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Related papers: Sudden Future Singularities

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We discuss whether the future extrapolation of the present cosmological state may lead to a singularity even in case of "conventional" (negative) pressure of the dark energy field, namely $w=p/\rho \geq -1$. The discussion is based on an…

General Relativity and Quantum Cosmology · Physics 2009-11-10 M. Gasperini

We investigate self-similar solutions which are asymptotic to the Friedmann universe at spatial infinity and contain a scalar field with potential. The potential is required to be exponential by self-similarity. It is found that there are…

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

An oscillating universe cycles through a series of expansions and contractions. We propose a model in which ``phantom'' energy with a supernegative pressure ($p < - \rho$) grows rapidly and dominates the late-time expanding phase. The…

Astrophysics · Physics 2008-03-29 Katherine Freese , Matthew G. Brown , William H. Kinney

A theory of exponential modified gravity which explains both early-time inflation and late-time acceleration, in a unified way, is proposed. The theory successfully passes the local tests and fulfills the cosmological bounds and,…

High Energy Physics - Theory · Physics 2011-04-22 E. Elizalde , S. Nojiri , S. D. Odintsov , L. Sebastiani , S. Zerbini

An anthropic explanation for evident smallness of the value of the dark energy implies the existence of a time-dependent component of the scalar field, serving, together with a negative-valued cosmological constant, as one of two components…

General Relativity and Quantum Cosmology · Physics 2020-01-08 A. A. Yurova , A. V. Yurov , V. A. Yurov

We prove that a homogeneous and isotropic universe containing a scalar field with a power-law potential, $V(\phi )=A\phi ^{n}$, with $0<n<1$ and $A>0$ always develops a finite-time singularity at which the Hubble rate and its first…

General Relativity and Quantum Cosmology · Physics 2015-04-16 John D. Barrow , Alexander A. H. Graham

We study all four types of finite-time future singularities emerging in late-time accelerating (effective quintessence/phantom) era from $\mathcal{F}(R,G)$-gravity, where $R$ and $G$ are the Ricci scalar and the Gauss-Bonnet invariant,…

High Energy Physics - Theory · Physics 2014-11-20 Kazuharu Bamba , Sergei D. Odintsov , Lorenzo Sebastiani , Sergio Zerbini

We address the question whether a singularity in a three-dimensional incompressible inviscid fluid flow can occur in finite time. Analytical considerations and numerical simulations suggest high-symmetry flows being a promising candidate…

Fluid Dynamics · Physics 2012-10-10 Tobias Grafke , Rainer Grauer

It is shown that the tunneling effect in quantum cosmology is possible not only at the very beginning or the very end of the evolution, but also at the moment of maximum expansion of the universe. A positive curvature expanding Friedmann…

General Relativity and Quantum Cosmology · Physics 2009-10-28 M. P. Dabrowski , A. L. Larsen

We investigate models of future finite-time singularities in $f(T)$ theory, where $T$ is the torsion scalar. The algebraic function $f(T)$ is put as the teleparallel term $T$ plus an arbitrary function $g(T)$. A suitable expression of the…

General Relativity and Quantum Cosmology · Physics 2013-03-26 M. R. Setare , M. J. S. Houndjo

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

We review finite-time future singularities in modified gravity. We reconstruct an explicit model of modified gravity realizing a crossing of the phantom divide and show that the Big Rip singularity appears in the modified gravitational…

High Energy Physics - Theory · Physics 2009-06-23 Kazuharu Bamba

In the recent literature it has been shown that the $H_0$ tension may be eliminated if an abrupt physics transition changed the Cepheid parameters in the near past of the Universe, nearly $70-150\,$Myrs ago. In this letter we stress the…

General Relativity and Quantum Cosmology · Physics 2022-02-15 S. D. Odintsov , V. K. Oikonomou

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 consider a four-dimensional flat-space Friedman universe, which is filled with two interacting ideal fluids (the coupling of dark energy with dark matter of special form). The gravitational equations of motion are solved. It is shown…

High Energy Physics - Theory · Physics 2009-09-07 A. V. Timoshkin

When Einstein's equations for an asymptotically flat, vacuum spacetime are reexpressed in terms of an appropriate conformal metric that is regular at (future) null infinity, they develop apparently singular terms in the associated conformal…

General Relativity and Quantum Cosmology · Physics 2009-06-01 Vincent Moncrief , Oliver Rinne

The ultimate fate of life in a universe with accelerated expansion is considered. Previous work showed that life cannot go on indefinitely in a universe dominated by a cosmological constant. In this paper we consider instead other models of…

Astrophysics · Physics 2016-08-30 Katherine Freese , William H. Kinney

Based on the conjecture that rather than the second law of thermodynamics inevitably be breached as matter approaches a big crunch or a black hole singularity, the order of events should reverse, a model of the universe that resolves a…

General Physics · Physics 2007-05-23 Peter Lynds

Recently it was found that dark energy in the form of phantom generalized Chaplygin gas may lead to a new form of the cosmic doomsday, the big freeze singularity. Like the big rip singularity, the big freeze singularity would also take…

Astrophysics · Physics 2009-11-13 Artyom V. Yurov , Artyom V. Astashenok , Pedro F. Gonzalez-Diaz

By studying a modified Friedmann equation which arises in an extension of general relativity which accommodates a time-dependent fundamental length $L(t)$, we consider cosmological models where the scale factor diverges with an essential…

Astrophysics · Physics 2014-10-13 Paul H. Frampton , Tomo Takahashi
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