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相关论文: Bounds on Higher Derivative $f(R,\square R,T)$ Mod…

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In this paper, we examined the viability bounds of a higher derivative $f(R,\Box R, T)$ theory through analyzing energy conditions (where $R$ and $T$ are the Ricci scalar and trace of energy momentum tensor, respectively). We take flat…

广义相对论与量子宇宙学 · 物理学 2018-06-26 Z. Yousaf , M. Sharif , M. Ilyas , M. Z. Bhatti

This paper is devoted to study the energy conditions in F(R,T) gravity for FRW universe with perfect fluid, where $R$ is the Ricci scalar and $T$ is the torsion scalar. We construct the general energy conditions in this theory and reduce…

广义相对论与量子宇宙学 · 物理学 2013-10-23 M. Sharif , S. Rani , R. Myrzakulov

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

The basic aim of this manuscript is to investigate the cosmological solutions in the context of the modified $f(R, T)$ theory of gravity, where $R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor. For our current…

广义相对论与量子宇宙学 · 物理学 2024-03-26 Adnan Malik , Tayyaba Naz , Aimen Rauf , M. Farasat Shamir , Z. Yousaf

In the present paper, we have investigated the Friedmann Robertson Walker (FRW) model in viable $f(R,T)$ gravity with $f(R,T)$ function proposed as $f(R,T)=R +\xi T^{1/2}$, where $\xi$ is an arbitrary constant, $R$ is the scalar curvature…

综合物理 · 物理学 2020-08-26 Nisha Godani , Gauranga C. Samanta

We have investigated an isotropic and homogeneous cosmological model of the universe in $f(R, T^{\phi})$ gravity, where $T^{\phi}$ is the trace of the energy-momentum tensor and $R$ is the Ricci scalar. We developed and presented exact…

广义相对论与量子宇宙学 · 物理学 2023-08-10 Vinod Kumar Bhardwaj , Priyanka Garg

We investigate cosmological solutions of f(R,T) modified theories of gravity for perfect fluid in spatially FLRW metric through phase space analysis, where R is Ricci scalar and T denotes the trace of energy-momentum tensor of matter…

广义相对论与量子宇宙学 · 物理学 2017-05-23 Hamid Shabani , Mehrdad Farhoudi

The energy conditions are derived in the context of $f(R,T)$ gravity, where $R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor, which can reduce to the well-known conditions in $f(R)$ gravity and general relativity.…

广义相对论与量子宇宙学 · 物理学 2015-06-11 Muhammad Sharif , Muhammad Zubair

Various models are under consideration with metric type flat FRW whose energy-momentum tensor is described by a perfect fluid whose generic equation state and taking into account the conservation principle, but considering some of the…

综合物理 · 物理学 2007-05-23 J. A. Belinchon

We construct the energy conditions for the recently proposed $f(R,L,T)$ gravity theory, for which $f$ is a generic function of the Ricci scalar $R$, matter lagrangian density $L$ and trace of the energy-momentum tensor $T$. We analyse two…

广义相对论与量子宇宙学 · 物理学 2024-06-25 Simran Arora , P. H. R. S. Moraes , P. K. Sahoo

In general relativity, the energy conditions are invoked to restrict general energy-momentum tensors on physical grounds. We show that in the standard Friedmann-Lemaitre-Robertson-Walker approach to cosmological modelling where the equation…

天体物理学 · 物理学 2009-11-11 J. Santos , J. S. Alcaniz , M. J. Reboucas

We study the energy conditions in the framework of the modi- fied gravity with higher-derivative torsional terms in the action. We discuss the viability of the model by studying the energy conditions in terms of the cosmographical…

广义相对论与量子宇宙学 · 物理学 2017-06-07 Tahereh Azizi , Miysam Gorjizadeh

The study of energy conditions has many significant applications in general relativistic and cosmological contexts. This paper explores the energy conditions in the framework of the most general scalar-tensor theory with field equations…

广义相对论与量子宇宙学 · 物理学 2013-11-27 M. Sharif , Saira Waheed

In the present article, we developed a dynamical system in the context of modified $f(R,G,T)$ gravity, where $R$, $G$ and $T$ are Ricci scalar, Gauss-Bonnet term and energy-momentum tensor respectively. Development of the dynamical system…

广义相对论与量子宇宙学 · 物理学 2025-05-30 Elangbam Chingkheinganba Meetei , S. Surendra Singh

We propose a new theoretical approach for a cosmological model, which starts from an exponential of the trace of the energy-momentum tensor-dependence on the gravitational action, to be summed to the Ricci scalar. We derive the referred…

广义相对论与量子宇宙学 · 物理学 2020-04-08 P. H. R. S. Moraes , P. K. Sahoo , S. K. J. Pacif

In this paper, we have considered flat Friedmann-Lema\^{i}tre-Robertson-Walker metric in the framework of perfect fluid models and modified $f(G)$ gravity (where $G$ is the Gauss Bonnet invariant). Particularly, we have considered…

广义相对论与量子宇宙学 · 物理学 2017-08-08 Kazuharu Bamba , M. Ilyas , M. Z. Bhatti , Z. Yousaf

In this paper we derive a novel cosmological model from the $f(R,T)$ theory of gravitation, for which $R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor. We consider the functional form $f(R,T)=f(R)+f(T)$, with…

广义相对论与量子宇宙学 · 物理学 2019-06-04 P. H. R. S. Moraes , P. K. Sahoo , G. Ribeiro , R. A. C. Correa

We derive the conditions under which dark energy models whose Lagrangian densities f are written in terms of the Ricci scalar R are cosmologically viable. We show that the cosmological behavior of f(R) models can be understood by a…

广义相对论与量子宇宙学 · 物理学 2008-11-26 Luca Amendola , Radouane Gannouji , David Polarski , Shinji Tsujikawa

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

Motivated by recent work on consistent fluid couplings in $f(R, T)$ gravity, we study cosmology in the nontrivial model $f(R, T) = R + \sigma R T$ using the Brown variational principle for a barotropic perfect fluid. For a flat FLRW…

广义相对论与量子宇宙学 · 物理学 2026-05-15 Davide Batic , Christian G. Boehmer , Denys Dutykh
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