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相关论文: Cosmological Dynamics of Modified Gravity With a N…

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We perform a phase space analysis of a generalized modified gravity theory with nonminimally coupling between geometry and matter. We apply the dynamical system approach to this generalized model and find that in the cosmological context,…

广义相对论与量子宇宙学 · 物理学 2016-05-17 Rui An , Xiaodong Xu , Bin Wang , Yungui Gong

Over the past century, General Relativity (GR) has been a cornerstone of gravitational theory. However, recent cosmological observations, such as the accelerated expansion of the Universe, challenge its completeness and the standard…

广义相对论与量子宇宙学 · 物理学 2025-06-02 Lakhan V. Jaybhaye

We study cosmologies in modified theories of gravity considering Lagrangian density $f(R)$ which is a polynomial function of scalar curvature ($R$) in the Einstein-Hilbert action in vacuum. The field equation obtained from the modified…

宇宙学与河外天体物理 · 物理学 2009-10-29 B. C. Paul , P. S. Debnath , S. Ghose

We present a novel theory of gravity by considering an extension of symmetric teleparallel gravity. This is done by introducing, in the framework of the metric-affine formalism, a new class of theories where the nonmetricity $Q$ is…

广义相对论与量子宇宙学 · 物理学 2018-10-31 Tiberiu Harko , Tomi S. Koivisto , Francisco S. N. Lobo , Gonzalo J. Olmo , Diego Rubiera-Garcia

In this work, we review a plethora of modified theories of gravity with generalized curvature-matter couplings. The explicit nonminimal couplings, for instance, between an arbitrary function of the scalar curvature $R$ and the Lagrangian…

广义相对论与量子宇宙学 · 物理学 2014-07-29 Tiberiu Harko , Francisco S. N. Lobo

In this paper, we investigate the accelerating phase of the Universe within the context of $f(R,L_m,T)$ gravity theory, where $R$, $L_m$, and $T$ represent the Ricci scalar, matter Lagrangian, and the trace of the energy-momentum tensor,…

广义相对论与量子宇宙学 · 物理学 2025-11-19 V. A. Kshirsagar , A. S. Agrawal , S. A. Kadam , Vishwajeet S. Goswami

We consider f(R,T) modified theory of gravity in which, in general, the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar and the trace of the energy-momentum tensor. We indicate that in this type of the theory,…

广义相对论与量子宇宙学 · 物理学 2016-10-05 Raziyeh Zaregonbadi , Mehrdad Farhoudi

In this proceeding, we review modified theories of gravity with a curvature-matter coupling between an arbitrary function of the scalar curvature and the Lagrangian density of matter. This explicit nonminimal coupling induces a…

广义相对论与量子宇宙学 · 物理学 2022-09-20 Francisco S. N. Lobo , Tiberiu Harko

We study new FRW type cosmological models of modified gravity treated on the background of Palatini approach. These models are generalization of Einstein gravity by the presence of a scalar field non-minimally coupled to the curvature. The…

广义相对论与量子宇宙学 · 物理学 2012-03-13 A. Borowiec , M. Kamionka , A. Kurek , M. Szydlowski

In this paper, we explore modified gravity in the framework of $f(R, \mathcal{L}_m)$ theories by reconstructing the function $f(\mathcal{L}_m)$, where $\mathcal{L}_m = \rho$ is the matter Lagrangian, under the assumption of a pressureless,…

广义相对论与量子宇宙学 · 物理学 2025-06-12 Y. Kalpana Devi , S. A. Narawade , B. Mishra

We consider the modified gravity non-minimally coupled with matter Lagrangian for the description of early-time and late-time universe. Such $F(R)$ ($F(G)$) gravity in the absence of non-minimal coupling is viable theory which passes the…

高能物理 - 理论 · 物理学 2008-11-26 Shin'ichi Nojiri , Sergei D. Odintsov , Petr V. Tretyakov

In this work, we investigate the cosmological dynamics of the $f(R, \mathcal{L}_m)$ gravity framework with a particular focus on the contributions of the scalar field. Considering a functional form that includes linear and exponential…

广义相对论与量子宇宙学 · 物理学 2026-04-01 Y. Kalpana Devi , Rahul Bhagat , B. Mishra

In this work a new non-minimally coupled model is presented, where a generic function $f(R)$ of the scalar curvature factors the usual Einstein-Hilbert action functional, motivated by relevant results obtained from similar models. Its…

广义相对论与量子宇宙学 · 物理学 2016-11-22 R. P. L. Azevedo , J. Páramos

A modified f(G) gravity model with coupling between matter and geometry is proposed, which is described by the product of the Lagrange density of the matter and an arbitrary function of the Gauss-Bonnet term. The field equations and the…

宇宙学与河外天体物理 · 物理学 2015-06-04 Yue-Yue Zhao , Ya-Bo Wu , Jianbo Lu , Zhuo Zhang , Wei-Li Han , Liang-Liang Ling

The evolution of density perturbations is analysed in a modified theory of gravity with a nonminimal coupling between curvature and matter. We consider the broken degeneracy between the choices of matter Lagrangian for a perfect fluid,…

广义相对论与量子宇宙学 · 物理学 2026-01-26 Miguel Barroso Varela , Orfeu Bertolami

In this work, we further study a metric modified theory of gravity which contains a non-minimal coupling to matter, more precisely, we assume two functions of the scalar curvature, $f_1$ and $f_2$, where the first one generalises the…

广义相对论与量子宇宙学 · 物理学 2021-03-31 María Ortiz-Baños , Mariam Bouhmadi-López , Ruth Lazkoz , Vincenzo Salzano

In this article, we examine the dynamical evolution of flat FRW cosmological model in $f(R, L_m)$ gravity theory. We consider the general form of $f(R, L_m)$ defined as $f(R, L_m) = \Lambda + \frac{\alpha}{2} R + \beta L_m^n$, where…

广义相对论与量子宇宙学 · 物理学 2025-02-14 Aman Shukla , Rakesh Raushan , Raghavendra Chaubey

We develop the general scheme for modified $f(R)$ gravity reconstruction from any realistic FRW cosmology. We formulate several versions of modified gravity compatible with Solar System tests where the following sequence of cosmological…

高能物理 - 理论 · 物理学 2008-11-26 Shin'ichi Nojiri , Sergei D. Odintsov

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

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
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