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相关论文: A cosmological scenario from the Starobinsky model…

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

广义相对论与量子宇宙学 · 物理学 2017-01-05 P. H. R. S. Moraes , R. A. C. Correa , G. Ribeiro

In this work we present cosmological solutions from the simplest non-trivial $T$-dependence in $f(R,T)$ theory of gravity, with $R$ and $T$ standing for the Ricci scalar and trace of the energy-momentum tensor, respectively. Although such…

高能物理 - 理论 · 物理学 2016-06-29 P. H. R. S. Moraes , G. Ribeiro , R. A. C. Correa

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

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

A class of Kaluza-Klein cosmological models in $f(R,T)$ theory of gravity have been investigated. In the work, we have considered the functional $f(R,T)$ to be in the form $f(R,T)=f(R)+f(T)$ with $f(R)=\lambda R$ and $f(T)=\lambda T$. Such…

广义相对论与量子宇宙学 · 物理学 2016-07-14 P. K. Sahoo , B. Mishra , S. K. Tripathy

This article deals with a cosmological scenario in $ f(R,T) $ gravity for a flat FLRW model of the universe. We consider the $ f(R,T) $ function as $ f(R)+f(T) $ which starts with a quadratic correction of the geometric term $ f(R) $ having…

广义相对论与量子宇宙学 · 物理学 2022-05-03 Ritika Nagpal , J. K. Singh , A. Beesham , Hamid Shabani

This article presents cosmological models that arise in a subclass of $f(R,T)=f(R)+f(T)$ gravity models, with different $f(R)$ functions and fixed $T$-dependence. That is, the gravitational lagrangian is considered as $f(R,T)=f(R)+\lambda…

广义相对论与量子宇宙学 · 物理学 2018-09-18 P. K. Sahoo , P. H. R. S. Moraes , Parbati Sahoo , Binaya K. Bishi

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 this paper, we present the cosmological scenario obtained from $f(R,T)$ gravity by using an exponential dependence on the trace of the energy-momentum tensor. With a numerical approach applied to the equations of motion, we show several…

广义相对论与量子宇宙学 · 物理学 2019-11-11 G. Ribeiro , R. Sfair , P. H. R. S. Moraes , J. R. L. Santos , A. de Souza Dutra

We consider cosmological scenarios based on $f(R,T)$ theories of gravity ($R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor) and numerically reconstruct the function $f(R,T)$ which is able to reproduce the same…

广义相对论与量子宇宙学 · 物理学 2015-03-19 M. J. S. Houndjo , Oliver F. Piattella

We consider the $f(R,T)$ theory, where $R$ is the scalar curvature and $T$ is the trace of energy-momentum tensor, as an effective description for the holographic and new agegraphic dark energy and reconstruct the corresponding $f(R,T)$…

广义相对论与量子宇宙学 · 物理学 2013-10-04 M. Sharif , M. Zubair

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

We apply cosmological reconstruction methods to the $f(R,T)$ modified gravity, in its recently developed scalar-tensor representation. We do this analysis assuming a perfect fluid in a Friedmann-Lema\^{i}tre-Robsertson-Walker (FLRW)…

广义相对论与量子宇宙学 · 物理学 2024-07-24 Tiago B. Gonçalves , João Luís Rosa , Francisco S. N. Lobo

In this article, we have analysed the behaviour of scalar field and cosmological constant in $f(R,T)$ theory of gravity. Here, we have considered the simplest form of $f(R,T)$ i.e. $f(R,T)=R+2f(T)$, where $R$ is the Ricci scalar and $T$ is…

广义相对论与量子宇宙学 · 物理学 2016-07-15 G. P. Singh , Binaya K. Bishi , P. K. Sahoo

We examine the evolution of universe in $f(R,T)$ gravity where $R$ is the Ricci curvature and $T$ is the trace of energy momentum tensor. We focus on the specific form $f(R,T) = R+f(T)$ and explicitly find out the relation between $f(T)$…

广义相对论与量子宇宙学 · 物理学 2016-03-16 Gang Sun , Yong-Chang Huang

The $f(R,T)$ gravity models, for which $R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor, elevate the degrees of freedom of the renowned $f(R)$ theories, by making the Einstein field equations of the theory to also…

广义相对论与量子宇宙学 · 物理学 2024-02-28 J. A. S. Fortunato , P. H. R. S. Moraes , J. G. de Lima Júnior , E. Brito

We intend to study a new class of cosmological models in $f(R, T)$ modified theories of gravity, hence define the cosmological constant $\Lambda$ as a function of the trace of the stress energy-momentum-tensor $T$ and the Ricci scalar $R$,…

综合物理 · 物理学 2020-03-26 Safiqul Islam , Praveen Kumar , G. S. Khadekar , Tapas K Das

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

Kantowski-Sachs perfect fluid cosmological model is explored in modified gravity with functional form $f(R, T)$=$f_1(R)$+$f_2(T)$ where $R$ is Ricci scalar, and $T$ is the trace of the energy-momentum tensor. With this functional form,…

广义相对论与量子宇宙学 · 物理学 2023-04-26 T. Vinutha , K. Niharika , K. Sri Kavya

This study delves into modified gravity theories that are equivalent to General Relativity but involve the torsion or non-metricity scalar instead of the curvature scalar. Specifically, we focus on $f(Q,T)$ gravity, which entails an…

广义相对论与量子宇宙学 · 物理学 2023-11-22 N. Myrzakulov , M. Koussour , Alnadhief H. A. Alfedeel , H. M. Elkhair
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