中文
相关论文

相关论文: Late-Time Viscous Cosmology in $f(R,T)$ Gravity

200 篇论文

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…

综合物理 · 物理学 2026-03-24 M. Koussour , Alnadhief H. A. Alfedeel , S. Muminov , J. Rayimbaev

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…

宇宙学与河外天体物理 · 物理学 2024-05-14 M. Koussour , Abdelghani Errehymy , O. Donmez , K. Myrzakulov , M. A. Khan , B. Çil , E. Güdekli

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)…

宇宙学与河外天体物理 · 物理学 2025-01-14 Kairat Myrzakulov , O. Donmez , M. Koussour , S. Muminov , E. Davletov , J. Rayimbaev

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…

广义相对论与量子宇宙学 · 物理学 2021-12-01 Simran Arora , S. K. J. Pacif , Abhishek Parida , P. K. Sahoo

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…

广义相对论与量子宇宙学 · 物理学 2023-03-31 Lakhan V. Jaybhaye , Raja Solanki , Sanjay Mandal , Pradyumn Kumar Sahoo

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…

宇宙学与河外天体物理 · 物理学 2024-07-26 M. Koussour , A. Altaibayeva , S. Bekov , O. Donmez , S. Muminov , J. Rayimbaev

In this paper, we have investigated the late time cosmic acceleration issue in the context of $f(R,T)$ gravity. The matter field is considered to be that of viscous fluid. The model has been framed as a mathematical formalism and the effect…

广义相对论与量子宇宙学 · 物理学 2022-07-19 Sankarsan Tarai , Pratik P Ray , B. Mishra , S. K. Tripathy

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…

广义相对论与量子宇宙学 · 物理学 2024-03-06 Hamid Shabani , Norman Cruz , Amir Hadi Ziaie

This work explores the influence of viscous fluids on cosmological dynamics within the framework of General Relativity. We introduce a novel time-dependent parametrization for the bulk viscosity coefficient, given by \(\zeta = \zeta_0 (t -…

广义相对论与量子宇宙学 · 物理学 2025-04-30 Rajdeep Mazumdar , Mrinnoy M. Gohain , Kalyan Bhuyan

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…

广义相对论与量子宇宙学 · 物理学 2022-11-30 Jing Yang , Rui-Hui Lin , Xiang-Hua Zhai

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(…

广义相对论与量子宇宙学 · 物理学 2023-05-02 Raja Solanki , Dheeraj Singh Rana , Sanjay Mandal , P. K. Sahoo

In this paper, we investigate the late-time cosmic acceleration in mimetic $f(R,T)$ gravity with Lagrange multiplier and potential in a Universe containing, besides radiation and dark energy, a self-interacting (collisional) matter. We…

广义相对论与量子宇宙学 · 物理学 2017-11-22 E. H. Baffou , M. J. S. Houndjo , M. Hamani-Daouda , F. G. Alvarenga

In this paper, bulk viscosity is introduced in new holographic dark energy (HDE) to describe the effects of cosmic non-perfect fluid on the evolution of the universe in modified $f(R,T)$ gravity. Assuming $f(R,T)=R+\lambda T$, where $R$ is…

广义相对论与量子宇宙学 · 物理学 2018-04-17 C P Singh , Milan Srivastava

The problem of cosmic acceleration and dark energy is one of the mysteries presently posed in the scientific society that general relativity has not been able to solve. In this work, we have considered alternative models to explain this…

广义相对论与量子宇宙学 · 物理学 2022-12-01 M. Koussour , N. Myrzakulov , S. H. Shekh , M. Bennai

In this research paper, we explore a well-motivated parametrization of the time-dependent deceleration parameter, characterized by a cubic form, within the context of late time cosmic acceleration. The current analysis is based on the…

广义相对论与量子宇宙学 · 物理学 2023-12-19 Madhur Khurana , Himanshu Chaudhary , Saadia Mumtaz , S. K. J. Pacif , G. Mustafa

We propose a novel cosmological framework within the $f(R,T)$ type modified gravity theory, incorporating a non-minimally coupled with the higher order of the Ricci scalar ($R$) as well as the trace of the energy-momentum tensor ($T$).…

广义相对论与量子宇宙学 · 物理学 2024-02-06 Shaily , Akanksha Singh , J. K. Singh , Saibal Ray

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…

广义相对论与量子宇宙学 · 物理学 2021-12-13 Gaurav Gadbail , Simran Arora , P. K. Sahoo

We investigate the influence of bulk viscosity on late-time cosmic acceleration within an extended $f(Q, L_m)$ gravity framework, where the non-metricity $Q$ is non-minimally coupled with the matter Lagrangian $L_m$. Analyzing the function…

宇宙学与河外天体物理 · 物理学 2025-02-05 Y. Myrzakulov , O. Donmez , M. Koussour , S. Muminov , I. Y. Davletov , J. Rayimbaev

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…

广义相对论与量子宇宙学 · 物理学 2015-03-02 C. P. Singh , Pankaj Kumar

We investigate late-time cosmology in the context of modified $f(Q,L_m)$ gravity, considering a non-linear model$ f(Q,L_m) = \alpha Q + \beta L_m^n + \lambda$ where, $\alpha$, $\beta$, $\lambda$, and $n$ are some free parameters. The…

广义相对论与量子宇宙学 · 物理学 2026-01-16 Rajdeep Mazumdar , Kalyan Malakar , Kalyan Bhuyan
‹ 上一页 1 2 3 10 下一页 ›