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Related papers: Can we see naked singularities?

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A spacetime singularity, identified by the existence of incomplete causal geodesics in the spacetime, is called a (Tipler) strong curvature singularity if the volume form acting on independent Jacobi fields along causal geodesics vanishes…

General Relativity and Quantum Cosmology · Physics 2025-02-03 Kharanshu N. Solanki , Karim Mosani , Omkar Deshpande , Pankaj S. Joshi

Motivated by the endeavors of Li Xiang and You-Gen Shen on naked singularities, we investigate the validity of the cosmic censorship conjecture in the context of generalized uncertainty principle. In particular, upon considering both linear…

High Energy Physics - Theory · Physics 2022-08-11 Elias C. Vagenas , Ahmed Farag Ali , Hassan Alshal

For any asymptotically flat spacetime with a suitable causal structure obeying (a weak form of) Penrose's cosmic censorship conjecture and satisfying conditions guaranteeing focusing of complete null geodesics, we prove that active…

General Relativity and Quantum Cosmology · Physics 2010-04-06 G. J. Galloway , E. Woolgar

In this paper we study gravitational lensing in the strong field limit from the perspective of cosmic censorship, to investigate whether or not naked singularities, if at all they exist in nature, can be distinguished from black holes. We…

General Relativity and Quantum Cosmology · Physics 2012-09-21 Satyabrata Sahu , Mandar Patil , D. Narasimha , Pankaj S. Joshi

We study the occurrence and nature of naked singularities for a dust model with non-zero cosmological constant in ($n+2$)-dimensional Szekeres space-times (which possess no Killing vectors) for $n\geq 2$. We find that central shell-focusing…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Ujjal Debnath , Subenoy Chakraborty , John D. Barrow

Metrics representing black holes in General Relativity may exhibit naked singularities for certain values of their parameters. This is the case for super-extremal ($J^2 > M>0$) Kerr and super-extremal ($|Q|>M>0$) Reissner-N\"ordstrom…

General Relativity and Quantum Cosmology · Physics 2009-04-24 Gustavo Dotti , Reinaldo J. Gleiser , Jorge Pullin , Ignacio F. Ranea-Sandoval , Héctor Vucetich

In this paper we study the quasi-spherical gravitational collapse of (n+2) dimensional Szekeres space-time. The nature of the central shell focusing singularity so formed is analyzed by studying both the radial null and time-like geodesic…

Mathematical Physics · Physics 2009-11-10 Ujjal Debnath , Subenoy Chakraborty

We test the chronology protection conjecture in classical general relativity by investigating finitely vicious space-times. First we present singularity theorems in finitely vicious space-times by imposing some restrictions on the…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Kengo Maeda , Akihiro Ishibashi , Makoto Narita

There are models of gravitational collapse in classical general relativity which admit the formation of naked singularities as well as black holes. These include fluid models as well as models with scalar fields as matter. Even if fluid…

General Relativity and Quantum Cosmology · Physics 2007-05-23 T. P. Singh

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

Considering the evolution of a perfect fluid with self-similarity of the second kind, we have found that an initial naked singularity can be trapped by an event horizon due to collapsing matter. The fluid moves along time-like geodesics…

General Relativity and Quantum Cosmology · Physics 2012-10-25 C. F. C. Brandt , R. Chan , M. F. A. da Silva , J. F. Villas da Rocha

The global visibility of a singularity as an end state of the gravitational collapse of a spherically symmetric pressureless cloud is investigated. We show the existence of a non-zero measured set of parameters: the total mass and the…

General Relativity and Quantum Cosmology · Physics 2022-11-15 Karim Mosani , Dipanjan Dey , Pankaj S. Joshi

We present here an overview of our basic understanding and recent developments on spacetime singularities in the Einstein theory of gravity. Several issues related to physical significance and implications of singularities are discussed.…

General Relativity and Quantum Cosmology · Physics 2015-06-17 Pankaj S. Joshi

Cosmic censorship conjecture takes a pivotal status in general relativity. We demonstrate that quantum effects, Hawking effect together with Shwinger effect inevitably lead to violation of cosmic censorship. We find that naked singularity…

General Relativity and Quantum Cosmology · Physics 2025-07-01 Yang Huang , Hongsheng Zhang

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

Gravitational collapse of a spherically symmetric cloud has been extensively studied to investigate the nature of resulting singularity. However, there has been considerable debate about the admissibility of certain initial density…

General Relativity and Quantum Cosmology · Physics 2007-05-23 H. M. Antia

It is widely expected that generic black holes have a non-empty but weakly singular Cauchy horizon, due to mass inflation. Indeed this has been proven by the author in the spherical collapse of a charged scalar field, under decay…

General Relativity and Quantum Cosmology · Physics 2022-11-08 Maxime Van de Moortel

Spherically symmetric inhomogeneous dust collapse has been studied in higher dimensional space-time and appearance of naked singularity has been analyzed both for non-marginal and marginally bound cases. It has been shown that naked…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Ujjal Debnath , Subenoy Chakraborty

In this paper, we derive general conditions for a shadow to occur, without a photon sphere in a spacetime, caused by central nulllike or timelike naked singularities. Using these conditions, we propose classes of spacetimes which have…

General Relativity and Quantum Cosmology · Physics 2021-01-13 Dipanjan Dey , Rajibul Shaikh , Pankaj S. Joshi

In this note a time dependent spacetime is explored in the background of $f(R,T)$ gravity via the gravitational collapse of a massive star. The star is modelled by the Vaidya spacetime which is time dependent in nature. The coupling of…

General Relativity and Quantum Cosmology · Physics 2020-06-02 Prabir Rudra
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