English
Related papers

Related papers: Dilatonic effects near naked singularities

200 papers

We consider, in 5 dimensions, the low energy effective action induced by heterotic string theory including the leading stringy correction of order alpha'. In the presence of a single positive tension flat brane, and an infinite extra…

High Energy Physics - Theory · Physics 2008-11-26 Pierre Binetruy , Christos Charmousis , Stephen C Davis , Jean-Francois Dufaux

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 what are the key physical features that cause the development of a naked singularity, rather than a black hole, as the end-state of spherical gravitational collapse. We show that sufficiently strong shearing effects near the…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Pankaj S. Joshi , Naresh Dadhich , Roy Maartens

We study a class of dilatonic deformations of asymptotically AdS_5 X S^5 geometry analytically and numerically. The spacetime is non-supersymmetric and suffers from a naked singularity. We propose that the causality bound may serve as a…

High Energy Physics - Theory · Physics 2009-11-10 Dongsu Bak , Michael Gutperle , Shinji Hirano , Nobuyoshi Ohta

d5 dilatonic gravity action with surface counterterms motivated by AdS/CFT correspondence and with contributions of brane quantum CFTs is considered around AdS-like bulk. The effective equations of motion are constructed. They admit two…

High Energy Physics - Theory · Physics 2009-09-17 S. Nojiri , S. D. Odintsov , K. E. Osetrin

The behaviors of quantum stress tensor for the scalar field on the classical background of spherical dust collapse is studied. In the previous works diverging flux of quantum radiation was predicted. We use the exact expressions in a 2D…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Hideo Iguchi , Tomohiro Harada

One of the fundamental unanswered questions in the general theory of relativity is whether ``naked'' singularities, that is singular events which are visible from infinity, may form with positive probability in the process of gravitational…

Analysis of PDEs · Mathematics 2016-09-07 Demetrios Christodoulou

We study singularities which can form in a spherically symmetric gravitational collapse of a general matter field obeying weak energy condition. We show that no energy can reach an outside observer from a null naked singularity. That means…

General Relativity and Quantum Cosmology · Physics 2010-02-17 Shrirang S. Deshingkar

We study strong gravitational lensing in a static, spherically symmetric, naked singularity spacetime, without a photon sphere. The nature of the singularity is found to be lightlike. We discuss the characteristic lensing features of this…

General Relativity and Quantum Cosmology · Physics 2020-09-25 Suvankar Paul

We present a novel example of a 2-dimensional space-time naked singularity. The solution has a gravity singularity and no-horizon. This example is only a toy model and as such its motivation is mathematical. In the physical sense it is very…

General Relativity and Quantum Cosmology · Physics 2015-11-19 J. Manuel Garcia-Islas

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

We study an analytical solution to the Einstein's equations in 2+1-dimensions, representing the self-similar collapse of a circularly symmetric, minimally coupled, massless, scalar field. Depending on the value of certain parameters, this…

General Relativity and Quantum Cosmology · Physics 2014-11-17 G. Oliveira-Neto

In this paper, we study the instability of naked singularities arising in the Einstein equations coupled with isothermal perfect fluid. We show that the spherically symmetric self-similar naked singularities of this system, are unstable to…

General Relativity and Quantum Cosmology · Physics 2025-05-28 Junbin Li , Xi-Ping Zhu

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

It is shown that among the four classes of the static spherically symmetric solution of the vacuum Brans-Dicke theory of gravity only two are really independent. Further by matching exterior and interior (due to physically reasonable…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Arunava Bhadra , Kabita Sarkar

Gravitational collapse is one of the most striking phenomena in gravitational physics. The cosmic censorship conjecture has provided strong motivation for researches in this field. In the absence of general proof for the censorship, many…

General Relativity and Quantum Cosmology · Physics 2009-09-29 Tomohiro Harada

We use the Dirac equation coupled to a background metric to examine what happens to quantum mechanical observables like the probability density and the radial current in the vicinity of a naked singularity of the Reissner-Nordstr\"{o}m…

General Relativity and Quantum Cosmology · Physics 2011-04-20 D. Batic , M. Nowakowski

Solutions describing the gravitational collapse of asymptotically flat cylindrical and prolate shells of (null) dust are shown to admit globally naked singularities.

General Relativity and Quantum Cosmology · Physics 2009-11-07 Brien C. Nolan

A simple trace-coupled Galileon model is shown to admit spherically symmetric static solutions with naked spacetime curvature singularities.

High Energy Physics - Theory · Physics 2015-06-11 Thomas L. Curtright

There are many solutions to the Einstein field equations that demonstrate naked singularity (NS) formation after regular evolution. It is possible, however, that such a quantum effect as particle creation prevents NSs from forming. We…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Umpei Miyamoto , Hideki Maeda , Tomohiro Harada