English
Related papers

Related papers: Viscous Dark Energy in $f(T)$ Gravity

200 papers

Bulk viscosity, which characterizes the irreversible dissipative resistance of a fluid to volume changes, has been proposed as a potential mechanism for explaining both early- and late-time accelerated expansion of the Universe. In this…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-18 P. P. Avelino , A. R. Gomes , D. A. Tamayo

In this study, we investigate the role of bulk viscosity in $f(Q,T)$ gravity in explaining late-time cosmic acceleration. This model, an extension of symmetric teleparallel gravity, introduces viscosity into cosmic matter dynamics for a…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-14 M. Koussour , Abdelghani Errehymy , O. Donmez , K. Myrzakulov , M. A. Khan , B. Çil , E. Güdekli

In this article, we attempt to describe cosmic late-time acceleration of the universe in the framework of $f(R,L_m)$ gravity by using an effective equation of state when the account is taken of bulk viscosity. We presume a non-linear…

General Relativity and Quantum Cosmology · Physics 2023-03-31 Lakhan V. Jaybhaye , Raja Solanki , Sanjay Mandal , Pradyumn Kumar Sahoo

In this paper we have investigated the general form of viscous and non-viscous dark energy equation of state (EoS) parameter in the scope of anisotropic Bianchi type I space-time. We show that the presence of bulk viscosity causes…

General Relativity and Quantum Cosmology · Physics 2014-03-20 Hassan Amirhashchi , Anirudh Pradhan

Bulk viscosity is the only viscous influence that can change the background dynamics in a homogeneous and isotropic universe. In the present work, we analyze the bulk viscous cosmological model with the bulk viscosity coefficient of the…

General Relativity and Quantum Cosmology · Physics 2021-12-13 Gaurav Gadbail , Simran Arora , P. K. Sahoo

In this paper, we study the cosmological evolution of a viscous dark energy model within the framework of $f(Q, C)$ gravity, utilizing a two-fluid approach. The model incorporates non-metricity and boundary contributions to the total…

General Relativity and Quantum Cosmology · Physics 2025-10-15 N. Myrzakulov , Anirudh Pradhan , S. H. Shekh

We describe the accelerated expansion of the late-time universe using a generalized equation of state (EoS) when account is taken of bulk viscosity. We assume a homogeneous and isotropic Friedmann-Robertson-Walker spacetime. Solutions of…

General Relativity and Quantum Cosmology · Physics 2019-08-05 I. Brevik , A. N. Makarenko , A. V. Timoshkin

The unified dark energy and dark matter model within the framework of a model of a continuous medium with bulk viscosity (dark fluid) is considered. It is supposed that the bulk viscosity coefficient is an arbitrary function of the Hubble…

Astrophysics · Physics 2009-06-23 V. Folomeev , V. Gurovich

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

We study the late-time cosmological dynamics of a spatially flat FLRW universe in the framework of $f(Q)$ gravity, where $Q$ denotes the nonmetricity scalar. The matter sector is modeled as a bulk viscous fluid with a free equation-of-state…

General Relativity and Quantum Cosmology · Physics 2026-02-20 Simran Arora , Sai Swagat Mishra , P. K. Sahoo

We investigate the late-time cosmic acceleration within the framework of viscous $f(T,L_m)$ gravity, where the gravitational action depends on both the torsion scalar $T$ and the matter Lagrangian $L_m$. In this context, the Universe is…

General Physics · Physics 2026-03-24 M. Koussour , Alnadhief H. A. Alfedeel , S. Muminov , J. Rayimbaev

We present a discussion of the effects induced by bulk viscosity either on the very early Universe stability and on the dynamics associated to the extreme gravitational collapse of a gas cloud. In both cases the viscosity coefficient is…

General Relativity and Quantum Cosmology · Physics 2009-03-24 Nakia Carlevaro , Giovanni Montani

The whole article deals with the analysis of the cosmic model of Ruban's space-time in the context of a bulk viscosity impact in the form of Ricci dark energy within the framework Brans-Dicke theory (Brans and Dicke, Phys. Rev. 124, 925…

General Relativity and Quantum Cosmology · Physics 2023-11-03 M. Vijayasanthi , T. Chinnappalanaidu , S. Srivani Madhu

Evolution of the bulk viscous matter dominated universe has been analysed using the full causal, Israel-Stewart theory for the evolution of bulk viscous pressure in the context of recent acceleration of the universe. The form of bulk…

General Relativity and Quantum Cosmology · Physics 2018-04-23 Jerin Mohan N D , Athira Sasidharan , Titus K Mathew

We propose an approach considering the nonextensive effects in the context of the Verlinde theory in order to address an extended cosmological model in the context of viscous dark energy. Specifically, this model leads to a tiny…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-24 W. J. C. da Silva , R. Silva

Various studies have shown that the late acceleration of the universe can be caused by the bulk viscosity associated with dark matter. But recently, it was indicated that a cosmological constant is essential for maintaining Near Equilibrium…

General Relativity and Quantum Cosmology · Physics 2023-11-10 Vishnu A Pai , Titus K Mathew

In this paper, we introduce bulk viscosity in the formalism of modified gravity theory in which the gravitational action contains a general function $f(R,T)$, where $R$ and $T$ denote the curvature scalar and the trace of the…

General Relativity and Quantum Cosmology · Physics 2015-03-02 C. P. Singh , Pankaj Kumar

Recent measurements suggest our universe has a substantial dark energy component, which is usually interpreted in terms of a cosmological constant. Here we examine how much the form of this dark energy can be modified while still retaining…

High Energy Physics - Phenomenology · Physics 2009-11-07 Duane A. Dicus , Wayne W. Repko

In this paper, we study the $F(R, G)$ gravity model with an interacting model by flat-FRW metric in a viscous fluid. We consider that the universe dominates with components of dark matter and dark energy. This means that the dark matter…

General Relativity and Quantum Cosmology · Physics 2023-03-22 E. Mahichi , Alireza Amani , M. A. Ramzanpour

We propose a scenario in which the dark components of the Universe are manifestations of a single bulk viscous fluid. Using dynamical system methods, a qualitative study of the homogeneous, isotropic background scenario is performed in…

Astrophysics · Physics 2008-12-18 R. Colistete , J. C. Fabris , J. Tossa , W. Zimdahl