English
Related papers

Related papers: Singularities in FLRW Spacetimes

200 papers

In this paper we have discussed geodesics and the motion of test particle in the gravitational field of noncommutative charged black hole spacetime. The motion of massive and massless particle have been discussed seperately. A comparative…

General Relativity and Quantum Cosmology · Physics 2015-07-14 Piyali Bhar , Farook Rahaman , Ritabrata Biswas , U. F. Mondal

Using a second law of complexity, we prove a black hole singularity theorem. By introducing the notion of trapped extremal surfaces, we show that their existence implies null geodesic incompleteness inside globally hyperbolic black holes.…

High Energy Physics - Theory · Physics 2025-07-31 Vyshnav Mohan

A regularization procedure has been recently suggested for regularizing Big Bang singularities in Friedmann-Lemaitre-Robertson-Walker (FLRW) spacetimes. We argue that this procedure is only appliable to one case of Big Bang singularities…

General Relativity and Quantum Cosmology · Physics 2016-03-22 L. Fernández-Jambrina

We investigate the effect of higher-order curvature terms, specifically Gauss-Bonnet terms, on spacetime singularities in five dimensions. For FLRW cosmologies, we demonstrate that Gauss-Bonnet terms can replace the Big Bang/Crunch with a…

General Relativity and Quantum Cosmology · Physics 2026-02-24 Tariq Allaithy , Adel Awad , Mohamed Hany Radwan , Mohsen Zahran

Recently a new type of cosmological singularity has been postulated for infinite barotropic index $w$ in the equation of state $p=w \rho$ of the cosmological fluid, but vanishing pressure and density at the singular event. Apparently the…

General Relativity and Quantum Cosmology · Physics 2011-09-28 L. Fernández-Jambrina

The celebrated geodesic congruence equation of Raychaudhuri, together with the resulting singularity theorems of Penrose and Hawking that it enabled, yield a highly general set of conditions under which a spacetime (or, more generically, a…

General Relativity and Quantum Cosmology · Physics 2023-03-14 Jonathan Gorard

We hereby address the cosmological singularity problem in a general gravitational theory invariant under Weyl conformal transformations. In particular, we focus on the Bianchi IX spacetime and we show that both the initial (big bang) and…

General Relativity and Quantum Cosmology · Physics 2026-01-21 Jiale Gu , Leonardo Modesto , Cosimo Bambi

Space-time--time is a natural hybrid of Kaluza's five-dimensional geometry and Weyl's conformal space-time geometry. Translations along the secondary time dimension produce the electromagnetic gauge transformations of Kaluza--Klein theory…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Homer G. Ellis

It is generally assumed that naked singularities must be physically excluded, as they could otherwise introduce unpredictable influences in their future null cones. Considering geodesics for a naked Reissner-Nordstrom singularity, it is…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Asghar Qadir , Azad A. Siddiqui

The condition for the existence of self-gravitational solitary waves (SGSWs), and their polarity in any astrophysical compact object are theoretically found for the first time. The pseudo-potential approach, which is valid for arbitrary…

Plasma Physics · Physics 2017-06-13 A. A. Mamun

The gravitational collapse of a thick cylindrical shell of dust matter is investigated. It is found that a spacetime singularity forms on the symmetry axis and that it is necessarily naked, i.e., observable in principle. We propose a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Ken-ichi Nakao , Yasunari Kurita , Yoshiyuki Morisawa , Tomohiro Harada

The gravitational collapse of an infinite cylindrical thin shell of generic matter in an otherwise empty spacetime is considered. We show that geometries admitting two hypersurface orthogonal Killing vectors cannot contain trapped surfaces…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Sergio M. C. V. Goncalves

The problem of classifying boundary points of space-time, for example singularities, regular points and points at infinity, is an unexpectedly subtle one. Due to the fact that whether or not two boundary points are identified or even…

General Relativity and Quantum Cosmology · Physics 2018-11-14 Ingrid Irmer

This paper is an attempt to classify finite-time singularities of PDEs. Most of the problems considered describe free-surface flows, which are easily observed experimentally. We consider problems where the singularity occurs at a point, and…

Analysis of PDEs · Mathematics 2007-11-06 Jens Eggers , Marco A. Fontelos

Milne-like spacetimes are a class of $k = -1$ FLRW spacetimes which admit continuous spacetime extensions through the big bang. In a previous paper [30], it was shown that the cosmological constant appears as an initial condition for…

General Relativity and Quantum Cosmology · Physics 2022-07-27 Eric Ling

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

Recently Ho$\breve{r}$ava proposed a non-relativistic renormalisable theory of gravitation. When restricted to satisfy the condition of detailed balance, this theory is intimately related to topologically massive gravity in three…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Juhua Chen , Yongjiu Wang

In this work we review the study of singularities in Poincar\'e gauge theories of gravity. Since one of the most recent studies uses the appearance of black hole regions of arbitrary dimension as an indicator of singular behaviour, we also…

General Relativity and Quantum Cosmology · Physics 2019-03-21 J. A. R. Cembranos , J. Gigante Valcarcel , F. J. Maldonado Torralba

Seminar held at JINR, Dubna, May 15, 2012. In General Relativity, spacetime singularities raise a number of problems, both mathematical and physical. One can identify a class of singularities - with smooth but degenerate metric - which,…

General Relativity and Quantum Cosmology · Physics 2012-07-31 Ovidiu Cristinel Stoica

A study is undertaken of the gravitational collapse of spherically symmetric thick shells admitting a homothetic Killing vector field under the assumption that the energy momentum tensor corresponds to the absence of a pure outgoing…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Brien C. Nolan