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Related papers: Sudden future singularities in FLRW cosmologies

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The fundamental singularity theorem of FLRW cosmologies assumes that the matter content in the cosmological model obeys the strong energy condition along with a nonpositive cosmological constant which gives rise to an irrotational geodesic…

General Relativity and Quantum Cosmology · Physics 2016-09-12 Ikjyot Singh Kohli

In this paper we analyze the effect of recently proposed classes of sudden future singularities on causal geodesics of FLRW spacetimes. Geodesics are shown to be extendible and just the equations for geodesic deviation are singular,…

General Relativity and Quantum Cosmology · Physics 2009-11-10 L. Fernández-Jambrina , Ruth Lazkoz

We argue that many future-eternal inflating spacetimes are likely to violate the weak energy condition. It is possible that such spacetimes may not enforce any of the known averaged conditions either. If this is indeed the case, it may open…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Arvind Borde , Alex Vilenkin

Exploiting the existence of two "cosmological" constants, one associated with the classical Lovelock theorem and one with the vacuum energy density, we argue, in a model independent way, that in spatially closed FLRW cosmologies with a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Benjamin K. Tippett , Kayll Lake

We find that sudden future singularities may also appear in spatially inhomogeneous Stephani models of the universe. They are temporal pressure singularities and may appear independently of the spatial finite density singularities already…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Mariusz P. Dcabrowski

In general relativity, the energy conditions are invoked to restrict general energy-momentum tensors $T_{\mu\nu}$ in different frameworks, and to derive general results that hold in a variety of general contexts on physical grounds. We show…

Astrophysics · Physics 2008-11-26 J. Santos , J. S. Alcaniz , N. Pires , M. J. Reboucas

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

In this talk we review the appearance of new types of singularities (big rip, sudden singularities...) in FLRW cosmological models that have arisen on considering explanations for accelerated expansion of our universe.

General Relativity and Quantum Cosmology · Physics 2010-01-19 L. Fernandez-Jambrina , R. Lazkoz

In this talk we analyze the effect of recently proposed classes of sudden future singularities on causal geodesics of FLRW spacetimes. Geodesics are shown to be extendible and just the equations for geodesic deviation are singular, although…

General Relativity and Quantum Cosmology · Physics 2009-11-13 L. Fernández-Jambrina , R. Lazkoz

In this work we consider a family of cosmological models featuring future singularities. This type of cosmological evolution is typical of dark energy models with an equation of state violating some of the standard energy conditions (e.g.…

General Relativity and Quantum Cosmology · Physics 2016-12-21 Jose Beltran Jimenez , Ruth Lazkoz , Diego Saez-Gomez , Vincenzo Salzano

We explore the dynamics of FLRW cosmologies which consist of dark matter, radiation and dark energy with a quadratic equation of state. Standard cosmological singularities arise due to energy conditions which are violated by dark energy,…

General Relativity and Quantum Cosmology · Physics 2023-05-19 Molly Burkmar , Marco Bruni

Current observational evidence does not yet exclude the possibility that dark energy could be in the form of phantom energy. A universe consisting of a phantom constituent will be driven toward a drastic end known as the `Big Rip'…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Hoda Ghodsi , Martin A. Hendry , Mariusz P. Dabrowski , Tomasz Denkiewicz

Here, an accelerated phantom model for the late universe is explored, which is free from future singularity. It is interseting to see that this model exhibits strong curvature for all time in future, unlike models with `big-rip singularity'…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. K. Srivastava

We study the future cosmological singularities in the framework of massive gravity and minimal massive bigravity theory. In this regards, we consider the possible classes of finite-time future singularities such as sudden, big rip, big…

General Relativity and Quantum Cosmology · Physics 2022-01-27 M. Mousavi , K. Atazadeh

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

We consider the problem of describing the asymptotic behaviour of \textsc{FRW} universes near their spacetime singularities in general relativity. We find that the Bel-Robinson energy of these universes in conjunction with the Hubble…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Spiros Cotsakis , Ifigeneia Klaoudatou

We discuss various types of exotic (non-standard) singularities in the Universe: a Big-Rip (BR or type I), a Sudden Future Singularity (SFS or type II), a Generalized Sudden Future Singularity, a Finite Scale Factor singularity (FSF or type…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Mariusz P. Dabrowski , Tomasz Denkiewicz

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

We show that a singularity can occur at a finite future time in an expanding Friedmann universe even when the density is positive and the density plus the sum of the principal pressures is positive. Explicit examples are constructed and a…

General Relativity and Quantum Cosmology · Physics 2009-11-10 John D. Barrow

We show that cosmological sudden singularities that respect the energy conditions can occur at finite times in Brans-Dicke and more general scalar-tensor theories of gravity. We construct these explicitly in the Friedmann universes.…

General Relativity and Quantum Cosmology · Physics 2020-02-21 John D. Barrow
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