English
Related papers

Related papers: Naked Singularities as Particle Accelerators II

200 papers

Spherically symmetric inhomogeneous dust collapse has been studied in higher dimensional space-time and the factors responsible for the appearance of a naked singularity are analyzed in the region close to the centre for the marginally…

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

Conditions under which gravity coupled to self interacting scalar field determines singularity formation are found and discussed. It is shown that, under a suitable matching with an external space, the boundary, if collapses completely, may…

General Relativity and Quantum Cosmology · Physics 2010-11-05 Roberto Giambó

We consider here the question if it is possible to recover cosmic censorship when a transition is made to higher dimensional spacetimes, by studying the spherically symmetric dust collapse in an arbitrary higher spacetime dimension. It is…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Rituparno Goswami , Pankaj S Joshi

In this paper, we derive the solutions of orbit equations for a class of naked singularity spacetimes, and compare these with timelike orbits, that is, particle trajectories in the Schwarzschild black hole spacetime. The Schwarzschild and…

General Relativity and Quantum Cosmology · Physics 2019-12-11 Parth Bambhaniya , Ashok B. Joshi , Dipanjan Dey , Pankaj S. Joshi

We analyse here the gravitational collapse of directed null radiation in a background with a constant potential such as one produced by a star system like galaxy in which the collapsing object is immersed. Both naked singularities and black…

General Relativity and Quantum Cosmology · Physics 2009-10-31 S. Jhingan , N. Dadhich , P. S. Joshi

We discuss different kinds of Killing horizons possible in static, spherically symmetric configurations and recently classified as "usual", "naked" and "truly naked" ones depending on the near-horizon behavior of transverse tidal forces…

General Relativity and Quantum Cosmology · Physics 2009-02-23 K. A. Bronnikov , E. Elizalde , S. D. Odintsov , O. B. Zaslavskii

We study the occurrence of naked singularities in the spherically symmetric collapse of a charged null fluid in an expanding deSitter background - a piece of charged Vaidya-deSitter spacetime. The necessary conditions for the formation of a…

General Relativity and Quantum Cosmology · Physics 2009-10-31 A. Beesham , S. G. Ghosh

The phase space corresponding to a particular four-parameter family of initial data for the gravitational collapse of a spherically symmetric dust cloud is investigated. In a certain limit of the parameters, this family reproduces the case…

General Relativity and Quantum Cosmology · Physics 2015-03-20 Néstor Ortiz

The asymptotic behavior of geometry near the boundary of maximal Cauchy development is studied using a perturbative method, which at the zeroth order reduces Einstein's equations to an exactly solvable set of equations---Einstein's…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Boro Grubisic

Electromagnetic waves propagating in the background provided by a spacetime hosting a strong curvature, naked singularity, are fully studied. The analysis is performed not only in the realm of geometrical optics -- which, not surprisingly,…

General Relativity and Quantum Cosmology · Physics 2025-04-25 Franco Fiorini , Santiago Hernandez , Juan Manuel Paez

We investigate the end state of the gravitational collapse of an inhomogeneous dust cloud in higher dimensional space-time. The naked singularities are shown to be developing as the final outcome of non-marginally bound collapse. The naked…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Ujjal Debnath , Subenoy Chakraborty

We analyze the redshift suffered by photons originating from an external source, traversing a collapsing dust cloud and finally being received by an asymptotic observer. In addition, we study the shadow that the collapsing cloud casts on…

General Relativity and Quantum Cosmology · Physics 2015-09-10 Néstor Ortiz , Olivier Sarbach , Thomas Zannias

We study the causal structure of dynamical charged black holes, with a sufficient number of massless fields, using numerical simulations. Neglecting Hawking radiation, the inner horizon is a null Cauchy horizon and a curvature singularity…

General Relativity and Quantum Cosmology · Physics 2014-11-18 Sungwook E. Hong , Dong-il Hwang , Ewan D. Stewart , Dong-han Yeom

We consider particle collision inside the inner horizon of the Reissner-Nordstrom metric in the so-called R region. We show that there exist scenario in which the enrgy in the center of mass frame grows unbounded. In contrast to the…

General Physics · Physics 2026-03-24 A. V. Toporensky , O. B. Zaslavskii

Naked singularities (NkS) are solutions to the Einstein field equations that violate the cosmic censorship conjecture. Recent studies indicate that these objects may serve as compelling mimickers of black hole shadows. In this work, we…

High Energy Astrophysical Phenomena · Physics 2025-09-12 Akhil Uniyal , Indu K. Dihingia , Yosuke Mizuno , Włodek Kluźniak

Gravitational collapse of the Brans-Dicke scalar field with non-zero potential in the presence of matter fluid obeying the barotropic equation of state, $p=w\rho$ is studied. Utilizing the concept of expansion parameter, it is seen that the…

General Relativity and Quantum Cosmology · Physics 2014-11-20 A. H. Ziaie , K. Atazadeh , Y. Tavakoli

It is known that the gravitational collapse of cold dark matter leads to infinite-density caustics that seed the primordial dark-matter halos in the large-scale structure. The development of these caustics begins, generically, as an almost…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-25 Cornelius Rampf , Uriel Frisch , Oliver Hahn

We calculate the quantum stress tensor for a massless scalar field in the 2-d self-similar spherical dust collapse model which admits a naked singularity. We find that the outgoing radiation flux diverges on the Cauchy horizon. This may…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Sukratu Barve , T. P. Singh , Cenalo Vaz , Louis Witten

The recently discovered so-called BSW effect consists in the unbound growth of the energy E_{c.m.} in the centre of mass frame of two colliding particles near the black hole horizon. We consider a new type of the corresponding scenario when…

General Relativity and Quantum Cosmology · Physics 2015-06-04 O. B. Zaslavskii

For a wide class of spherically symmetric naked singularities there is a sphere within which gravity is effectively repulsive. In such spacetimes accreting matter cannot reach the singularity and will instead form a levitating atmosphere,…

General Relativity and Quantum Cosmology · Physics 2021-09-07 Ronaldo S. S. Vieira , Włodek Kluźniak