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We discuss the fate of classical type IV singularities in quantum cosmology. The framework is Wheeler-DeWitt quantization applied to homogeneous and isotropic universes with a perfect fluid described by a generalized Chaplygin gas. Such a…

General Relativity and Quantum Cosmology · Physics 2014-03-12 Mariam Bouhmadi-Lopez , Claus Kiefer , Manuel Kraemer

Flat FRW perfect fluid cosmologies can be reproduced as particular solutions of suitable field theoretical models. Here we investigate the stability of perfect fluid model trajectories with respect to sets of trajectories of the…

The development of dark energy models has stimulated interest to cosmological singularities, which differ from the traditional Big Bang and Big Crunch singularities. We review a broad class of phenomena connected with soft cosmological…

General Relativity and Quantum Cosmology · Physics 2013-08-27 A. Yu. Kamenshchik

In this paper, we consider the Universe at the late stage of its evolution and deep inside the cell of uniformity. At these scales, the Universe is filled with inhomogeneously distributed discrete structures (galaxies, groups and clusters…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Alvina Burgazli , Maxim Eingorn , Alexander Zhuk

A flat FLRW cosmological model with perfect fluid comprising of variable Chaplygin gas has been studied in context of f(R; T) gravity with particle creation. The considered scale factors describe the accelerated expansion of universe due to…

General Relativity and Quantum Cosmology · Physics 2020-02-12 N. Hulke , G. P. Singh , Binaya K. Bishi , A. Singh

Cosmological models with time dependent $\Lambda$ (read as $\Lambda (t)$) have been investigated widely in the literature. Models that solve background dynamics analytically, are of special interest. Additionally, the allowance of past or…

General Relativity and Quantum Cosmology · Physics 2018-01-08 Supriya Pan

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

We study the dynamics near finite-time singularities of flat isotropic universes filled with two interacting but otherwise arbitrary perfect fluids. The overall dynamical picture reveals a variety of asymptotic solutions valid locally…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Spiros Cotsakis , Georgia Kittou

We present a Friedmann-Robertson-Walker quantum cosmological model in the presence of Chaplygin gas and perfect fluid for early and late time epoches. In this work, we consider perfect fluid as an effective potential and apply Schutz's…

General Relativity and Quantum Cosmology · Physics 2008-11-26 P. Pedram , S. Jalalzadeh

In this paper we consider the flat FRW cosmology with a scalar field coupled with the metric along with generalized Chaplygin gas and perfect fluid comprising the matter sector. We use the Schutz's formalism to deal with the generalized…

General Relativity and Quantum Cosmology · Physics 2018-02-14 Saumya Ghosh , Sunandan Gangopadhyay , Prasanta K. Panigrahi

Osgood functions in the source term are used to produce results for non-existence of local solutions into the framework of non-Gaussian diffusion equations. The critical exponent for non-existence of local solutions is found to depend on…

Analysis of PDEs · Mathematics 2024-05-24 Soveny Solís , Vicente Vergara

We extend our previous study on the effects of an information-theoretically motivated nonlinear correction to the Wheeler-deWitt equation in the minisuperspace scheme for FRW universes. Firstly we show that even when the geometry is…

General Relativity and Quantum Cosmology · Physics 2009-05-01 Le-Huy Nguyen , Rajesh R. Parwani

The Modified Chaplygin Gas (MCG) model is revisited to examine its ability to describe the full cosmic evolution within a single framework. Because the field equations are highly nonlinear, no closed analytical solution for the scale factor…

General Relativity and Quantum Cosmology · Physics 2025-12-23 D. Panigrahi , S. Chatterjee , B. C. Paul

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

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

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 2024-08-02 Oem Trivedi , Maxim Khlopov

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

The paper establishes the result that solutions of the type described in the title of the article are only those that have been already presented in the literature. The procedure adopted in the paper is somewhat novel - while the usual…

General Relativity and Quantum Cosmology · Physics 2009-11-07 A. K. Raychaudhuri

In this talk we would like to review recent results on non-singular cosmological models. It has been recently shown that among stiff perfect fluid inhomogeneous spacetimes the absence of singularities is more common than it was expected in…

General Relativity and Quantum Cosmology · Physics 2009-04-29 L. Fernández-Jambrina , L. M. González-Romero

We investigate a cosmological model whose energy content is described by a Chaplygin gas represented by a scalar field $\phi$ with an associated potential producing a big bang singularity such that for vanishing scale factor, $a\to 0$, one…

General Relativity and Quantum Cosmology · Physics 2010-01-29 Frank Steiner , Andreas Woehr
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