English
Related papers

Related papers: Full Causal Bulk Viscous Cosmological Models with …

200 papers

A new class of exact solutions of Einstein's field equations with a perfect fluid source, variable gravitational coupling $G$ and cosmological term $\Lambda$ for FRW spacetime is obtained by considering variable deceleration parameter…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Anirudh Pradhan , Ajay Kumar Singh , Saeed Otarod

Recent studies indicate that, near equilibrium condition could not be maintained for bulk viscous matter models during the accelerated expansion of the universe in the context of Einstein's gravity, without including the cosmological…

General Relativity and Quantum Cosmology · Physics 2023-03-28 Vishnu A Pai , Titus K Mathew

Assuming that the matter filling the background geometry in the Early Universe was a free gas and no phase transitions took place, we discuss the thermodynamics of this closed system using classical approaches. We found that essential…

General Relativity and Quantum Cosmology · Physics 2010-11-11 A. Tawfik

We study the classical flat full causal bulk viscous FRW cosmological model through the factorization method. The method shows that there exists a relationship between the viscosity parameter $s$ and the parameter $\gamma$ entering the…

General Relativity and Quantum Cosmology · Physics 2013-04-05 O. Cornejo-Pérez , J. A. Belinchón

We consider the dynamics of a viscous cosmological fluid in the generalized Randall-Sundrum model for an isotropic brane. To describe the dissipative effects we use the Israel-Hiscock-Stewart full causal thermodynamic theory. In the…

High Energy Physics - Theory · Physics 2008-11-26 Chiang-Mei Chen , T. Harko , M. K. Mak

Several isotropic, homogeneous cosmological models containing a self-interacting minimally coupled scalar field, a perfect fluid source and cosmological constant are solved. New exact, asymptotically stable solutions with an inflationary…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Luis P. Chimento , Alejandro S. Jakubi

Bulk viscosity has been intrinsically existing in the observational cosmos evolution with various effects for different cosmological evolution stages endowed with complicated cosmic media. Normally in the idealized "standard cosmology" the…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-22 Jiaxin Wang , Xinhe Meng

In this paper we present the equations of the evolution of the universe in $D$ spatial dimensions, as a generalization of the work of Lima \citep{lima}. We discuss the Friedmann-Robertson-Walker cosmological equations in $D$ spatial…

General Relativity and Quantum Cosmology · Physics 2012-07-09 R. F. L. Holanda , S. H. Pereira

The Einstein's field equations of Friedmann-Robertson-Walker universes filled with a dissipative fluid described by both the {\em truncated} and {\em non-truncated} causal transport equations are analyzed using techniques from dynamical…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Vicenç Mendez , Josep Triginer

The full causal M\"uller-Israel-Stewart (MIS) theory of dissipative processes in relativistic fluids is applied to a flat, homogeneous and isotropic universe with bulk viscosity. It is clarified in which sense the so called truncated…

Astrophysics · Physics 2008-11-26 Winfried Zimdahl

We study noncommutative classical Friedmann-Robertson-Walker cosmological models. The constant curvature of the spatial sections can be positive ($k=1$), negative ($k=-1$) or zero ($k=0$). The matter is represented by a perfect fluid with…

General Relativity and Quantum Cosmology · Physics 2017-01-06 G. Oliveira-Neto , A. R. Vaz

A complete analysis of the dynamics of the Hu-Sawicki modification to General Relativity is presented. In particular, the full phase-space is given for the case in which the model parameters are taken to be n=1, c1=1, and several stable de…

General Relativity and Quantum Cosmology · Physics 2015-11-03 Sulona Kandhai , Peter K. S. Dunsby

The Full (non--truncated) Israel--Stewart theory of bulk viscosity is applied to dissipative FRW spacetimes. Dimensionless variables and dimensionless equations of state are used to write the Einstein--thermodynamic equations as a plane…

General Relativity and Quantum Cosmology · Physics 2009-10-28 A. A. Coley , R. J. van den Hoogen , R. Maartens

A scalar-tensor bimetric gravity model of early universe cosmology is reviewed. The metric frame with a variable speed of light (VSL) and a constant speed of gravitational waves is used to describe a Friedmann-Robertson-Walker universe. The…

General Relativity and Quantum Cosmology · Physics 2009-11-10 J. W. Moffat

In this work, we present a method for numerically solving the Friedmann equations of modified $f(\mathcal{G})$ gravity in the presence of pressureless matter. This method enables us to predict the redshift behaviour of the Hubble expansion…

General Relativity and Quantum Cosmology · Physics 2024-11-08 Santosh V. Lohakare , Soumyadip Niyogi , B. Mishra

Bulk viscosity in cold dark matter is an appealing feature that introduces distinctive phenomenological effects in the cosmological setting as compared to the $\Lambda$CDM model. Under this view, we propose a general parametrization of the…

General Relativity and Quantum Cosmology · Physics 2023-08-24 Gabriel Gómez , Guillermo Palma , Ángel Rincón , Norman Cruz , Esteban González

The evolution of a flat, isotropic and homogeneous universe is studied. The background geometry in the early phases of the universe is conjectured to be filled with causal bulk viscous cosmological fluid and dark energy. The energy density…

General Relativity and Quantum Cosmology · Physics 2012-04-23 A. Tawfik

We have considered a cosmological model of the FRW universe with variable $G$ and $\Lambda$. The solutions have been obtained for flat model with particular form of cosmological constant. The cosmological parameters have also been obtained…

General Relativity and Quantum Cosmology · Physics 2011-03-31 Mubasher Jamil , Ujjal Debnath

We provide an analytical solution to the quantum dynamics of a flat Friedmann-Lema\^itre- Robertson-Walker model with a massless scalar field in the presence of a small and positive cosmological constant, in the context of Loop Quantum…

General Relativity and Quantum Cosmology · Physics 2020-02-06 Mercedes Martín-Benito , Rita B. Neves

In this work we discuss a general approach for the dissipative dark matter considering a nonextensive bulk viscosity and taking into account the role of generalized Friedmann equations. This generalized $\Lambda$CDM model encompasses a flat…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-19 W. J. C. da Silva , H. S. Gimenes , R. Silva