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Related papers: Sudden Future Singularities

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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

In this paper we study the final fate of the universe in modified theories of gravity. As compared with general relativistic formulations, in these scenarios the Friedmann equation has additional terms which are relevant for low density…

General Relativity and Quantum Cosmology · Physics 2009-01-16 L. Fernández-Jambrina , Ruth Lazkoz

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

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

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

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

We discuss the constraints coming from current observations of type Ia supernovae on cosmological models which allow sudden future singularities of pressure (with the scale factor and the energy density regular). We show that such a sudden…

Astrophysics · Physics 2008-12-18 Mariusz P. Dabrowski , Tomasz Denkiewicz , Martin A. Hendry

We investigate the effects of quantum particle production on a classical sudden singularity occurring at fine time in a Friedmann universe. We use an exact solution to describe an initially radiation-dominated universe that evolves into a…

General Relativity and Quantum Cosmology · Physics 2012-07-06 John D. Barrow , Antonio B. Batista , Julio C. Fabris , M. J. S. Houndjo

Spacetime singularities have been discovered which are physically much weaker than those predicted by the classical singularity theorems. Geodesics evolve through them and they only display infinities in the derivatives of their curvature…

General Relativity and Quantum Cosmology · Physics 2015-12-09 John D. Barrow , Alexander A. H. Graham

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

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 consider finite-time, future (sudden or Big Rip type) singularities which may occur even when strong energy condition is not violated but equation of state parameter is time-dependent. Recently, example of such singularity has been…

High Energy Physics - Theory · Physics 2008-11-26 Shin'ichi Nojiri , Sergei D. Odintsov

We construct solutions of the Friedmann equations near a sudden singularity using generalized series expansions for the scale factor, the density, and the pressure of the fluid content. In this way, we are able to arrive at a solution with…

General Relativity and Quantum Cosmology · Physics 2013-01-29 John D. Barrow , S. Cotsakis , A. Tsokaros

We demonstrate the existence of sudden, finite-time, singularities, with constant scale factor, expansion rate and density, in expanding Bianchi type IX universes with free anisotropic pressures. A new type of non-simultaneous anisotropic…

General Relativity and Quantum Cosmology · Physics 2020-07-29 John D. Barrow

We consider the fate of future singularities in the effective dynamics of loop quantum cosmology. Non-perturbative quantum geometric effects which lead to $\rho^2$ modification of the Friedmann equation at high energies result in generic…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. Sami , Parampreet Singh , Shinji Tsujikawa

The properties of future singularities are investigated in the universe dominated by dark energy including the phantom-type fluid. We classify the finite-time singularities into four classes and explicitly present the models which give rise…

High Energy Physics - Theory · Physics 2009-09-17 Shin'ichi Nojiri , Sergei D. Odintsov , Shinji Tsujikawa

The discovery of accelerated expansion of the universe opened the possibility of new scenarios for the doom of our spacetime, besides aeternal expansion and a final contraction. In this paper we review the chances which may await our…

General Relativity and Quantum Cosmology · Physics 2022-03-01 L. Fernández-Jambrina , R. Lazkoz

By studying first a new decelerating sudden future singularity (SFS) universe we report finding a novel type of cosmological singularity which we dub a finite time pseudo-rip (FTPR) because unlike for a pseudo-rip, it happens in the finite…

General Relativity and Quantum Cosmology · Physics 2026-05-21 Mariusz P. Dąbrowski , Teodor Borislavov Vasilev

General relativity allows a variety of future singularities to occur in the evolution of the universe. At these future singularities, the universe will end in a singular state after a finite proper time and geometrical invariants of the…

General Relativity and Quantum Cosmology · Physics 2012-07-06 John D. Barrow , Antonio B. Batista , Giuseppe Dito , Julio C. Fabris , M. J. S. Houndjo

We verify the existence of Generalized Sudden Future Singularities (GSFS) in quintessence models with scalar field potential of the form $V(\phi)\sim \vert \phi\vert^n$ where $0<n<1$ and in the presence of a perfect fluid, both numerically…

General Relativity and Quantum Cosmology · Physics 2018-12-07 Andreas Lymperis
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