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Related papers: Cosmological models in $f(R,T)$-$\Lambda(\phi)$ gr…

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We investigate inflation within $f(R,\phi)$-theories, where a dynamical scalar field is coupled to gravity. A class of models which can support early-time acceleration with the emerging of an effective cosmological constant at high…

General Relativity and Quantum Cosmology · Physics 2018-12-13 R. Myrzakulov , L. Sebastiani , S. Vagnozzi

We consider a scalar-tensor theory in teleparallel gravity where a general function of the scalar field, f(phi), is non-minimally coupled to the torsion scalar T. First, we derive the field equations in this framework. Then, we study the…

General Relativity and Quantum Cosmology · Physics 2025-07-15 Naser Mohammadipour

This work deals with $F(T)$ gravity models driven by real scalar fields with usual and phantom dynamics. We illustrate the results with examples of current interest, and we find some analytical solutions for scale factors and scalar fields.…

General Relativity and Quantum Cosmology · Physics 2010-06-22 K. K. Yerzhanov , Sh. R. Myrzakul , I. I. Kulnazarov , R. Myrzakulov

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…

General Relativity and Quantum Cosmology · Physics 2019-11-11 G. Ribeiro , R. Sfair , P. H. R. S. Moraes , J. R. L. Santos , A. de Souza Dutra

The mechanism of the initial inflationary scenario of the universe and of its late-time acceleration can be described by assuming the existence of some gravitationally coupled scalar fields $\phi $, with the inflaton field generating…

General Relativity and Quantum Cosmology · Physics 2014-02-27 Tiberiu Harko , Francisco S. N. Lobo , M. K. Mak

Using an approach that treats the Ricci scalar itself as a degree of freedom, we analyze the cosmological evolution within an f(R) model that has been proposed recently (exponential gravity) and that can be viable for explaining the…

General Relativity and Quantum Cosmology · Physics 2012-11-02 Luisa Jaime , Marcelo Salgado , Leonardo Patino

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

This study investigates the cosmological dynamics of an accelerating universe within the framework of teleparallel gravity using an exponential f(T) functional form. To obtain exact cosmological solutions, a hybrid scale factor is employed…

General Relativity and Quantum Cosmology · Physics 2026-05-27 Rajalakshmi Jena , Vishal M C , Sankarsan Tarai

We have explored a transitioning cosmic model, depicting late-time accelerated expansion in $f(R,T^{\phi})$ theory of gravity for an isotropic and homogeneous universe, where the trace of energy-momentum tensor $T^{\phi}$ is the function of…

General Relativity and Quantum Cosmology · Physics 2024-03-29 Bhojraj Singh Jayas , Vinod Kumar Bhardwaj

Scalar-tensor gravitational theories are important extensions of standard general relativity, which can explain both the initial inflationary evolution, as well as the late accelerating expansion of the Universe. In the present paper we…

General Relativity and Quantum Cosmology · Physics 2017-06-28 J. A. Belinchón , T. Harko , M. K. Mak

The homogeneous and isotropic cosmological model in generalized $ f(R,T^\phi) $ theories associated with scalar field is discussed, which is motivated by the $ f(R,T) $ theory of gravity studied by Harko et al. \cite{Harko:2011kv,…

General Relativity and Quantum Cosmology · Physics 2022-12-27 J. K. Singh , Akanksha Singh , Shaily , J. Jena

In present paper, we search the existence of dark energy scalar field models within in $f(R, T)$ gravity theory established by Harko et al. (Phys. Rev. D 84, 024020, 2011) in a flat FRW universe. The correspondence between scalar field…

General Relativity and Quantum Cosmology · Physics 2021-09-08 Vinod Kumar Bhardwaj , Anirudh Pradhan

A weakly coupled scalar field $\Phi$ with a simple exponential potential $V=M_P^4\exp(-\lambda\Phi/M_P)$ where $M_P$ is the reduced Planck mass, and $\lambda > 2$, has an attractor solution in a radiation or matter dominated universe in…

Astrophysics · Physics 2011-05-05 Pedro G. Ferreira , Michael Joyce

It is investigated the cosmological dynamics of scalar-torsion $f(T,\phi)$ gravity as a dark energy model, where $T$ is the torsion scalar of teleparallel gravity and $\phi$ is a canonical scalar field. In this context, we are concerned…

General Relativity and Quantum Cosmology · Physics 2021-06-16 Manuel Gonzalez-Espinoza , Giovanni Otalora

In this article, we explore the comprehensive narrative of cosmic evolution within a cosmological framework by utilizing a novel form of gravity known as generalized symmetric teleparallel gravity, denoted as $f(Q,T)$ gravity. Here, $Q$…

General Physics · Physics 2024-09-10 Surajit Das , Sanjay Mandal

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…

General Relativity and Quantum Cosmology · Physics 2019-06-04 P. H. R. S. Moraes , P. K. Sahoo , G. Ribeiro , R. A. C. Correa

Since viable $f(R)$ gravity models must reconcile early-universe inflation with late-time acceleration, we specifically study the dynamical behavior of such a theory during the matter-dominated to dark-energy-dominated transition epoch. By…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-03 Siqi He , Weiqiang Yang , Hangyi Jin

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…

General Relativity and Quantum Cosmology · Physics 2023-08-10 Vinod Kumar Bhardwaj , Priyanka Garg

Currently, in order to explain the accelerated expansion phase of the universe, several alternative approaches have been proposed, among which the most common are dark energy models and alternative theories of gravity. Although these…

General Relativity and Quantum Cosmology · Physics 2021-08-24 I. S. Farias , P. H. R. S. Moraes

In this paper, we have explored the field equations of f(T, B) gravity as an extension of teleparallel gravity in an isotropic and homogeneous space time. In the basic formalism developed, the dynamical parameters are derived by…

General Relativity and Quantum Cosmology · Physics 2024-09-27 S. A. Kadam , Jackson Levi Said , B. Mishra
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