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In this paper we study the dynamics of {\it orthogonal spatially homogeneous} Bianchi cosmologies in $R^n$-gravity. We construct a compact state space by dividing the state space into different sectors. We perform a detailed analysis of the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Naureen Goheer , Jannie A. Leach , Peter K. S. Dunsby

The study addresses matter-coupled modified gravity, particularly $f (T, \mathcal{T})$ gravity, unveiling distinct formalism. The research further discusses stability analysis, and the dynamical system approach, exploring the dynamics of…

General Relativity and Quantum Cosmology · Physics 2023-12-22 L. K. Duchaniya , Santosh V Lohakare , B. Mishra

We present the first formulation of the recently proposed $f(R,\mathcal{L}_m,T)$ theory of gravity within the Palatini formalism, a well-known alternative variational approach where the metric and connection are treated as independent…

General Relativity and Quantum Cosmology · Physics 2024-11-26 J. G. de Lima Júnior , P. H. R. S. Moraes , E. Brito , J. A. S. Fortunato

The utmost concern of this article is the construction of modified scalar functions (structure scalars) by taking Palatini $f(R)$ gravitational theory into account. At first, a general formalism is established in which we assess…

General Relativity and Quantum Cosmology · Physics 2021-09-02 M. Z. Bhatti , Z. Yousaf , Z. Tariq

A complete analysis of the dynamics of the Hu-Sawicki modification to General Relativity is presented. In particular, the full phase-space is given for the case in which the model parameters are taken to be n=1, c1=1, and several stable de…

General Relativity and Quantum Cosmology · Physics 2015-11-03 Sulona Kandhai , Peter K. S. Dunsby

A novel idea that the cosmic acceleration can be understood from the perspective that spacetime dynamics is an emergent phenomena was proposed by T. Padmanabhan. The Friedmann equations of FRW universe can be derived from different gravity…

General Relativity and Quantum Cosmology · Physics 2014-03-04 Wen-Yuan Ai , Xian-Ru Hu , Hua Chen , Jian-Bo Deng

We investigate the qualitative evolution of (D+1)-dimensional cosmological models in f(R) gravity for the general case of the function f(R). The analysis is specified for various examples, including the (D+1)-dimensional generalization of…

General Relativity and Quantum Cosmology · Physics 2016-02-03 R. M. Avagyan , E. V. Chubaryan , G. H. Harutyunyan , A. A. Saharian

We consider a class of metric f(R) modified gravity theories, analyze them in the context of a Friedmann-Robertson-Walker cosmology and confront the results with some of the known constraints imposed by observations. In particular, we focus…

General Relativity and Quantum Cosmology · Physics 2012-06-11 Luisa G. Jaime , Leonardo Patino , Marcelo Salgado

Two approaches to the study of cosmological density perturbations in modified theories of Palatini gravity have recently been discussed. These utilise, respectively, a generalisation of Birkhoff's theorem and a direct linearization of the…

General Relativity and Quantum Cosmology · Physics 2010-10-27 Kotub Uddin , James E Lidsey , Reza Tavakol

The primary aim of this work is to explore feasible bouncing cosmological solutions in the framework of $f(\mathcal{Q}, \mathcal{C})$ gravity, where $\mathcal{Q}$ denotes non-metricity and $\mathcal{C}$ indicates the boundary term. To…

General Relativity and Quantum Cosmology · Physics 2025-08-12 M. Sharif , M. Zeeshan Gul , Ahmad Nawaz

Assuming equation of state for quintessential matter: $p=w(z)\rho$, we analyse dynamical behaviour of the scale factor in FRW cosmologies. It is shown that its dynamics is formally equivalent to that of a classical particle under the action…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Marek Szydlowski , Wojciech Czaja

We study the cosmological evolution of the field equations in the context of Einstein-Aether cosmology by including a scalar field in a spatially flat Friedmann--Lema\^{\i}tre--Robertson--Walker spacetime. Our analysis is separated into two…

General Relativity and Quantum Cosmology · Physics 2020-01-17 Andronikos Paliathanasis , G. Papagiannopoulos , Spyros Basilakos , John D. Barrow

We investigate the cosmological dynamics of FHDE within $f(T)$ gravity by employing the dynamical system approach in a spatially flat FRW background. By introducing appropriate dimensionless variables, the field equations are reformulated…

General Relativity and Quantum Cosmology · Physics 2026-02-23 Elangbam Chingkheinganba Meetei , S. Surendra Singh

We consider the field equations for a flat FRW cosmological model, in a generic $f(R)$ gravity model and cast them into a, completely normalized-dimensionless, system of O.D.Es for the scale factor and the function $f(R)$, with respect to…

General Relativity and Quantum Cosmology · Physics 2018-01-24 A. Kuiroukidis

We apply the dynamical systems tools to study the (linear) dynamics of Friedmann-Robertson-Walker universes that are fuelled by non-linear electrodynamics. We focus, mainly, in two particular models. In the first model the cosmic evolution…

General Relativity and Quantum Cosmology · Physics 2009-05-08 Ricardo Garcia-Salcedo , Tame Gonzalez , Claudia Moreno , Israel Quiros

The $f(T)$ gravity is one of the extensions of teleparallel equivalent of general relativity, in which more general functions of the torsion scalar $T$ can be described. With the proposed functional form of $f(T) = \alpha T - \beta u^{-n} +…

General Relativity and Quantum Cosmology · Physics 2026-04-14 Suraj Kumar Behera , S. A. Kadam , Pratik P. Ray , B. Mishra

We explore the phase-space of a multiscalar-torsion gravitational theory within a cosmological framework characterized by a spatially flat Friedmann-Lema\^{\i}tre-Robertson-Walker model. Our investigation focuses on teleparallelism and…

General Relativity and Quantum Cosmology · Physics 2024-03-07 Genly Leon , Andronikos Paliathanasis , Alfredo D. Millano

In this paper, we carry out a study of viable cosmological models in $f(R)$-gravity at the background level. We use observable parameters like $\Omega$ and $\gamma$ to form autonomous system of equations and show that the models under…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-28 Amna Ali , Radouane Gannouji , M. Sami , Anjan A. Sen

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

We propose a Hamiltonian formalism for a generalized Friedmann-Roberson-Walker cosmology model in the presence of both a variable equation of state (EOS) parameter $w(a)$ and a variable cosmological constant $\Lambda(a)$, where $a$ is the…

High Energy Physics - Theory · Physics 2008-11-26 Jie Ren , Xin-He Meng , Liu Zhao