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Related papers: Cosmological evolution in $f(T,B)$ gravity

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We investigate in detail the implications of the constant-roll condition on the inflationary era of a scalar field coupled to a teleparallel $f(T)$ gravity. The resulting cosmological equations constitute a reconstruction technique which…

General Relativity and Quantum Cosmology · Physics 2018-07-17 A. Awad , W. El Hanafy , G. G. L. Nashed , S. D. Odintsov , V. K. Oikonomou

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…

General Relativity and Quantum Cosmology · Physics 2022-03-15 Tiago B. Gonçalves , João Luís Rosa , Francisco S. N. Lobo

In present paper we propose further modification of $f(R,T)$-gravity (where $T$ is trace of energy-momentum tensor) by introducing higher derivatives matter fields. We discuss stability conditions in proposed theory and find restrictions…

General Relativity and Quantum Cosmology · Physics 2018-11-07 Petr V. Tretyakov

We study flat Friedmann-Lemaitre-Robertson-Walker cosmological models for a scalar field coupled nonminimally to teleparallel gravity with generic coupling and potential functions. The goal of this paper is to determine the conditions under…

General Relativity and Quantum Cosmology · Physics 2016-08-08 Laur Jarv , Alexey Toporensky

In this paper we present the equations of the evolution of the universe in $D$ spatial dimensions, as a generalization of the work of Lima \citep{lima}. We discuss the Friedmann-Robertson-Walker cosmological equations in $D$ spatial…

General Relativity and Quantum Cosmology · Physics 2012-07-09 R. F. L. Holanda , S. H. Pereira

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…

General Relativity and Quantum Cosmology · Physics 2017-06-22 M. Sharif , Ayesha Ikram

In this article, we investigate scalar field cosmology in the coincident $f(Q)$ gravity formalism. We calculate the motion equations of $f(Q)$ gravity under the flat Friedmann-Lema\^{i}tre-Robertson-Walker background in the presence of a…

General Relativity and Quantum Cosmology · Physics 2024-04-12 Sayantan Ghosh , Raja Solanki , P. K. Sahoo

We investigate isotropic and homogeneous cosmological scenarios in the scalar-tensor theory of gravity with non-minimal derivative coupling of a scalar field to the curvature given by the term $(\zeta/H_0^2) G^{\mu\nu}\nabla_\mu\phi…

General Relativity and Quantum Cosmology · Physics 2023-06-02 Sergey V. Sushkov , Rafkat Galeev

We investigate the cosmological perturbations in f(T) gravity. Examining the pure gravitational perturbations in the scalar sector using a diagonal vierbien, we extract the corresponding dispersion relation, which provides a constraint on…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-02 Shih-Hung Chen , James B. Dent , Sourish Dutta , Emmanuel N. Saridakis

$f(Q,T)$ theory of gravity is very recently proposed to incorporate within the action Lagrangian, the trace $T$ of the energy-momentum tensor along with the non-metricity scalar $Q$. The cosmological application of this theory in a…

General Relativity and Quantum Cosmology · Physics 2023-05-24 Tee-How Loo , M. Koussour , Avik De

A novel function for modified gravity is proposed, $f(R, T)=R+\lambda R^2+2\beta\ln(T)$, with constants $\lambda$ and $\beta$, scalar curvature $R$, and the trace of stress energy tensor $T$, satisfying $T=\rho-3p>0$. Subsequently, two…

General Physics · Physics 2020-06-16 Emilio Elizalde , Nisha Godani , Gauranga C. Samanta

We study the cosmological implications of gravity models which break diffeomorphisms (Diff) invariance down to transverse diffeomorphisms (TDiff). We start from the most general gravitational action involving up to quadratic terms in…

General Relativity and Quantum Cosmology · Physics 2024-02-02 Antonio G. Bello-Morales , Antonio L. Maroto

The cosmological models based on teleparallel gravity with nonzero torsion are considered. To investigate the evolution of this theory, we consider the phase-space analysis of the $f(T)$ theory. It shows when the tension scalar can be…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Yi Zhang , Hui Li , Yungui Gong , Zong-Hong Zhu

We use dynamical system methods to explore the general behaviour of $f(T)$ cosmology. In contrast to the standard applications of dynamical analysis, we present a way to transform the equations into a one-dimensional autonomous system,…

General Relativity and Quantum Cosmology · Physics 2018-03-14 A. Awad , W. El Hanafy , G. G. L. Nashed , Emmanuel N. Saridakis

In this paper, we investigate the effects of Type IV singularity through $f(T)$ gravity description of inflationary universe, where $T$ denotes the torsion scalar. With the Friedmann equations of the theory, we reconstruct a $f(T)$ model…

General Relativity and Quantum Cosmology · Physics 2019-05-03 H. F. Abadji , M. G. Ganiou , M. J. S. Houndjo , J. Tossa

We discuss cosmology based on a Cuscuta-Galileon gravity theory, which preserves just two degrees of freedom. Although there exists no additional degrees of freedom, introduction of a potential of a scalar field changes the dynamics. The…

General Relativity and Quantum Cosmology · Physics 2022-05-17 Kei-ichi Maeda , Sirachak Panpanich

We study teleparallel gravitational theories with are invariant under the conformal transformations. Wide family of the gravitational Lagrangians that are invariant under conformal transformations have investigated. Cosmological solutions…

General Relativity and Quantum Cosmology · Physics 2014-06-24 Davood Momeni , Ratbay Myrzakulov

We investigate exact and analytic solutions in $f\left( T\right) $ gravity within the context of a Friedmann--Lema\^{\i}tre--Robertson--Walker background space with nonzero spatial curvature. For the power law theory $f\left( T\right)…

General Relativity and Quantum Cosmology · Physics 2022-01-05 Andronikos Paliathanasis

We use a dynamical system approach to study the cosmological viability of $f(R,\mathcal{G})$ gravity theories. The method consists of formulating the evolution equations as an autonomous system of ODEs, using suitable variables. The…

General Relativity and Quantum Cosmology · Physics 2018-03-12 Simony Santos da Costa , Fernando V. Roig , Jailson S. Alcaniz , Salvatore Capozziello , Mariafelicia de Laurentis , Micol Benetti

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…

General Relativity and Quantum Cosmology · Physics 2018-09-18 P. K. Sahoo , P. H. R. S. Moraes , Parbati Sahoo , Binaya K. Bishi
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