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Related papers: Homogeneous cosmologies in generalized modified gr…

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A brief introduction on the issue of stability in generalized modified gravity is presented and the dynamical system methods are used in the investigation of the stability of spatially flat homogeneous cosmologies within a large class of…

General Relativity and Quantum Cosmology · Physics 2008-11-18 Guido Cognola , Sergio Zerbini

Modified gravity theories can be used for the description of homogeneous and isotropic cosmological models through the corresponding field equations. These can be cast into systems of autonomous differential equations because of their sole…

General Relativity and Quantum Cosmology · Physics 2024-04-08 Christian G. Boehmer , Erik Jensko , Ruth Lazkoz

The field equations of modified gravity theories, when considering a homogeneous and isotropic cosmological model, always become autonomous differential equations. This relies on the fact that in such models all variables only depend on…

General Relativity and Quantum Cosmology · Physics 2023-02-03 Christian G. Boehmer , Erik Jensko , Ruth Lazkoz

A number of dynamical system formulations have been proposed over the last few years to analyse cosmological solutions in $f(R)$ gravity. The aim of this article is to provide a brief introduction to the different approaches, presenting…

General Relativity and Quantum Cosmology · Physics 2022-05-06 Saikat Chakraborty , Peter K. S. Dunsby , Kelly Macdevette

Investigating the accelerated expansion of the universe with cosmography is a best method to constraint cosmological models. In this work, in the $F(G)$ modified gravity framework, we obtain equations of motion in a flat FRW metric. Then we…

General Physics · Physics 2012-06-04 M. R. Setare , N. Mohammadipour

Spatially homogeneous cosmological models with a positive cosmological constant are investigated, using dynamical systems methods. We focus on the future evolution of these models. In particular, we address the question whether there are…

General Relativity and Quantum Cosmology · Physics 2011-07-18 Martin Goliath , George F. R. Ellis

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

The so called $f(X)$ hybrid metric-Palatini gravity presents a unique viable generalisation of the $f(R)$ theories within the metric-affine formalism. Here the cosmology of the $f(X)$ theories is studied using the dynamical system approach.…

General Relativity and Quantum Cosmology · Physics 2015-09-28 Sante Carloni , Tomi Koivisto , Francisco S. N. Lobo

We propose a new dynamical system formalism for the analysis of f(R) cosmologies. The new approach eliminates the need for cumbersome inversions to close the dynamical system and allows the analysis of the phase space of f(R)-gravity models…

General Relativity and Quantum Cosmology · Physics 2015-10-27 Sante Carloni

In this thesis we investigate cosmological models more general than the isotropic and homogeneous Friedmann-Lemaitre models. We focus on cosmologies with one spatial degree of freedom, whose matter content consists of a perfect fluid and…

General Relativity and Quantum Cosmology · Physics 2009-09-29 Woei Chet Lim

We study cosmological evolutions of the generalized model of nonlinear massive gravity in which the graviton mass is given by a rolling scalar field and is varying along time. By performing dynamical analysis, we derive the critical points…

High Energy Physics - Theory · Physics 2015-06-12 De-Jun Wu , Yifu Cai , Yun-Song Piao

In this paper, we derive the field equations of modified Gauss-Bonnet gravity termed as $f(R,G)$ gravity for the non-flat Friedmann-Robertson-Walker (FRW) spacetime. We utilize the dynamical system approach to study the cosmic dynamics of…

General Relativity and Quantum Cosmology · Physics 2025-01-22 Ashutosh Singh

In this article, we examine the dynamical evolution of flat FRW cosmological model in $f(R, L_m)$ gravity theory. We consider the general form of $f(R, L_m)$ defined as $f(R, L_m) = \Lambda + \frac{\alpha}{2} R + \beta L_m^n$, where…

General Relativity and Quantum Cosmology · Physics 2025-02-14 Aman Shukla , Rakesh Raushan , Raghavendra Chaubey

We consider static cosmological solutions along with their stability properties in the framework of a recently proposed theory of massive gravity. We show that the modifcation introduced in the cosmological equations leads to several new…

General Relativity and Quantum Cosmology · Physics 2012-07-27 Luca Parisi , Ninfa Radicella , Gaetano Vilasi

The Nobel Prize winning confirmation in 1998 of the accelerated expansion of our Universe put into sharp focus the need of a consistent theoretical model to explain the origin of this acceleration. As a result over the past two decades…

General Relativity and Quantum Cosmology · Physics 2018-12-07 Sebastian Bahamonde , Christian G. Boehmer , Sante Carloni , Edmund J. Copeland , Wei Fang , Nicola Tamanini

We discuss dynamical systems approaches and methods applied to flat Robertson-Walker models in $f(R)$-gravity. We argue that a complete description of the solution space of a model requires a global state space analysis that motivates…

General Relativity and Quantum Cosmology · Physics 2016-09-07 Artur Alho , Sante Carloni , Claes Uggla

We consider f(R) modified gravity theories for describing varying speed of light in a spatially flat FRW model, and find some exact solutions. Also we examine the dynamics of this model by dynamical system method assuming a LambdaCDM…

General Relativity and Quantum Cosmology · Physics 2010-02-02 Azam Izadi , Ali Shojai

We study the dynamics of homogeneous and isotropic Friedmann-Lema\^itre-Robertson-Walker cosmological models with positive spatial curvature within the context of mimetic gravity theory by employing dynamical system techniques. Our analysis…

General Relativity and Quantum Cosmology · Physics 2024-09-18 Alberto Fritis , Daniel Villalobos-Silva , Yerko Vásquez , Carlos H. López-Caraballo , Juan Carlos Helo

We study the evolution of homogeneous and isotropic, flat cosmological models within the general scalar-tensor theory of gravity with arbitrary coupling function and potential and scrutinize its limit to general relativity. Using the…

General Relativity and Quantum Cosmology · Physics 2009-04-24 Piret Kuusk , Laur Jarv , Margus Saal

The stability criteria for spatially flat homogeneous and isotropic cosmological dynamical system is investigated with the interaction of a scalar field endowed with a perfect fluid.In this paper, we depict the dynamical system perspective…

General Relativity and Quantum Cosmology · Physics 2021-01-25 S. Surendra Singh , Chingtham Sonia
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