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Related papers: Constraining viscous fluid models in $f(Q)$ gravit…

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Gravitational and hydrodynamical perturbations are analysed in a relativistic plasma containing a mixture of interacting fluids characterized by a non-negligible bulk viscosity coefficient. The energy-momentum transfer between the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Massimo Giovannini

In this paper, we have analyzed the significance of bulk viscosity in an axially symmetric Bianchi type-I model to study the accelerated expansion of the universe. We have considered four bulk viscosity parameterizations for the…

General Relativity and Quantum Cosmology · Physics 2022-12-21 Archana Dixit , Anirudh Pradhan , Vinod Kumar Bhardwaj , A. Beesham

In this paper, we present a cosmological model within the framework of symmetric teleparallel gravity, focusing on $f(Q)$ gravity, where $Q$ represents the non-metricity scalar. Utilizing cosmological datasets, we derive an accelerating…

General Relativity and Quantum Cosmology · Physics 2024-08-09 S. A. Narawade , S. H. Shekh , B. Mishra , Wompherdeiki Khyllep , Jibitesh Dutta

Motivated by the fact that cosmological models based on $f(Q)$ gravity are very efficient in fitting observational datasets at both background and perturbation levels, we perform a combined dynamical system analysis of both background and…

General Relativity and Quantum Cosmology · Physics 2023-02-22 Wompherdeiki Khyllep , Jibitesh Dutta , Emmanuel N. Saridakis , Kuralay Yesmakhanova

In the present work, we study a cosmological model composed of a viscous dark matter interacting with decaying vacuum energy in a spatially flat Universe. In the first part, we find the analytical solution of different cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-27 Vinita Khatri , C. P. Singh , Milan Srivastava

In this paper, we reconstruct the $f(R)$ theory using the viscous $\omega$CDM scenario (V-$\omega$CDM) constrained by several differently astrophysical observations, including Type Ia supernovae (SNe Ia), observational Hubble parameter data…

General Relativity and Quantum Cosmology · Physics 2016-04-12 Deng Wang , Xin-He Meng

We study the effect of $f(R)$ gravity on the statistical properties of various large-scale structures which can be probed in weak gravitational lensing measurements. A set of ray-tracing simulations of gravitational lensing in $f(R)$…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-04 Yuichi Higuchi , Masato Shirasaki

This paper delves into the late-time accelerated expansion of the universe and the evolution of cosmic structures within the context of a specific \( f(R, L_m) \) gravity model, formulated as \( f(R, L_m) = \lambda R + \beta L_m^\alpha +…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-05 Shambel Sahlu , Alnadhief H. A. Alfedeel , Amare Abebe

This study combines theoretical advancements with observational limitations to investigate the cosmological implications of a bulk viscous modified Chaplygin gas (MCG) in a Friedmann--Robertson--Walker (FRW) in (3+1) dimensional spacetime…

General Relativity and Quantum Cosmology · Physics 2025-12-23 Mohit Thakre , Praveen Kumar Dhankar , Behnam Pourhassan , Safiqul Islam

In this study, we explore the cosmological evolution of the Universe in the framework of covariant $f(Q)$ gravity, with a coupling function that evolves dynamically in proportion to the Hubble parameter. Two specific forms of the function…

General Relativity and Quantum Cosmology · Physics 2026-04-29 S. A. Narawade , S. A. Kadam

This research investigates the impact of modified gravity on cosmic scales, focusing on $f(Q)$ cosmology. By applying energy conditions, the study reconstructs various $f(Q)$ models, considering an accelerating Universe, quintessence, and a…

General Relativity and Quantum Cosmology · Physics 2025-04-14 Irfan Mahmood , Hira Sohail , Allah Ditta , S. H. Shekh , Anil Kumar Yadav

The higher-curvature gravity with boundary terms i.e the $f(Q)$ theories, grounded on non-metricity as a fundamental geometric quantity, exhibit remarkable efficacy in portraying late-time universe phenomena. The aim is to delineate…

General Relativity and Quantum Cosmology · Physics 2024-02-20 Pooja Vishwakarma , Parth Shah

Based on General Relativity (GR) we consider two different cosmological scenarios in where reconstruct the energy exchange (Q) between cold dark matter (DM) fluid and dark energy (DE) fluid, which is modelled with a DE varying equation of…

General Relativity and Quantum Cosmology · Physics 2016-12-09 Freddy Cueva Solano

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

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

In this study, we investigate a locally rotationally symmetric (LRS) Bianchi type-I cosmological model in non-linear form of $f(Q)$ gravity with observational constraints. We solved the modified Einstein's field equations with a viscous…

General Relativity and Quantum Cosmology · Physics 2025-09-10 Dinesh Chandra Maurya

In this paper, we explore a theoretical and observational study of the presence of viscosity in the Unimodular Gravity formalism, a pioneering approach that, to the best of our knowledge, has not been previously explored in this context.…

General Relativity and Quantum Cosmology · Physics 2026-01-27 Norman Cruz , Esteban González

We consider a cosmological model with bulk viscosity ($\eta$) and variable cosmological $(\Lambda\propto \rho^{-\alpha}, \alpha=\rm const.$) and gravitational ($G$) constants. The model exhibits many interesting cosmological features.…

High Energy Physics - Theory · Physics 2008-11-26 Arbab I. Arbab

We present and constrain a cosmological model where the only component is a pressureless fluid with bulk viscosity as an explanation for the present accelerated expansion of the universe. We study the particular model of a bulk viscosity…

General Relativity and Quantum Cosmology · Physics 2009-01-05 Arturo Avelino , Ulises Nucamendi

In this study, we explored late-time cosmology within an extended class of theories based on $f(Q, L_m)$ gravity. This theory generalizes $f(Q)$ gravity by incorporating a non-minimal coupling between the non-metricity $Q$ and the matter…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-07 Kairat Myrzakulov , M. Koussour , O. Donmez , A. Cilli , E. Güdekli , J. Rayimbaev
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