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Related papers: Bulk Viscous Cosmology

200 papers

It is shown that two reacting cosmological fluids, each of them perfect on its own, which exchange energy and momentum without preserving particle numbers, give rise to an entropy producing `reactive' bulk stress of the system as a whole,…

Astrophysics · Physics 2015-06-24 Winfried Zimdahl

We discuss a cosmology in which cold dark-matter particles decay into relativistic particles. We argue that such decays could lead naturally to a bulk viscosity in the cosmic fluid. For decay lifetimes comparable to the present hubble age,…

Astrophysics · Physics 2008-11-26 James R. Wilson , Grant J. Mathews , George M. Fuller

We present a formulation of special relativistic, dissipative hydrodynamics (SRDHD) derived from the well-established M\"uller- Israel-Stewart (MIS) formalism using an expansion in deviations from ideal behaviour. By re-summing the…

General Relativity and Quantum Cosmology · Physics 2024-05-16 Marcus J. Hatton , Ian Hawke

The holographic principle in a radiation dominated universe is extended to incorporate the case of a bulk-viscous cosmic fluid. This corresponds to a nonconformally invariant theory. Generalization of the Cardy-Verlinde entropy formula to…

General Relativity and Quantum Cosmology · Physics 2009-01-14 Iver Brevik

We consider a cosmological model dominated by stiff fluid with a constant bulk viscosity. We classify all the possible cases of the universe predicted by the model and analyzing the scale factor, density as well as the curvature scalar. We…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Titus K Mathew , Aswathy M B , Manoj M

We construct a relativistic model for bulk viscosity and heat conduction in a superfluid. Building on the principles of Unified Extended Irreversible Thermodynamics, the model is derived from Carter's multifluid approach for a theory with 3…

General Relativity and Quantum Cosmology · Physics 2022-02-23 Lorenzo Gavassino , Marco Antonelli , Brynmor Haskell

In a spatially flat Friedmann-Lema\^{i}tre-Robertson-Walker universe, we investigate a unified cosmic fluid scenario endowed with bulk viscosity in which the coefficient of the bulk viscosity has a power law evolution. The power law in the…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-20 Weiqiang Yang , Supriya Pan , Eleonora Di Valentino , Andronikos Paliathanasis , Jianbo Lu

By using the thermodynamic theory of irreversible processes and Einstein general relativity, a cosmological model is proposed where the early universe is considered as a mixture of a scalar field with a matter field. The scalar field refers…

General Relativity and Quantum Cosmology · Physics 2009-11-07 G. M. Kremer , F. P. Devecchi

The formulation of a universal theory for bulk viscosity and heat conduction represents a theoretical challenge for our understanding of relativistic fluid dynamics. Recently, it has been shown that the multifluid variational approach…

General Relativity and Quantum Cosmology · Physics 2020-10-15 Lorenzo Gavassino , Marco Antonelli , Brynmor Haskell

The stability of the 1+1 dimensional solution of Israel-Stewart theory is investigated. Firstly, the evolution of the temperature and the ratio of the bulk pressure over the equilibrium pressure of the background is explored. Then the…

Nuclear Theory · Physics 2014-04-29 J. W. Li , Y. G. Ma , G. L. Ma

In this paper we have discussed the modified gravity and scalar field DE model specifically DBI essence model with the analysis of thermodynamics during cosmological evolution. We have used the modified gravity with the form…

General Physics · Physics 2022-06-02 Shouvik Sadhukhan , Alokananda Kar , Surajit Chattopadhyay

A spatially homogeneous and locally rotationally symmetric Bianchi type-II cosmological model under the influence of both shear and bulk viscosity has been studied. Exact solutions are obtained with a barotropic equation of state between…

General Relativity and Quantum Cosmology · Physics 2021-05-11 A. Banerjee , S. B. Duttachoudhury , Abhik Kumar Sanyal

The aim of this paper is to investigate the dynamical aspects of charged viscous cylindrical source by using Misner approach. To this end, we have considered the more general charged dissipative fluid enclosed by the cylindrical symmetric…

General Relativity and Quantum Cosmology · Physics 2018-01-24 S. M. Shah , G. Abbas

We analyze the dynamics of models of warm inflation with general dissipative effects. We consider phenomenological terms both for the inflaton decay rate and for viscous effects within matter. We provide a classification of the asymptotic…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Jose P. Mimoso , Ana Nunes , Diego Pavon

In this paper we present two concrete models of non-perfect fluid with bulk viscosity to interpret the observed cosmic accelerating expansion phenomena, avoiding the introduction of exotic dark energy. The first model we inspect has a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Xin-he Meng , Zhi-yuan Ma

This article explores the impact of bulk viscosity on understanding the universe's accelerated expansion within the context of modified $f(T,\mathcal{T})$ gravity, which is an extension of the $f(T)$ gravitational theory, allowing a broad…

General Relativity and Quantum Cosmology · Physics 2024-07-29 Raja Solanki , Aaqid Bhat , P. K. Sahoo

We propose to describe the acceleration of the universe by introducing a model of two coupled fluids. We focus on the accelerated expansion at the early stages. The inflationary expansion is described in terms of a van der Waals equation of…

General Relativity and Quantum Cosmology · Physics 2018-05-28 I. Brevik , V. V. Obukhov , A. V. Timoshkin

Bulk viscous cosmological models is presented in the teleparallel ($F(T)$, where $T$ denotes torsion) gravity. In the teleparallel gravity, the Lagrangian of the gravitational action contains a general function $F(T)= T+ f(T)=(1+ \gamma)…

General Relativity and Quantum Cosmology · Physics 2025-07-22 Partha Sarathi Debnath , Chanchal Mondal , B. C. Paul

We present dynamical description of gravitational collapse in view of Misner and Sharp's formalism. Matter under consideration is a complicated fluid consistent with plane symmetry which we assume to undergo dissipation in the form of heat…

General Relativity and Quantum Cosmology · Physics 2014-11-20 M. Sharif , Zakia Rehmat

We discuss influences of bulk viscosity on the Early Universe, which is modeled by Friedmann-Robertson-Walker metric and Einstein field equations. We assume that the matter filling the isotropic and homogeneous background is relativistic…

General Relativity and Quantum Cosmology · Physics 2009-12-02 A. Tawfik , H. Mansour , M. Wahba
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