English
Related papers

Related papers: Worse than a big rip?

200 papers

In this paper, we investigate cosmological consequences of a scenario for recently reported accelerated expansion of the Universe, in which the generalized Chaplygin gas (GCG) along with the baryonic matter are responsible for this observed…

General Relativity and Quantum Cosmology · Physics 2017-05-24 Hamid Shabani

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

Cosmological singularity theorems such as that of Hawking and Penrose assume local curvature conditions as well as global ones like the existence of a compact (achronal) slice. Here, we prove a new singularity theorem for chronological…

General Relativity and Quantum Cosmology · Physics 2019-08-29 Martin Lesourd

We investigate a family of inhomogeneous and anisotropic gravitational fields exhibiting a future singularity at a finite value of the proper time. The studied spherically symmetric spacetimes are asymptotically Friedmann-Robertson-Walker…

General Relativity and Quantum Cosmology · Physics 2015-06-15 Mauricio Cataldo , Paola Meza

In the context of brane cosmology, we investigate exact solution of the gravitational field equations in the Randall-Sundrum model for an anisotropic brane with Bianchi V geometry, with a generalized Chaplygin gas, which plays the role of…

General Relativity and Quantum Cosmology · Physics 2012-09-14 Özgür Sevinc , Gülçin , Uluyazi

We have discussed here a higher dimensional cosmological model and explained the recent acceleration with a Chaplygin type of gas. Dimensional reduction of extra space is possible in this case. Our solutions are general in nature because…

General Relativity and Quantum Cosmology · Physics 2021-07-27 D. Panigrahi , B. C. Paul , S. Chatterjee

Singularities in the dark energy late universe are discussed, under the assumption that the Lagrangian contains the Einstein term R plus a modified gravity term R^\alpha, where \alpha is a constant. The 4D fluid is taken to be viscous and…

General Relativity and Quantum Cosmology · Physics 2008-12-18 Iver Brevik

We consider a universe filled by a modified generalized Chaplygin gas together with a pressureless dark matter component. We get a thermodynamical interpretation for the modified generalized Chaplygin gas confined to the apparent horizon of…

General Relativity and Quantum Cosmology · Physics 2016-05-18 H. Ebadi , H. Moradpour

Both dark energy models and modified gravity theories could lead to cosmological evolutions different from either the recollapse into a Big Crunch or exponential de Sitter expansion. The newly arising singularities may represent true…

General Relativity and Quantum Cosmology · Physics 2015-06-15 László Á. Gergely , Zoltán Keresztes , Alexander Yu. Kamenshchik

In this work we shall investigate the singularity structure of the phase space corresponding to an exponential quintessence dark energy model recently related to swampland models. The dynamical system corresponding to the cosmological…

General Relativity and Quantum Cosmology · Physics 2019-05-03 S. D. Odintsov , V. K. Oikonomou

The familiar Bang/Crunch singularities of classical cosmology have recently been augmented by new varieties: rips, sudden singularities, and so on. These tend to be associated with final states. Here we consider an alternative possibility…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Brett McInnes

We review recent work on the existence and nature of cosmological singularities that can be formed during the evolution of generic as well as specific cosmological spacetimes in general relativity. We first discuss necessary and sufficient…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Spiros Cotsakis

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

We consider a new approach for gravity theory coupled to Chaplygin matter in which the {\it{relativistic}} formulation of the latter is of crucial importance. We obtain a novel form of matter with dust like density $(\sim (volume)^{-1})$…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Rabin Banerjee , Subir Ghosh

We investigate de Sitter solutions in non-local gravity as well as in non-local gravity with Lagrange constraint multiplier. We examine a condition to avoid a ghost and discuss a screening scenario for a cosmological constant in de Sitter…

High Energy Physics - Theory · Physics 2015-05-27 Kazuharu Bamba , Shin'ichi Nojiri , Sergei D. Odintsov , Misao Sasaki

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

We review some of the well-known features of quantum cosmology, such as the factor ordering problem, the wave function and the density matrix, for a dark energy dominated universe, where analytical solutions can be obtained. For the…

General Relativity and Quantum Cosmology · Physics 2009-09-29 P. F. Gonzalez-Diaz , S. Robles-Perez

A brane scenario is envisaged in which the $m$-dimensional bulk is endowed with a Gauss-Bonnet term and localization of matter on the brane is achieved by means of a confining potential. The resulting Friedmann equations on the brane are…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. Heydari-Fard , H. R. Sepangi

We propose the Gauss-Bonnet dark energy model inspired by string/M-theory where standard gravity with scalar contains additional scalar-dependent coupling with Gauss-Bonnet invariant. It is demonstrated that effective phantom (or…

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

A cosmology with the growing cosmological term is considered. If there is no exchange of energy between vacuum and matter components, the requirement of general covariance implies the time dependence of the gravitational constant $G$.…

Astrophysics · Physics 2014-10-13 Hrvoje Stefancic