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Related papers: Cosmology in scalar-tensor $f(R,T)$ gravity

200 papers

We present an explicit numerical implementation of the Friedmann equations to model the expansion of the Universe in spatially flat, homogeneous and isotropic Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmologies. Using cosmological…

Motivated by earlier works on reconstruction of modified gravity models with dark energy components, we extend them by considering a newly proposed model of (m, n)- type of holographic dark energy for two models of modified gravity, f(R)…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-14 M. Umar Farooq , Mubasher Jamil , Davood Momeni , Ratbay Myrzakulov

We consider flat Friedmann-Lema\^{\i}tre-Robertson-Walker cosmological models in the framework of general scalar-tensor theories of gravity with arbitrary coupling functions, set in the Jordan frame, in the cosmological epoch when the…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Laur Järv , Piret Kuusk , Margus Saal

We present a new family of exact vacuum solutions to Pfeifer and Wohlfarth's field equation in Finsler gravity, consisting of Finsler metrics that are Landsbergian but not Berwaldian, also known as unicorns due to their rarity.…

General Relativity and Quantum Cosmology · Physics 2023-09-27 Sjors Heefer , Christian Pfeifer , Antonio Reggio , Andrea Fuster

In this article, we explore some emerging properties of the stellar objects in the frame of the $f(R,T)$ gravity by employing the well-known Karmarkar condition, where $R$ and $T$ represent Ricci scalar and trace of energy momentum tensor…

General Relativity and Quantum Cosmology · Physics 2023-05-24 Zoya Asghar , M. Farasat Shamir , Ammara Usman , Adnan Malik

We analyze the quantum supersymmetric cosmological FRW model with a scalar field, with a conditional probability density and the scalar field identified as time. The Hilbert space has a spinorial structure and there is only one consistent…

General Relativity and Quantum Cosmology · Physics 2016-03-23 C. Ramírez , V. Vázquez-Báez

We discuss two aspects of f(R) theories of gravity in metric formalism. We first study the reasons to introduce a scalar-tensor representation for these theories and the behavior of this representation in the limit to General Relativity,…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Gonzalo J. Olmo

We study $f(R,T)$ gravity, in which the curvature $R$ appearing in the gravitational Lagrangian is replaced by an arbitrary function of the curvature and the trace $T$ of the stress-energy tensor. We focus primarily on situations where $f$…

General Relativity and Quantum Cosmology · Physics 2019-10-02 Sarah B. Fisher , Eric D. Carlson

We study the most general cosmological model with real scalar field which is minimally coupled to gravity. Our calculations are based on Friedmann-Lemaitre-Robertson-Walker (FLRW) background metric. Field equations consist of three…

General Relativity and Quantum Cosmology · Physics 2023-03-22 Medine Ildes , Metin Arik

The inflationary epoch and the late time acceleration of the expansion rate of universe can be explained by assuming a gravitationally coupled scalar field. In this article, we propose a new method of finding exact solutions in the…

General Relativity and Quantum Cosmology · Physics 2022-09-19 Albin Joseph , Rajib Saha

We construct the higher order terms of curvatures in Lagrangians of the scale factor for the Friedmann-Lemaitre-Robertson-Walker universe, which are linear in the second derivative of the scale factor with respect to cosmic time. It is…

General Relativity and Quantum Cosmology · Physics 2013-04-02 Nahomi Kan , Koichiro Kobayashi , Kiyoshi Shiraishi

In the case of a spatially flat Friedmann--Lema\^{\i}tre--Robertson--Walker universe in $f\left( R\right) $-gravity we write the Wheeler-DeWitt equation of quantum cosmology. The equation depends on the functional form of $f\left( R\right)…

General Relativity and Quantum Cosmology · Physics 2020-01-17 Andronikos Paliathanasis

In this paper we explore $f(T, \mathcal{T})$, where $T$ and $\mathcal{T}$ denote the torsion scalar and the trace of the energy-momentum tensor respectively. We impose the covariant conservation to the energy-momentum tensor and obtain a…

General Physics · Physics 2016-06-14 M. G. Ganiou , Ines G. Salako , M. J. S. Houndjo , J. Tossa

We investigate a flat FLRW-model in $f(R,T)$-gravity, which includes the quadratic variation in scalar curvature $R$ and the linear term of the trace of the stress-energy tensor $T$. In turn, we establish the model has the behaviour of the…

General Relativity and Quantum Cosmology · Physics 2022-08-10 J. K. Singh , Akanksha Singh , G. K. Goswami , J. Jena

We build upon previous investigation of the one-dimensional conformal symmetry of the Friedman-Lema\^ itre-Robertson-Walker (FLRW) cosmology of a free scalar field and make it explicit through a reformulation of the theory at the classical…

General Relativity and Quantum Cosmology · Physics 2020-05-27 Jibril Ben Achour , Etera R. Livine

We study scalar cosmological perturbations in $f(R, T)$ modified gravity theories being $T$ the trace of the energy-momentum tensor. We provide detailed equations for the matter energy density contrast. We solve then numerically to promote…

General Relativity and Quantum Cosmology · Physics 2024-08-28 Jonas Pinheiro da Silva , Hermano Velten

This article concerns with the characterization of a spacetime and modified gravity, such as $f\left(R,G\right)$, $f\left(R,T\right)$ and $f\left(R,L_{m}\right)$-gravity equipped with the projective curvature tensor. We establish that a…

General Relativity and Quantum Cosmology · Physics 2024-02-27 Young Jin Suh , Krishnendu De , Uday Chand De

In this letter, we investigate the cosmic expansion scenario of the universe in the framework of $f(R,L_m)$ gravity theory. We consider a non-linear $f(R,L_m)$ model, specifically, $f(R,L_m)=\frac{R}{2}+L_m^n + \beta$, where $n$ and $\beta$…

General Relativity and Quantum Cosmology · Physics 2023-11-02 Lakhan V. Jaybhaye , Raja Solanki , Sanjay Mandal , P. K. Sahoo

We investigate the cosmological dynamics of a homogeneous scalar field non-minimally coupled to torsion gravity, which also interacts with cold dark matter through energy and momentum transfer. The matter and radiation perfect fluids are…

General Relativity and Quantum Cosmology · Physics 2025-02-05 Carlos Rodriguez-Benites , Manuel Gonzalez-Espinoza , Giovanni Otalora , Manuel Alva-Morales

In this manuscript, we present a number of fascinating explicit reconstructions for the $f(Q)$ gravity from the background of Friedmann-La\^imatre-Robertson-Walker (FLRW) evolution history. We find the more general functions of…

General Relativity and Quantum Cosmology · Physics 2022-10-25 Gaurav N. Gadbail , Sanjay Mandal , P. K. Sahoo