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相关论文: Late-time cosmology in a model of modified gravity…

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Since viable $f(R)$ gravity models must reconcile early-universe inflation with late-time acceleration, we specifically study the dynamical behavior of such a theory during the matter-dominated to dark-energy-dominated transition epoch. By…

宇宙学与河外天体物理 · 物理学 2026-03-03 Siqi He , Weiqiang Yang , Hangyi Jin

In this research work, we explore the late-time accelerated expansion of the universe within the framework of modified gravity, specifically $f(R, L_m)$ theory, by considering two non-linear models: $f(R, L_{m}) = \frac{R}{2}+(1+\eta R)…

广义相对论与量子宇宙学 · 物理学 2025-06-23 Khomesh R. Patle , G. P. Singh , Romanshu Garg

We have probed a cosmological model in $f(R)$-gravity, which is a cubic equation in scalar curvature $R$. The terms arise due to nonlinear $f(R)$ function are treated as energy due to curvature inspired geometry. As a result, we find…

广义相对论与量子宇宙学 · 物理学 2023-05-03 G. K. Goswami , Rita Rani , Harshna Balhara , J. K. Singh

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…

广义相对论与量子宇宙学 · 物理学 2025-04-23 Bikash Chandra Roy , Aroonkumar Beesham , Bikash Chandra Paul

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 +…

宇宙学与河外天体物理 · 物理学 2026-03-05 Shambel Sahlu , Alnadhief H. A. Alfedeel , Amare Abebe

We explore the late time cosmological dynamics of the Universe within the framework of $f(Q,\mathcal{L}_{m})$ gravity by considering the specific form $f(Q, \mathcal{L}_m)=-Q+2\mathcal{L}_m+\gamma$. To describe the cosmic pressure…

广义相对论与量子宇宙学 · 物理学 2025-08-08 Amit Samaddar , S. Surendra Singh

Modified gravity theories have received increased attention lately to understand the late time acceleration of the universe. This viewpoint essentially modifies the geometric components of the universe. Among numerous extension to…

广义相对论与量子宇宙学 · 物理学 2019-05-23 Parth Shah , Gauranga C. Samanta

We study cosmological evolution in a flat FLRW spacetime in the context of modified STEGR gravity or $f(Q)$, using an exponential two-parameter model which represents a smooth perturbative expansion around the $\Lambda$CDM model. The…

广义相对论与量子宇宙学 · 物理学 2025-04-15 Ivan R. Vasquez , A. Oliveros

In this letter, we investigate the cosmic expansion scenario of the universe in the framework of $f(R,L_m)$ gravity theory. We consider a non-linear $f(R,L_m)$ model, specifically, $f(R,L_m)=\frac{R}{2}+L_m^n + \beta$, where $n$ and $\beta$…

广义相对论与量子宇宙学 · 物理学 2023-11-02 Lakhan V. Jaybhaye , Raja Solanki , Sanjay Mandal , P. K. Sahoo

The role of an exponential function of the scalar curvature in the modified gravity is analyzed. Two models are proposed. A toy model that complies with local and cosmological constraints and gives appropriate qualitative description of the…

广义相对论与量子宇宙学 · 物理学 2020-07-15 L. N. Granda

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

In this investigation, we perform an observational statistical analysis in the theory of $ f(R, L_m) $ gravity. The proposed theoretical model is based on the Ricci scalar's non-linear contribution. We use a distinct parameterization for…

广义相对论与量子宇宙学 · 物理学 2024-08-30 J. K. Singh , Shaily , Akanksha Singh , Harshna Balhara , Joao R. L. Santos

We study the late-time evolution of the Universe within the f(R,G) gravity framework, where R is the Ricci scalar and G is the Gauss-Bonnet term. To make the model tractable, we propose a parametrization scheme and determine its parameters…

广义相对论与量子宇宙学 · 物理学 2026-05-12 Santosh V. Lohakare , B. Mishra , S. K. Maurya

We probe the cosmic expansion scenario within the framework of $f(R, L_{m})$ gravity by employing a well-motivated functional form of $f(R, L_{m}) = \frac{R}{2} + L_{m}^{\lambda}$. Specifically, we introduce three novel cosmological models…

广义相对论与量子宇宙学 · 物理学 2026-05-27 Khomesh R. Patle , G. P. Singh

This thesis focuses on late-time cosmic acceleration within modified theories of gravity, using various observational data sets and statistical analysis. The Universe is assumed to be spatially homogeneous and isotropic and is described by…

广义相对论与量子宇宙学 · 物理学 2025-03-05 Santosh V. Lohakare

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

In this work, we study the late-time cosmological solutions of f(R,T)=g(R)+h(-T) models assuming that the conservation of the energy-momentum tensor (EMT) is violated. We perform our analysis through constructing an autonomous dynamical…

广义相对论与量子宇宙学 · 物理学 2017-08-07 Hamid Shabani , Amir Hadi ziaie

We consider the field equations for a flat FRW cosmological model, in a generic $f(R)$ gravity model and cast them into a, completely normalized-dimensionless, system of O.D.Es for the scale factor and the function $f(R)$, with respect to…

广义相对论与量子宇宙学 · 物理学 2018-01-24 A. Kuiroukidis

This work examines the cosmological implications of two functional forms of $f(R,T) = R + \alpha T^n$ gravity: for two different value of $n $ where $n=1$ and $n\neq 1$, and $\alpha$ and $n$ are free parameters. The modified Friedmann…

宇宙学与河外天体物理 · 物理学 2026-02-24 Mustapha Lamaaoune

In this work we shall study the late-time behavior of $k$-Essence $f(R)$ gravity without scalar potential, in the presence of matter and radiation perfect fluids. We quantify the late-time study by using the statefinder function…

广义相对论与量子宇宙学 · 物理学 2020-04-21 S. D. Odintsov , V. K. Oikonomou , F. P. Fronimos
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