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Related papers: Naked Singularity Formation In f(R) Gravity

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We investigate here the locally naked singularity formed due to a spherically symmetric inhomogeneous collapsing cloud having non-zero isotropic pressure, in terms of its strength. Sufficient condition provided by Clarke and Krolak for it…

General Relativity and Quantum Cosmology · Physics 2020-03-04 Karim Mosani , Dipanjan Dey , Pankaj S. Joshi

A naked singularity occurs in the generic collapse of an inhomogeneous dust ball. We study the even-parity mode of gravitational waves from a naked singularity of the Lema\^{\i}tre-Tolman-Bondi spacetime. The wave equations for…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Hideo Iguchi , Tomohiro Harada , Ken-ichi Nakao

The curvature singularity in viable f(R) gravity models is examined when the background density is dense. This singularity could be eliminated by adding the $R^{2}$ term in the Lagrangian. Some of cosmological consequences, in particular…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-03 Chung-Chi Lee , Chao-Qiang Geng , Louis Yang

We study the self-compactification of extra dimensions via higher curvature gravity, f(R), where f(R) is the generic function of the Ricci scalar R. First, we reduce pure f(R) theory to a scalar-tensor theory by a conformal transformation.…

High Energy Physics - Theory · Physics 2011-02-16 Beyhan Pulice , Sukru Hanif Tanyildizi

We study the spherically symmetric gravitational collapse of massless scalar matter field in asymptotic flat spacetime in $f(R)$ gravity. In the Einstein frame of $f(R)$ gravity, an additional scalar field arises due to the conformal…

General Relativity and Quantum Cosmology · Physics 2016-11-15 Cheng-Yong Zhang , Zi-Yu Tang , Bin Wang

Penrose's weak cosmic censorship conjecture asserts that spacetime singularities produced by gravitational collapse are generically hidden behind event horizons, thus preventing them from causally influencing distant observers and…

General Relativity and Quantum Cosmology · Physics 2026-03-16 Giovanni Caridi , Fabrizio Corelli , Paolo Pani

We study the problem of the gravitational collapse of an object as seen by an external observer. We assume that the resultant spacetime is a match of an external Vaidya spacetime with an interior Friedmann-Lema\^itre-Robertson-Walker (FRLW)…

General Relativity and Quantum Cosmology · Physics 2023-12-27 Eduardo Bittencourt , Alan G. Cesar , Jonas P. Pereira

Choptuik has demonstrated that naked singularities can arise in gravitational collapse from smooth, asymptotically flat initial data, and that such data have codimension one in spherical symmetry. Here we show, for perfect fluid matter with…

General Relativity and Quantum Cosmology · Physics 2009-12-30 Carsten Gundlach

It has previously been shown [W. Rudnicki, Phys. Lett. A 224, 45 (1996)] that a generic gravitational collapse cannot result in a naked singularity accompanied by closed timelike curves. An important role in this result plays the so-called…

General Relativity and Quantum Cosmology · Physics 2009-10-31 W. Rudnicki , P. Zieba

This paper is devoted to study the gravitational charged perfect fluid collapse in the Friedmann universe models with cosmological constant. For this purpose, we assume that the electromagnetic field is so weak that it does not introduce…

General Relativity and Quantum Cosmology · Physics 2015-05-18 M. Sharif , G. Abbas

Though the cosmic censorship conjecture states that spacetime singularities must be hidden from an asymptotic observer by an event horizon, naked singularities can form as the end product of a gravitational collapse under suitable initial…

General Relativity and Quantum Cosmology · Physics 2020-12-24 Avijit Chowdhury , Narayan Banerjee

The formation of a naked singularity in $f(R)$ global monopole spacetime is considered in view of quantum mechanics. Quantum test fields obeying the Klein$-$Gordon, Dirac and Maxwell equations are used to probe the classical timelike naked…

High Energy Physics - Theory · Physics 2014-02-04 O. Gurtug , M. Halilsoy , S. Habib Mazharimousavi

Generalizing the results of Joshi and Dwivedi in Commun.Math.Phys. 146, p.333 (1992), it is pointed out that strong curvature naked singularities could occur in the self-similar gravitational collapse of any form of matter satisfying the…

General Relativity and Quantum Cosmology · Physics 2009-10-22 P. S. Joshi , I. H. Dwivedi

In this paper, we study the gravitational collapse of null dust in the cylindrically symmetric spacetime. The naked singularity necessarily forms at the symmetry axis. We consider the situation in which null dust is emitted again from the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Yasunari Kurita , Ken-ichi Nakao

The motion of a spherical dust cloud is described by the Lemaitre-Tolman-Bondi solution and is completely specified by initial values of distributions of the rest mass density and specific energy of the dust fluid. From generic initial…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Hideo Iguchi , Ken-ichi Nakao , Tomohiro Harada

Gravitational collapse singularities are undesirable, yet inevitable to a large extent in General Relativity. When matter satisfying null energy condition collapses to the extent a closed trapped surface is formed, a singularity is…

General Relativity and Quantum Cosmology · Physics 2020-03-09 Karthik H. Shankar

We analyze here the final fate of complete gravitational collapse of a massless scalar field within general relativity. A class of dynamical solutions with initial data close to the Friedmann-Lemaitre-Robertson-Walker (FLRW) collapse model…

General Relativity and Quantum Cosmology · Physics 2012-02-29 Rituparno Goswami , Pankaj S. Joshi , Daniele Malafarina

In this note we explore a non-static spacetime in quantum regime in the background of $f(R)$ gravity. The time dependent Vaidya metric which represents the spacetime of a radiating body like star is studied in an energy dependent gravity's…

General Relativity and Quantum Cosmology · Physics 2020-04-22 Prabir Rudra

It has been suggested that a naked singularity may be a good candidate for a strong gravitational wave burster. The naked singularity occurs in the generic collapse of an inhomogeneous dust ball. We study odd-parity mode of gravitational…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Hideo Iguchi , Tomohiro Harada , Ken-ichi Nakao

We model a compact radiant star that undergoes gravitational collapse from a certain initial static configuration until it becomes a black hole. The star consists of a fluid with anisotropy in pressures, bulk viscosity, in addition to the…

General Relativity and Quantum Cosmology · Physics 2023-04-26 A. C. Mesquita , M. F. A. da Silva
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