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Related papers: Bulk viscosity, interaction and the viability of p…

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We investigate the phase space dynamics of a bulk viscosity model in the Eckart approach for a spatially flat Friedmann-Robertson-Walker universe. We have included two barotropic fluids and a dark energy component. One of the barotropic…

General Relativity and Quantum Cosmology · Physics 2014-10-29 Norman Cruz , Samuel Lepe , Yoelsy Leyva , Francisco Peña , Joel Saavedra

We study a cosmological model composed of a dark energy fluid interacting with a viscous matter fluid in a spatially flat Universe. The matter component represents the baryon and dark matter and it is taken into account, through a bulk…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Arturo Avelino

If nonrelativistic dark matter and radiation are allowed to interact, reaching an approximate thermal equilibrium, this interaction induces a bulk viscous pressure changing the effective one-fluid description of the universe dynamics,…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-18 Hermano Velten , William Iania

It is performed a detailed dynamical analysis for a bulk viscosity model in the full Israel-Stewart formalism for a spatially flat Friedmann-Robertson-Walker Universe. In our study we have considered the total cosmic fluid constituted by…

General Relativity and Quantum Cosmology · Physics 2017-08-02 Samuel Lepe , Giovanni Otalora , Joel Saavedra

In this work, we present a phase space analysis of a spatially flat Friedmann $-$Robertson$-$Walker (FRW) model in which the dark matter fluid is modeled as an imperfect fluid having bulk viscosity. The bulk viscosity is governed by the…

General Relativity and Quantum Cosmology · Physics 2019-01-23 Yoelsy Leyva

We investigate cosmological models with two interacting fluids: dark energy and dark matter in flat Friedmann-Robertson-Walker universe. The interaction between dark energy and dark matter is described in terms of the parameters present in…

General Relativity and Quantum Cosmology · Physics 2015-02-23 I. Brevik , V. V. Obukhov , A. V. Timoshkin

We investigate a spatially flat Friedmann-Robertson-Walker (FRW) scenario with two interacting components, dark matter and variable vacuum energy (VVE) densities, plus two decoupled components, one is a baryon term while the other behaves…

General Relativity and Quantum Cosmology · Physics 2015-08-21 Iván E. Sánchez G

The universe content is considered as a non-perfect fluid with bulk viscosity and can be described by a general equation of state (endowed some deviation from the conventionally assumed cosmic perfect fluid model). An explicitly bulk…

Astrophysics · Physics 2009-10-16 X H Meng , X Dou

Non-gravitational interaction between dark matter and dark energy has been considered in a spatially flat Friedmann-Lema\^{i}tre-Robertson-Walker (FLRW) universe. The interaction rate is assumed to be linear in the energy densities of dark…

General Relativity and Quantum Cosmology · Physics 2020-07-07 Supriya Pan , Jaume de Haro , Weiqiang Yang , Jaume Amorós

We study the evolution of the dark energy parameter within the scope of a spatially non-flat and isotropic Friedmann-Robertson-Walker (FRW) model filled with barotropic fluid and bulk viscous stresses. We have obtained cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Hassan Amirhashchi , Anirudh Pradhan , Hishamuddin Zainuddin

In the context of dark energy solutions, we consider a Friedmann-Robertson-Walker spacetime filled with a non-interacting mixture of dust and a viscous fluid, whose bulk viscosity is governed by the nonlinear model proposed in [15]. Through…

General Relativity and Quantum Cosmology · Physics 2015-06-19 G. Acquaviva , A. Beesham

Considering the condition on conservation of energy momentum tensor (EMT), we study late time cosmological solutions in the context of $f(R,T)=R+\alpha T^{n}$ gravity (where $\alpha$ and $n$ are constants) in a flat FLRW spacetime. The…

General Relativity and Quantum Cosmology · Physics 2024-03-06 Hamid Shabani , Norman Cruz , Amir Hadi Ziaie

In this paper we investigate the evolution of the viscous dark energy (DE) interacting with the dark matter (DM) in the Einstein cosmology model. Using the linearizing theory of the dynamical system, we find, in our model, there exists a…

General Relativity and Quantum Cosmology · Physics 2009-09-05 Juhua Chen , Yongjiu Wang

We revise the conditions for the physical viability of a cosmological model in which dark matter has bulk viscosity and also interacts with dark energy. We have also included radiation and baryonic matter components; all matter components…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Arturo Avelino , Yoelsy Leyva , L. Arturo Urena-Lopez

The phantom dark energy remarkably boosts our prehension of the accelerating Universe. Various models are widely discussed in the phantom Universe without bulk viscosity. From the hydrodynamics' point of view, it is natural to introduce the…

General Relativity and Quantum Cosmology · Physics 2020-06-11 Ji-Yao Wang , Chao-Jun Feng , Xiang-Hua Zhai , Xin-Zhou Li

Extensions to a $\Lambda$DM model have been explored to face current tensions that occur within its framework, which encompasses broadening the nature of the dark matter (DM) component to include warmness and a non-perfect fluid…

General Relativity and Quantum Cosmology · Physics 2022-09-27 Norman Cruz , Esteban González , Jose Jovel

We investigate the cosmological implications of a phantom dark energy model with bulk viscosity. We explore this model as a possible way to resolve the big rip singularity problem that plagues the phantom models. We use the latest type Ia…

General Relativity and Quantum Cosmology · Physics 2023-12-21 Jing Yang , Rui-Hui Lin , Chao-Jun Feng , Xiang-Hua Zhai

In this work we present the cosmological dynamics of interacting dark energy models in the framework of particle creation mechanism. The particle creation mechanism presented here describes the true non equilibrium thermodynamics of the…

General Relativity and Quantum Cosmology · Physics 2017-06-07 Sujay Kr. Biswas , Wompherdeiki Khyllep , Jibitesh Dutta , Subenoy Chakraborty

Singularities in the dark energy universe are discussed, assuming that there is a bulk viscosity in the cosmic fluid. In particular, it is shown how the physically natural assumption of letting the bulk viscosity be proportional to the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 I. Brevik , O. Gorbunova

In order to study if the bulk viscosity may induce a big rip singularity on the flat FRW cosmologies, we investigate dissipative processes in the universe within the framework of the standard Eckart theory of relativistic irreversible…

High Energy Physics - Theory · Physics 2008-11-26 Mauricio Cataldo , Norman Cruz , Samuel Lepe
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