中文
相关论文

相关论文: Exploring stable models in $f(R; T; R_{\mu\nu} T^{…

200 篇论文

The aim of this paper is to reconstruct and analyze the stability of some cosmological models against linear perturbations in $f(\mathcal{G},T)$ gravity ($\mathcal{G}$ and $T$ represent the Gauss-Bonnet invariant and trace of the…

广义相对论与量子宇宙学 · 物理学 2017-06-22 M. Sharif , Ayesha Ikram

We consider $f(R, T)$ theory of gravity, where $R$ is the curvature scalar and $T$ the trace of the energy momentum tensor. Attention is attached to the special case, $f(R, T)= R+2f(T)$ and two expressions are assumed for the function…

广义相对论与量子宇宙学 · 物理学 2015-06-05 F. G. Alvarenga , M. J. S. Houndjo , A. V. Monwanou , Jean B. Chabi Orou

In this paper we undertake the modified theory of gravity f(R,T) where R and T are the Ricci scalar and the trace of the energy momentum tensor, respectively. Imposing the conservation of the energy momentum tensor, we obtain a model about…

广义相对论与量子宇宙学 · 物理学 2015-06-30 E. H. Baffou , A. V. Kpadonou , M. E. Rodrigues , M. J. S. Houndjo , J. Tossa

This paper investigates the existence and stability of Einstein universe in the context of $f(R,T,Q)$ gravity, where $Q=R_{\mu\nu}T^{\mu\nu}$. Considering linear homogeneous perturbations around scale factor and energy density, we formulate…

广义相对论与量子宇宙学 · 物理学 2018-12-19 M. Sharif , Arfa Waseem

We propose a new model of modified $F(R)$ gravity theory with the function $F(R) = (1/\beta) \arcsin(\beta R)$. Constant curvature solutions corresponding to the flat and de Sitter spacetime are obtained. The Jordan and Einstein frames are…

综合物理 · 物理学 2015-07-24 S. I. Kruglov

We study a new type of the modified teleparallel gravity of the form $F(T,\,\Theta)$ in which $T$, the torsion scalar, is coupled with $\Theta$, the trace of the stress-energy tensor. In a perturbational approach, we study the stability of…

广义相对论与量子宇宙学 · 物理学 2015-06-17 Faeze Kiani , Kourosh Nozari

The aim of this paper is to investigate the stable/unstable regimes of the non-static anisotropic filamentary stellar models in the framework of $f(R,T,R_{\mu\nu}T^{\mu\nu})$ gravity. We construct the field equations and conservation laws…

综合物理 · 物理学 2017-06-22 Z. Yousaf , M. Zaeem-ul-Haq Bhatti , Ume Farwa

Here we propose the extended modified gravity theory named as $f(R,G,\mathcal{T})$ gravity where $R$ is the Ricci scalar, $G$ is the Gauss-Bonnet invariant and $\mathcal{T}$ is the trace of the stress-energy tensor. We derive the…

广义相对论与量子宇宙学 · 物理学 2020-12-02 Ujjal Debnath

In this paper, we have emphasized the stability analysis of the accelerating cosmological models obtained in $f(T)$ gravity theory. The behavior of the models based on the evolution of the equation of state parameter shows phantom-like…

广义相对论与量子宇宙学 · 物理学 2022-05-25 L. K. Duchaniya , Santosh V Lohakare , B. Mishra , S. K. Tripathy

In literature there is a model of modified gravity in which the matter Lagrangian is coupled to the geometry via trace of the stress-energy momentum tensor $T=T_{\mu}^{\mu}$. This type of modified gravity is called as $f(R,T)$ in which $R$…

广义相对论与量子宇宙学 · 物理学 2016-08-30 M. J. S. Houndjo , M. E. Rodrigues , N. S. Mazhari , D. Momeni , R. Myrzakulov

Motivated by the dark energy issue, a minisuperspace approach to the stability for modified gravitational models in a four dimensional cosmological setting are investigated. Specifically, after revisiting the $f(R)$ case, $R$ being the…

广义相对论与量子宇宙学 · 物理学 2008-11-26 Guido Cognola , Monica Gastaldi , Sergio Zerbini

In this study, we explore the dynamics of the universe using a modified gravity model represented by $f(R, G, T)$, where $R$ is the Ricci scalar, $G$ is the Gauss-Bonnet invariant, and $T$ is the trace of the stress-energy tensor. The model…

广义相对论与量子宇宙学 · 物理学 2025-03-27 Farzad Milani

This paper explores stability of the Einstein universe against linear homogeneous perturbations in the background of $f(\mathcal{G},T)$ gravity. We construct static as well as perturbed field equations and investigate stability regions for…

广义相对论与量子宇宙学 · 物理学 2017-07-26 M. Sharif , Ayesha Ikram

In this work, we investigate for an analytical solution under modified gravity theory, specifically the $f(R,T)$ gravity for two different eras, i.e., matter and dark energy dominated accelerating universe from completely geometrical and…

广义相对论与量子宇宙学 · 物理学 2023-12-12 Arijit Panda , Surajit Das , Goutam Manna , Saibal Ray

We investigated the stability condition in $f(T,\phi)$ gravity theory for considering two models by using dynamical system. We assume the forms of $G(T)$ are $(i)$ $G(T)$ = $\alpha T+\frac{\beta}{T}$, $(ii)$ $G(T)$ = $\zeta T$ ln$(\psi T)$,…

广义相对论与量子宇宙学 · 物理学 2023-06-14 Amit Samaddar , S. Surendra Singh

Conditions for the existence and stability of de Sitter space in modified gravity are derived by considering inhomogeneous perturbations in a gauge-invariant formalism. The stability condition coincides with the corresponding condition for…

广义相对论与量子宇宙学 · 物理学 2008-11-26 Valerio Faraoni , Shahn Nadeau

Dynamical analysis of spherically symmetric collapsing star surrounding in locally anisotropic environment with expansion-free condition is presented in $f(R,T)$ gravity, where $R$ corresponds to Ricci scalar and $T$ stands for the trace of…

广义相对论与量子宇宙学 · 物理学 2015-04-21 Ifra Noureen , M. Zubair

Within the context of modified gravity and dark energy scenarios of the accelerating universe, we study the stability of de Sitter space with respect to inhomogeneous perturbations using a gauge-independent formalism. In modified gravity…

广义相对论与量子宇宙学 · 物理学 2009-11-11 Valerio Faraoni

In this paper, we investigate the stability of the flat FLRW metric in $f(T)$ gravity. This is achieved by analysing the small perturbations, $\delta$ about the Hubble parameter and the matter energy density, $\delta_\text{m}$. We find that…

广义相对论与量子宇宙学 · 物理学 2017-01-03 Gabriel Farrugia , Jackson Levi Said

We analyze the stability of the Einstein static universe by considering homogeneous scalar perturbations in the context of f(R) modified theories of gravity. By considering specific forms of f(R), the stability regions of the solutions are…

广义相对论与量子宇宙学 · 物理学 2012-06-22 Christian G. Boehmer , Lukas Hollenstein , Francisco S. N. Lobo
‹ 上一页 1 2 3 10 下一页 ›