English
Related papers

Related papers: Bulk Viscous Cosmology

200 papers

In this work we explore the thermodynamic aspects of dark energy for late future time universe in two different scenarios: as a perfect fluid with constant and variable equation of state parameter; and as dissipative fluid described by a…

General Relativity and Quantum Cosmology · Physics 2022-03-03 David Tamayo

We derive an extended expression for the relaxation time of a barotropic Israel-Stewart (IS) fluid using the non-linear causality constraint, and propose a new formulation for modeling causal viscous dissipation in barotropic fluids. With…

General Relativity and Quantum Cosmology · Physics 2025-12-19 Vishnu A Pai , Titus K Mathew

The dynamical system behaviour and thermal evolution of a homogeneous and isotropic dissipative universe are analyzed. The dissipation is driven by the bulk viscosity $\xi = \alpha \rho^s $ and the evolution of bulk viscous pressure is…

General Relativity and Quantum Cosmology · Physics 2020-03-11 Jerin Mohan N D , Krishna P B , Athira Sasidharan , Titus K Mathew

Exact solutions for a model with variable $G$, $\Lambda$ and bulk viscosity are obtained. Inflationary solutions with constant (de Sitter-type) and variable energy density are found. An expanding anisotropic universe is found to isotropize…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Arbab I. Arbab

Combining the equivalence between cosmological particle creation and an effective viscous fluid pressure with the fact that the latter represents a dynamical degree of freedom within the second-order Israel-Stewart theory for imperfect…

Astrophysics · Physics 2009-10-31 Winfried Zimdahl

We investigate the thermodynamics of a dark energy bulk viscosity model as a cosmic fluid. In this regard, the two theories of Eckart and Israel-Stewart (IS) are the basis of our work. Therefore, we first investigate the thermodynamics of…

General Relativity and Quantum Cosmology · Physics 2024-09-10 S. Davood Sadatian , A. Saburi

The incorporation of bulk viscosity process to General Relativity leads to the appearance of nonsingular backgrounds that, at early and late times, depict an accelerated universe. These backgrounds could be analytically calculated and…

General Relativity and Quantum Cosmology · Physics 2017-12-20 Jaume Haro , Supriya Pan

Hydro-kinetic theory of thermal fluctuations is applied to a non-conformal relativistic fluid. Solving the hydro-kinetic equations for an isotropically expanding background we find that hydrodynamic fluctuations give ultraviolet divergent…

Nuclear Theory · Physics 2018-08-21 Yukinao Akamatsu , Aleksas Mazeliauskas , Derek Teaney

The Misner and Sharp approach to the study of gravitational collapse is extended to the viscous dissipative case in, both, the streaming out and the diffusion approximations. The dynamical equation is then coupled to causal transport…

General Relativity and Quantum Cosmology · Physics 2009-03-24 L. Herrera , A. Di Prisco , E. Fuenmayor , O. Troconis

The exact general solution to the Einstein equations in a homogeneous Universe with a full causal viscous fluid source for the bulk viscosity index $m=1/2$ is found. We have investigated the asymptotic stability of Friedmann and de Sitter…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Luis P. Chimento , Alejandro S. Jakubi

We test the physical relevance of the full and the truncated versions of the Israel-Stewart theory of irreversible thermodynamics in a cosmological setting. Using a dynamical systems method, we determine the asymptotic future of plane…

General Relativity and Quantum Cosmology · Physics 2016-09-30 Dmitry Shogin , Per Amund Amundsen

In this work we explore a new cosmological solution for an universe filled with one dissipative fluid, described by a barotropic EoS $p = \omega \rho$, in the framework of the full Israel-Stewart theory. The form of the bulk viscosity has…

General Relativity and Quantum Cosmology · Physics 2017-12-20 Miguel Cruz , Norman Cruz , Samuel Lepe

In this paper, we have presented bulk viscous cosmological model of the universe in the modified gravity theory in which the Lagragian of the gravitational action contains a general function $f(R, T) $, where $R$ and $T$ denote the…

General Relativity and Quantum Cosmology · Physics 2019-07-05 Partha Sarathi Debnath

This article extends the single-fluid relativistic irreversible thermodynamics theory of {\it M{\"u}ller}, {\it Israel} and {\it Stewart} (hereafter the {MIS} theory) to a multi-fluid system with inherent species interactions. This is…

General Relativity and Quantum Cosmology · Physics 2020-04-23 Bob Osano

We study evolution of a flat Friedmann-Robertson Walker universe filled with a bulk viscous cosmological fluid in a higher derivative theory of gravity in the presence of time varying gravitational and cosmological constant. Cosmological…

General Relativity and Quantum Cosmology · Physics 2015-03-13 B. C. Paul , P. S. Debnath

The general solution of the gravitational field equations for a full causal bulk viscous stiff cosmological fluid, with bulk viscosity coefficient proportional to the energy density to the power 1/4, is obtained in the flat…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. K. Mak , T. Harko

We here investigate bulk-viscosity driven quasi de-Sitter inflation, that is, the period of accelerated expansion in the early universe during which $-\dot{H}\ll H^2$, with $H(t)$ being the Hubble expansion rate. We do so in the framework…

General Relativity and Quantum Cosmology · Physics 2024-02-21 Sayantani Lahiri , Luciano Rezzolla

We examine the cosmological consequences of an alternative to the standard expression for bulk viscosity, one which was proposed to avoid the propagation of superluminal signals without the necessity of extending the space of variables of…

General Relativity and Quantum Cosmology · Physics 2016-04-08 Marcelo M. Disconzi , Thomas W. Kephart , Robert J. Scherrer

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

General Relativity and Quantum Cosmology · Physics 2008-11-26 T. Harko , M. K. Mak

The first-order general relativistic theory of a generic dissipative (heat-conducting, viscous, particle-creating) fluid is rediscussed from a unified covariant frame-independent point of view. By generalizing some previous works in the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 R. Silva , J. A. S. Lima , M. O. Calvão