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相关论文: EDSFD parametrization in $ f(R,T) $ gravity with l…

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The present research paper is an investigation of dark energy nature of logarithmic $f(R, T)$-gravity cosmology in a flat FLRW space-time universe. We have derived modified Einstein's field equations for the function $f(R, T)=R-16\pi…

广义相对论与量子宇宙学 · 物理学 2023-06-06 Dinesh Chandra Maurya , Jagat Singh , Lalit Kumar Gaur

In this paper, we have investigated some exact cosmological models in Myrzakulov gravity using a flat Friedmann-Lematre-Robertson-Walker (FLRW) spacetime metric. We have considered the modified Lagrangian function as $F(R,T)=R+\lambda T$,…

广义相对论与量子宇宙学 · 物理学 2024-08-14 Dinesh Chandra Maurya , Ratbay Myrzakulov

This cosmological model is a study of modified $f(Q,T)$ theory of gravity which was recently proposed by Xu {\it et al.} (Eur. Phys. J. C {\bf 79}, 708 (2019)). In this theory of gravity, the action contains an arbitrary function $f(Q,T)$…

综合物理 · 物理学 2021-09-03 Anirudh Pradhan , Archana Dixit

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

Recently, it was formulated a teleparallel theory called $f(T,B)$ gravity which connects both $f(T)$ and $f(R)$ under suitable limits. In this theory, the function in the action is assumed to depend on the torsion scalar $T$ and also on a…

广义相对论与量子宇宙学 · 物理学 2017-12-19 Sebastian Bahamonde , M. Zubair , G. Abbas

In this work, we consider four $f(R)$ gravity models -- the Hu-Sawicki, Starobinsky, Exponential and Tsujikawa models -- and use a range of cosmological data, together with Markov Chain Monte Carlo sampling techniques, to constrain the…

宇宙学与河外天体物理 · 物理学 2022-01-05 Christine R. Farrugia , Joseph Sultana , Jurgen Mifsud

In this paper, we consider the flat Friedmann Lematre Robertson-Walke metric in the presence of perfect fluid models and extended $f(R,G,T)$ gravity (where $R$ is the Ricci scalar, $G$ is the Gauss Bonnet invariant and $T$ stands for trace…

广义相对论与量子宇宙学 · 物理学 2022-12-21 M. Ilyas , Aftab Ahmad , Fawad Khan , M. Wasif

In this work, we use reconstruction methods to obtain cosmological solutions in the recently developed scalar-tensor representation of $f(R,T)$ gravity. Assuming that matter is described by an isotropic perfect fluid and the spacetime is…

广义相对论与量子宇宙学 · 物理学 2022-03-15 Tiago B. Gonçalves , João Luís Rosa , Francisco S. N. Lobo

In the recently suggested modified non-metricity gravity theory with boundary terms in a flat FLRWspacetime universe, dark energy scenarios of cosmological models are examined in this study. An arbitrary function, $f(Q, C)=Q+{\alpha}C^{2}$,…

广义相对论与量子宇宙学 · 物理学 2023-10-05 Anirudh Pradhan , Archana Dixit , M. Zeyauddin , S. Krishnannair

In this paper we describe two different parametrizations of field equations in the $f(R)$ theories of gravity and two resulting parametrizations of the Friedmann Equations. In particular we show how these two parametrizations lead to two…

广义相对论与量子宇宙学 · 物理学 2015-10-05 Liberato Pizza

In this letter, we investigate cosmology within the framework of modified $f(Q, L_m)$ gravity using the non-linear model $f(Q, L_m) = -Q + \alpha L_m^n + \beta$, where $\alpha$, $\beta$, and $n$ are free parameters. The modified Friedmann…

宇宙学与河外天体物理 · 物理学 2025-05-02 Y. Myrzakulov , Alnadhief H. A. Alfedeel , M. Koussour , S. Muminov , E. I. Hassan , J. Rayimbaev

In this study, we have explored a transitioning cosmological model of universe's expansion in $f(R,\mathcal{L}_{m})$ gravity. The quadratic type of equation of state parameter in the form $\omega=-1 + \alpha (1 + z) + \beta (1 + z)^2$,…

广义相对论与量子宇宙学 · 物理学 2025-04-16 Vinod Kumar Bhardwaj , Saibal Ray

This research paper deals with a transit dark energy cosmological model in $f(R, L_{m})$-gravity with observational constraints. For this, we consider a flat FLRW space-time and have taken a cosmological cosntant-like parameter $\beta$ in…

广义相对论与量子宇宙学 · 物理学 2023-05-03 Anirudh Pradhan , Dinesh Chandra Maurya , Gopikant K. Goswami , Aroonkumar Beesham

The cosmic curvature density parameter has been constrained in the present work independent of any background cosmological model. The reconstruction is performed adopting the non-parametric Gaussian Processes (GP). The constraints on…

宇宙学与河外天体物理 · 物理学 2022-03-18 Purba Mukherjee , Narayan Banerjee

In this work, we analyse the late-time evolution of the universe for a particular $f(R)$ gravity model built from an exponential function of the scalar curvature. Following the literature, we write the field equations in terms of a suited…

广义相对论与量子宇宙学 · 物理学 2023-10-18 A. Oliveros , Mario A. Acero

In this paper, we have explored the field equations of $f(T,B)$ gravity and determined the dynamical parameters with the hyperbolic function of Hubble parameter. The accelerating behavior has been observed and the behavior of equation of…

广义相对论与量子宇宙学 · 物理学 2022-07-22 S. A. Kadam , B. Mishra , S. K. Tripathy

A novel function for modified gravity is proposed, $f(R, T)=R+\lambda R^2+2\beta\ln(T)$, with constants $\lambda$ and $\beta$, scalar curvature $R$, and the trace of stress energy tensor $T$, satisfying $T=\rho-3p>0$. Subsequently, two…

综合物理 · 物理学 2020-06-16 Emilio Elizalde , Nisha Godani , Gauranga C. Samanta

In this manuscript, we consider the extension of the Hilbert-Einstein action to analyze several interesting features of the theory. More specifically, the Lagrangian $f(R)$ is replaced by $f(R, L_m)$ in action, where $R$ is the Ricci…

广义相对论与量子宇宙学 · 物理学 2022-03-25 Lakhan V. Jaybhaye , Sanjay Mandal , P. K. Sahoo

We show that modelling the universe as a pre-geometric system with emergent quantum modes, and then constructing the classical limit, we obtain a new account of space and gravity that goes beyond Newtonian gravity even in the…

综合物理 · 物理学 2007-09-20 Reginald T Cahill

In this study, we investigate the cosmological history within the framework of modified $f(Q)$ gravity, which proposes an alternative theory of gravity where the gravitational force is described by a non-metricity scalar. By employing a…

广义相对论与量子宇宙学 · 物理学 2023-08-30 N. Myrzakulov , M. Koussour , A. Mussatayeva