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Related papers: Cosmic acceleration with bulk viscosity in modifie…

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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

We use the hybrid model of bulk viscosity and generalized chaplygin gas (GCG), named the viscous generalized chaplygin gas (VGCG) model, which is thought to be an alternate dark fluid of the universe. We explore the dynamics of the VGCG…

General Relativity and Quantum Cosmology · Physics 2023-03-13 Gaurav N. Gadbail , Simran Arora , P. K. Sahoo

We study the evolution of a flat Friedmann-Robertson- Walker Universe, filled with a bulk viscous cosmological fluid, in the presence of variable gravitational and cosmological constants. The dimensional analysis of the model suggest a…

General Relativity and Quantum Cosmology · Physics 2009-09-25 J. A. Belinchon , T. Harko , M. K. Mak

In modern cosmology, the curiosity of ultimately understanding the nature of the dark energy controlling the recent acceleration of the Universe motivates us to explore its properties by using some novel approaches. In this work, to explore…

General Relativity and Quantum Cosmology · Physics 2023-12-19 Sanjay Mandal , Sneha Pradhan , P. K. Sahoo , Tiberiu Harko

In this paper, we investigate the existence of bulk viscous FLRW cosmological models in a recently proposed extended symmetric teleparallel gravity or $f\left( Q,T\right) $ gravity in which $Q$ is the non-metricity and $T$ is the trace of…

General Relativity and Quantum Cosmology · Physics 2022-12-01 M. Koussour , S. H. Shekh , M. Bennai , T. Ouali

We construct cosmological model in nonmetricity scalar functional gravitational Lagrangian $f(Q)$ which describes the dynamical evolution of the late accelerating universe. Cosmological models are constructed considering different…

General Relativity and Quantum Cosmology · Physics 2025-04-23 Bikash Chandra Roy , Aroonkumar Beesham , Bikash Chandra Paul

Inspired by an exponential $f(R)$ gravity model studied in the literature, in this work we introduce a new and viable $f(Q)$ gravity model, which can be represented as a perturbation of $\Lambda$CDM. Typically, within the realm of $f(Q)$…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-31 A. Oliveros , Mario A. Acero

In this manuscript, we studied the accelerated expansion history of the universe and the formations of large-scale structures using $f(Q)$ gravity model. The expansion rate of the universe within distance modulus and redshift has been…

General Relativity and Quantum Cosmology · Physics 2022-06-07 Shambel Sahlu , Endalkachew Tsegaye

The article communicates an alternative route to suffice the late-time acceleration considering a bulk viscous fluid with viscosity coefficient $\zeta =\zeta _{0}+ \zeta _{1} H + \zeta _{2} H^{2}$, where $\zeta _{0}, \zeta _{1}, \zeta _{2}$…

General Relativity and Quantum Cosmology · Physics 2020-07-20 Simran Arora , Snehasish Bhattacharjee , P. K. Sahoo

We study the bulk viscosity taking dust matter in the generalized teleparallel gravity. We consider different dark energy models in this scenario along with a time dependent viscous model to construct the viscous equation of state parameter…

General Relativity and Quantum Cosmology · Physics 2015-06-19 M. Sharif , Shamaila Rani

We consider a Friedmann model of the universe with bulk viscous matter and radiation as the cosmic components. We study the asymptotic properties in the equivalent phase space by considering the three cases for the bulk viscous coefficient…

General Relativity and Quantum Cosmology · Physics 2019-05-13 Athira Sasidharan , Titus K Mathew

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

In this paper, we have studied the late-time accelerating expansion of the Universe using the matter-geometry coupled $ f(Q, T) $ gravity model, where $ Q $ is the non-metricity scalar and $ T $ represents the trace of the energy-momentum…

General Relativity and Quantum Cosmology · Physics 2025-03-03 Shambel Sahlu , Bhupendra Kumar Shukla , Rishi Kumar Tiwari , Değer Sofuoğlu , Alnadhief H. A. Alfedeel

This paper is devoted to study the accelerated expansion of the universe by exploring the Brans-Dicke parameter in different eras. For this purpose, we take FRW universe model with viscous fluid (without potential) and Bianchi type I…

General Relativity and Quantum Cosmology · Physics 2015-06-15 M. Sharif , Saira Waheed

The objective of the present work is to study a cosmological model for a spatially flat Universe whose constituents are a dark energy field and a matter field which includes baryons and dark matter. The constituents are supposed to be in…

General Relativity and Quantum Cosmology · Physics 2013-09-13 Gilberto M. Kremer , Octavio A. S. Sobreiro

The cosmological observations suggest that the presently accelerating universe should be filled by an exotic form of matter, violating the strong energy condition, of unknown nature and origin. We propose the viscous dark matter of a source…

General Relativity and Quantum Cosmology · Physics 2020-08-05 Marek Szydlowski , Adam Krawiec

The dynamical aspect of accelerating cosmological model has been studied in this paper in the context of modified symmetric teleparallel gravity, the $f(Q)$ gravity. Initially, we have derived the dynamical parameters for two well known…

General Relativity and Quantum Cosmology · Physics 2023-07-18 S. A. Narawade , Shashank P. Singh , B. Mishra

The study conducted in this research paper utilizes the $f(Q,T)$ gravity, where $Q$ represents non-metricity and $T$ represents the trace of the energy-momentum tensor, to investigate the accelerated expansion of the universe. To complete…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-17 M. Koussour , N. Myrzakulov , J. Rayimbaev , A. Errehymy , Orhan Donmez

The primary aim of this work is to explore feasible bouncing cosmological solutions in the framework of $f(\mathcal{Q}, \mathcal{C})$ gravity, where $\mathcal{Q}$ denotes non-metricity and $\mathcal{C}$ indicates the boundary term. To…

General Relativity and Quantum Cosmology · Physics 2025-08-12 M. Sharif , M. Zeeshan Gul , Ahmad Nawaz

In this paper, the dynamical behavior of the anisotropic universe has been investigated in $f(R,T)$ theory of gravity. The functional $f(R,T)$ has been rescaled in the form $f(R,T)=\mu R+\mu T$, where $R$ is the Ricci scalar and $T$ is the…

General Physics · Physics 2018-01-08 B. Mishra , S Tarai , S. K. J. Pacif