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Related papers: Cosmological singularities in FLRW spacetimes

200 papers

The Born-Infeld determinantal gravity has been recently proposed as a way to smooth the Big Bang singularity. This theory is formulated on the Weitzenbock space-time and the teleparallel representation is used instead of the standard…

General Relativity and Quantum Cosmology · Physics 2014-12-24 Mariam Bouhmadi-Lopez , Che-Yu Chen , Pisin Chen

Solutions of the Friedmann-Lemaitre cosmological equations of general relativity have been found with finite-time singularities that are everywhere regular, have regular Hubble expansion rate, and obey the strong-energy conditions but…

General Relativity and Quantum Cosmology · Physics 2016-11-15 John D. Barrow , S. Cotsakis , A. Tsokaros

We review the accelerating (mainly, dark energy) cosmologies in modified gravity. Special attention is paid to cosmologies leading to finite-time future singularities in $F(R)$, $F(G)$ and $\mathcal{F}(R,G)$ modified gravities. The removal…

General Relativity and Quantum Cosmology · Physics 2013-02-21 Kazuharu Bamba , Shin'ichi Nojiri , Sergei D. Odintsov

Interest in cosmological singularities has remarkably grown in recent times, particularly on future singularities with the discovery of late-time acceleration of the universe and dark energy. Recent work has seen a proper classification of…

General Relativity and Quantum Cosmology · Physics 2022-10-11 Oem Trivedi

We consider here the genericity aspects of spacetime singularities that occur in cosmology and in gravitational collapse. The singularity theorems (that predict the occurrence of singularities in general relativity) allow the singularities…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Pankaj S. Joshi

In this comment we discuss big rip singularities occurring in typical phantom models by violation of the weak energy condition. After that, we compare them with future late-time singularities arising in models where the scale factor ends in…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Luis P. Chimento , Ruth Lazkoz

While the use of numerical general relativity for modeling astrophysical phenomena and compact objects is commonplace, the application to cosmological scenarios is only just beginning. Here, we examine the expansion of a spacetime using the…

General Relativity and Quantum Cosmology · Physics 2016-06-27 John T. Giblin , James B. Mertens , Glenn D. Starkman

The occurrence of singularities where spacetime curvature becomes infinite and geodesic evolution breaks down are inevitable events in classical general relativity (GR) unless one chooses an exotic matter violating weak energy condition.…

General Relativity and Quantum Cosmology · Physics 2024-11-05 Bao-Fei Li , Parampreet Singh

In this expository article we describe the attempt of defining cosmological singularities and we discuss their meaning in classical and quantum cosmology.

Popular Physics · Physics 2007-05-23 Giampiero Esposito

The paper deals with $f(R)$ gravity theory in the background of inhomogeneous FLRW--type space time model. With proper choice of the inhomogeneous metric function it is possible to have an emergent scenario for the $f(R)$--cosmology.…

General Relativity and Quantum Cosmology · Physics 2018-11-14 Dipanjana Das , Sourav Dutta , Subenoy Chakraborty

We investigate the FLRW type cosmology of the Induced Dark Energy model and illustrate that the extra terms emerging from the fifth dimension can play the role of dark energy. The model predicts the expansion with deceleration at early time…

General Relativity and Quantum Cosmology · Physics 2017-12-27 Amirfarshad Bahrehbakhsh

In this work, we study the possibility of finite-time future cosmological singularities appearing in $f(R,T)$ gravity, where $R$ is the Ricci scalar and $T$ is the trace of the stress-energy tensor. We present the theory in both the…

General Relativity and Quantum Cosmology · Physics 2022-05-10 Tiago B. Gonçalves , João Luís Rosa , Francisco S. N. Lobo

We discuss recent developments related to certain blow up methods suitable for the analysis of cosmological singularities and asymptotics. We review results obtained in a variety of currently popular themes and describe ongoing research…

General Relativity and Quantum Cosmology · Physics 2013-10-11 Spiros Cotsakis

We consider different aspects of the problem of cosmological singularity such as the BKL oscillatory approach to the singularity, the new features of the cosmological dynamics in the neighbourhood of the singularity in multidimensional and…

General Relativity and Quantum Cosmology · Physics 2010-12-17 A. Yu. Kamenshchik

We will make a comparison between the dynamics of spherical gravitational collapse for a perturbed FLRW universe to first order in the context of general relativity, with the corresponding results obtained for the gravitational collapse…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-12 César Peralta , Leonardo Castañeda

Big bang of the Friedmann-Robertson-Walker (FRW)-brane universe is studied. In contrast to the spacelike initial singularity of the usual FRW universe, the initial singularity of the FRW-brane universe is point-like from the viewpoint of…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Hideki Ishihara

FLRW models filled with just dark energy are shown to have a finite past, since causal geodesics cannot be extended beyond a certain proper time. It is shown that curvature measured along causal geodesics becomes infinity on travelling to…

General Relativity and Quantum Cosmology · Physics 2009-03-31 L. Fernández-Jambrina

We consider perturbative modifications of the Friedmann equations in terms of energy density corresponding to modified theories of gravity proposed as an alternative route to comply with the observed accelerated expansion of the universe.…

General Relativity and Quantum Cosmology · Physics 2015-05-13 L. Fernández-Jambrina , R. Lazkoz

In a recent series of papers Endean examines the properties of spatially homogeneous and isotropic (FLRW) cosmological models filled with dust in the ``conformally flat spacetime presentation of cosmology'' (CFS cosmology). This author…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Laurent Querella

We show the existence of an infinite family of finite-time singularities in isotropically expanding universes which obey the weak, strong, and dominant energy conditions. We show what new type of energy condition is needed to exclude them…

General Relativity and Quantum Cosmology · Physics 2009-11-10 John D. Barrow , Christos G. Tsagas