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Related papers: Viscous cosmology in the Weyl-type $f(Q,T)$ gravit…

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We have studied bulk viscosity in the modified $f(Q, T)$ gravity theory formalism, where $Q$ represents the non-metricity and $T$ denotes the trace of energy-momentum tensor within a flat Friedmann-Lema\^{i}tre-Robertson-Walker metric…

General Relativity and Quantum Cosmology · Physics 2021-12-01 Simran Arora , S. K. J. Pacif , Abhishek Parida , P. K. Sahoo

In this article, we have investigated the role of bulk viscosity to study the accelerated expansion of the universe in the framework of modified $f(Q)$ gravity. The gravitational action in this modified gravity theory has the form $f(Q)$,…

General Relativity and Quantum Cosmology · Physics 2022-07-20 Raja Solanki , S. K. J. Pacif , Abhishek Parida , P. K. Sahoo

In this paper, we have studied the dynamical aspects of the cosmological model of the Universe in the Weyl type $f(Q,T)$ gravity, which is an extension of symmetric teleparallel gravity. The non-metricity scalar $Q$ has been expressed in…

General Relativity and Quantum Cosmology · Physics 2023-06-02 Rahul Bhagat , S. A. Narawade , B. Mishra

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

We propose a new model for the viscosity of cosmic matters, which can be applied to different epochs of the universe. Using this model, we include the bulk viscosities as practical corrections to the perfect fluid models of the baryonic and…

General Relativity and Quantum Cosmology · Physics 2022-11-30 Jing Yang , Rui-Hui Lin , Xiang-Hua Zhai

In this paper, we investigate the effects of varying bulk viscosity coefficients $\zeta(t)=\zeta_{0}+\zeta_{1}H$ on cosmic evolution within the framework of $f(T)$ teleparallel gravity. We focus on two cases: (i) $\zeta_{1} \neq0$ and (ii)…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-14 Kairat Myrzakulov , O. Donmez , M. Koussour , S. Muminov , E. Davletov , J. Rayimbaev

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

In this paper we have investigated a bulk viscous universe in $f(R,T)$ gravity where $R$ and $T$ are the Ricci scalar and trace of energy momentum tensor respectively. We have obtained explicit solutions of field equations in modified…

General Physics · Physics 2020-03-03 Anil Kumar Yadav , Lokesh Kumar Sharma , B. K. Singh , P. K. Sahoo

In this work, we investigate the dynamics of bouncing cosmologies within the framework of Weyl-type $f(Q,T)$ gravity. Here, $Q$ represents the non-metricity of the space-time, is determined by the vector field $w_\mu$, while $T$ represents…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-25 A. Zhadyranova , M. Koussour , S. Bekkhozhayev

This study investigates the dynamics of a spatially homogeneous and anisotropic LRS Bianchi type-I universe with viscous fluid in the framework of $f(Q)$ symmetric teleparallel gravity. We assume a linear form for $f(Q)$ and introduce…

General Relativity and Quantum Cosmology · Physics 2024-04-16 M. Koussour , S. H. Shekh , M. Bennai , N. Myrzakulov

In this manuscript, we analyze the viscous fluid cosmological model in the framework of recently proposed $f(Q)$ gravity by assuming three different forms of bulk viscosity coefficients, specifically, $(i)\zeta =\zeta_{0}+\zeta_{1}\left(…

General Relativity and Quantum Cosmology · Physics 2023-05-02 Raja Solanki , Dheeraj Singh Rana , Sanjay Mandal , P. K. Sahoo

Gravity is attributed to the spacetime curvature in classical General Relativity (GR). But, other equivalent formulation or representations of GR, such as torsion or non-metricity have altered the perception. We consider the Weyl-type $f(Q,…

General Relativity and Quantum Cosmology · Physics 2021-10-20 Gaurav Gadbail , Simran Arora , P. K. Sahoo

Using the cosmological date sets, the cosmological parameters are constrained in this paper, with some well known form of Hubble parameter. To understand the dynamics of the Weyl type $f(Q,T)$, functional form $f(Q,T)$ has been introduced,…

General Relativity and Quantum Cosmology · Physics 2024-09-05 Rahul Bhagat , B. Mishra

In the present study, we explore the dynamical characteristics of the quintessence cosmological model in Weyl-type $f(Q,T)$ gravity. Here, $T$ represents the trace of the matter energy-momentum tensor, and $Q$ symbolizes the nonmetricity…

General Relativity and Quantum Cosmology · Physics 2023-10-05 Vinod Kumar Bhardwaj , Priyanka Garg

In this paper, we investigate a cosmological model based on viscous $f(R,T)$ gravity as a potential alternative to dark energy. This model incorporates bulk viscosity and is analyzed using an effective equation of state. We consider the…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-26 M. Koussour , A. Altaibayeva , S. Bekov , O. Donmez , S. Muminov , J. Rayimbaev

In this study, we explore the accelerated expansion of the universe within the framework of modified $f(Q)$ gravity. The investigation focus on the role of bulk viscosity in understanding the universe's accelerated expansion. Specifically,…

General Relativity and Quantum Cosmology · Physics 2024-07-09 Dheeraj Singh Rana , P. K. Sahoo

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

The standard formulation of General Relativity Theory, in the absence of a cosmological constant, is unable to explain the responsible mechanism for the observed late-time cosmic acceleration. On the other hand, by inserting the…

General Relativity and Quantum Cosmology · Physics 2022-12-26 Raja Solanki , Simran Arora , P. K. Sahoo , P. H. R. S. Moraes

In this study, we investigate the dynamics of the Universe during the observed late-time acceleration phase within the framework of the Weyl-type $f(Q,T)$ theory. Specifically, we consider a well-motivated model with the functional form…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-23 M. Koussour , S. Myrzakulova , N. Myrzakulov

We consider the influence of the perturbative bulk viscosity on the evolution of the Hubble parameter in the QCD era of the early Universe. For the geometry of the Universe we assume the homogeneous and isotropic…

General Relativity and Quantum Cosmology · Physics 2010-11-24 A. Tawfik , M. Wahba , H. Mansour , T. Harko
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