English
Related papers

Related papers: Generic Naked Singularities in Vaidya Spacetimes

200 papers

It was recently shown that the metric functions which describe a spherically symmetric space-time with vanishing radial pressure can be explicitly integrated. We investigate the nakedness and curvature strength of the shell-focusing…

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

A remarkable property of naked singularities in general relativity is their repulsive nature. The effects generated by repulsive gravity are usually investigated by analyzing the trajectories of test particles which move in the effective…

General Relativity and Quantum Cosmology · Physics 2010-05-26 Orlando Luongo , Hernando Quevedo

There are non-radial null geodesics emanating from the shell focusing singularity formed at the symmetric center in a spherically symmetric dust collapse. In this article, assuming the self-similarity in the region filled with the dust…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Ken-ichi Nakao , Naoki Kobayashi , Hideki Ishihara

In this essay we argue that once quantum gravitational effects change the classical geometry of a black hole and remove the curvature singularity, the black hole would not evaporate entirely but approach a remnant. In a modified…

General Relativity and Quantum Cosmology · Physics 2015-06-16 Li Xiang , Yi Ling , You Gen Shen

We consider a gravastar model made of anisotropic dark energy with an infinitely thin spherical shell of a perfect fluid with the equation of state $p = (1-\gamma)\sigma$ with an external de Sitter-Schwarzschild region. It is found that in…

General Relativity and Quantum Cosmology · Physics 2015-03-19 R. Chan , M. F. A. da Silva , P. Senna , J. F. Villas da Rocha

We present a general form for the solution of an expanding general-relativistic Friedmann universe that encounters a singularity at finite future time. The singularity occurs in the material pressure and acceleration whilst the scale…

General Relativity and Quantum Cosmology · Physics 2009-11-10 John D. Barrow

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 discuss the question of whether the existence of singularities is an intrinsic property of 4D spacetime. Our hypothesis is that singularities in 4D are induced by the separation of spacetime from the other dimensions. We examine this…

General Relativity and Quantum Cosmology · Physics 2007-05-23 J. Ponce de Leon

The initial value problem is well-defined on a class of spacetimes broader than the globally hyperbolic geometries for which existence and uniqueness theorems are traditionally proved. Simple examples are the time-nonorientable spacetimes…

General Relativity and Quantum Cosmology · Physics 2007-05-23 John L. Friedman

In this paper, we initiate the study of the instability of naked singularities without symmetries. In a series of papers, Christodoulou proved that naked singularities are not stable in the context of the spherically symmetric Einstein…

General Relativity and Quantum Cosmology · Physics 2018-03-13 Junbin Li , Jue Liu

We present a complete study of the geodesics around naked singularities in AdS$_3$, the three-dimensional anti-de Sitter spacetime. These stationary spacetimes, characterized by two conserved charges --mass and angular momentum--, are…

High Energy Physics - Theory · Physics 2019-07-24 Cristián Martínez , Nicolás Parra , Nicolás Valdés , Jorge Zanelli

We study the linearised stability of the nakedly singular negative mass Schwarzschild solution against gravitational perturbations. There is a one parameter family of possible boundary conditions at the singularity. We give a precise…

High Energy Physics - Theory · Physics 2009-10-07 Gary W. Gibbons , Sean A. Hartnoll , Akihiro Ishibashi

We investigate the occurrence of naked singularities in the spherically symmetric, plane symmetric and cylindrically symmetric collapse of charged null fluid in an anti-de Sitter background. The naked singularities are found to be strong in…

General Relativity and Quantum Cosmology · Physics 2008-11-26 S. G. Ghosh

In this article, a cylindrical symmetry and static solution of the Einstein's field equations, was presented. The space-time is conformally flat, regular everywhere except on the symmetry axis where it possesses a naked curvature…

General Physics · Physics 2018-04-18 Faizuddin Ahmed , Farook Rahaman

The existence and nature of singularities in locally spatially homogeneous solutions of the Einstein equations coupled to various phenomenological matter models is investigated. It is shown that, under certain reasonable assumptions on the…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Alan D. Rendall

We analyze solutions of Chamseddine's topological gravity in four space-time dimensions and discover various black hole solutions with(out) torsion as well as those that describe naked singularities. Because all of the solutions belong to…

High Energy Physics - Theory · Physics 2024-12-03 B. Cvetković , D. Simić

The spherical gravitational collapse of a compact packet consisting of perfect fluid is studied. The spacetime outside the fluid packet is described by the out-going Vaidya radiation fluid. It is found that when the collapse has continuous…

General Relativity and Quantum Cosmology · Physics 2009-10-31 J. F. Villas da Rocha , Anzhong Wang , N. O. Santos

We study null and timelike constant radii geodesics in the environment of an over-spinning putative Kerr-type naked singularity. We are particularly interested in two topics: first, the differences of the shadows of the naked rotating…

General Relativity and Quantum Cosmology · Physics 2024-02-20 Aydin Tavlayan , Bayram Tekin

We study the gravitational collapse of Type I matter field in $N$ dimensional spacetime with radial pressure $p_{r}$ as a function of $r $. We find that for a given smooth initial data set satisfying physical requirements, naked…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. B. Sarwe , R. V. Saraykar

The causal character of the zero-areal-radius (R=0) singularity in spherically symmetric spacetimes is studied. By using the techniques of the qualitative behaviour of dynamic systems, we are able to present the most comprehensive scheme so…

General Relativity and Quantum Cosmology · Physics 2012-04-23 Francesc Fayos , Ramon Torres