31 S. del Campo , N. Cruz

Two dimensional (2D) analogue of vacuum sector of the Brans Dicke (BD) gravity [1] is studied to obtain dynamics of anisotropic spherically symmetric perfect fluid. Our obtained static solutions behave as dark matter with state equation…

General Relativity and Quantum Cosmology · Physics 2017-06-29 Hossein Ghaffarnejad

In this paper, we considered the gravitational collapse of a symmetric radiating star consisting of perfect fluid (baryonic) in the background of dark energy (DE) with general equation of state. The effect of DE on the singularity formation…

General Relativity and Quantum Cosmology · Physics 2021-11-17 Grishma Verma , Rajesh Kumar , Keshav Ram Mishra

We investigate the occurrence and nature of naked singularities in the gravitational collapse of a self-similar adiabatic perfect fluid in a five dimensional space-time. The naked singularities are found to be gravitationally strong in the…

General Relativity and Quantum Cosmology · Physics 2015-06-23 S G Ghosh , S B Sarwe , R V Saraykar

We study the gravitational collapse of a homogeneous time-dependent scalar field that, besides its coupling to curvature, it is also kinematically coupled to the Einstein tensor. This coupling is a part of the Horndeski theory and we…

General Relativity and Quantum Cosmology · Physics 2017-04-19 George Koutsoumbas , Konstantinos Ntrekis , Eleftherios Papantonopoulos , Minas Tsoukalas

We study the structure and stability of the recently discussed spherically symmetric Brans-Dicke black-hole type solutions with an infinite horizon area and zero Hawking temperature, existing for negative values of the coupling constant…

General Relativity and Quantum Cosmology · Physics 2009-10-31 K. A. Bronnikov , G. Clément , C. P. Constantinidis , J. C. Fabris

A theorem, giving necessary and sufficient condition for naked singularity formation in spherically symmetric non static spacetimes under hypotheses of physical acceptability, is formulated and proved. The theorem relates existence of…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Roberto Giambo' , Fabio Giannoni , Giulio Magli , Paolo Piccione

Motivated by the recent argument that in the TeV-scale gravity trans-Planckian domains of spacetime as effective naked singularities would be generated by high-energy particle (and black-hole) collisions, we investigate the quantum particle…

General Relativity and Quantum Cosmology · Physics 2012-03-06 Umpei Miyamoto , Hiroya Nemoto , Masahiro Shimano

Gravitational collapse of radiation in an anti-de Sitter background is studied. For the spherical case, the collapse proceeds in much the same way as in the Minkowski background, i.e., massless naked singularities may form for a highly…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Jose' P. S. Lemos

We present a quantum mechanical study of the bound states of a neutral scalar particle on the curved background described by the Reissner-Nordstr\"om (RN) spacetime that corresponds to a naked singularity. We show that there occurs both the…

General Relativity and Quantum Cosmology · Physics 2015-06-15 Valentin D. Gladush , Dmitry A. Kulikov

Under spherical symmetry, we show that the weak cosmic censorship holds for the gravitational collapse of the Einstein-Maxwell-charged scalar field system. Namely, for this system, with generic initial data, the formed spacetime…

General Relativity and Quantum Cosmology · Physics 2024-02-27 Xinliang An , Hong Kiat Tan

Cosmic censorship is known to fail in some well-controlled phenomena, calling into question the predictive power of General Relativity and opening up the possibility of observing Planck-scale physics. We propose that the cosmic censorship…

High Energy Physics - Theory · Physics 2022-03-07 Roberto Emparan

We study spherically symmetric gravitational collapse of a homogeneous perfect fluid in Rastall gravity. Considering a linear equation of state (EoS) for the fluid profiles, we examine the conditions under which the collapse scenario could…

General Relativity and Quantum Cosmology · Physics 2019-05-08 A. H. Ziaie , H. Moradpour , S. Ghaffari

It was investigated recently, with the aim of testing the weak cosmic censorship conjecture, whether an extremal Kerr black hole can be converted into a naked singularity by interaction with a massless classical Dirac test field, and it was…

General Relativity and Quantum Cosmology · Physics 2016-05-06 Gabor Zsolt Toth

Cosmological solutions of the Brans-Dicke theory are investigated by including a quantum effect coming from 1-loop correction of matter fields that couple to the scalar field. As the most serious result we face a cosmological ``constant''…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Yasunori Fujii