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Related papers: Friedmann-like universes with weak torsion: a dyna…

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We consider spatially homogeneous and isotropic cosmologies with non-zero torsion. Given the high symmetry of these universes, we adopt a specific form for the torsion tensor that preserves the homogeneity and isotropy of the spatial…

General Relativity and Quantum Cosmology · Physics 2019-05-01 D. Kranas , C. G. Tsagas , J. D. Barrow , D. Iosifidis

We study the stable behaviour of discrete dynamical systems where the map is convex and monotone with respect to the standard positive cone. The notion of tangential stability for fixed points and periodic points is introduced, which is…

Dynamical Systems · Mathematics 2011-06-20 Marianne Akian , Stephane Gaubert , Bas Lemmens

Cosmological approaches of autonomous dynamical system in the framework of $f(T)$ gravity are investigated in this paper. Our methods applied to flat Friedmann-Robertson-Walker equations in $f(T)$ gravity, consist to extract dynamical…

General Relativity and Quantum Cosmology · Physics 2018-05-02 M. G. Ganiou , P. H. Logbo , M. J. S. Houndjo , J. Tossa

We study the phase space dynamics of cosmological models in the theoretical formulations of non-minimal metric-torsion couplings with a scalar field, and investigate in particular the critical points which yield stable solutions exhibiting…

General Relativity and Quantum Cosmology · Physics 2017-08-18 Arshdeep Singh Bhatia , Sourav Sur

We consider the kinematical and dynamical evolution of Friedmann universes with a mixture of non-interacting matter and a ghost-like field, in a scenario analogous to that advocated by the Quintom model. Assuming that the conventional…

General Relativity and Quantum Cosmology · Physics 2020-10-28 Ameya Chavda , John D. Barrow , Christos G. Tsagas

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

This paper analyzes the stability of the closed Einstein static universe by using linear homogeneous perturbations in the framework of energy-momentum squared gravity. This newly developed proposal resolves the primordial singularity and…

General Relativity and Quantum Cosmology · Physics 2021-08-25 M. Sharif , M. Zeeshan Gul

One of the possible extensions of Einstein's General Theory of Relativity consists in allowing for the presence of spacetime torsion. The form of the underlying torsion tensor can be chosen such that the homogeneity and isotropy of…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-20 C. M. J. Marques , C. J. A. P. Martins

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

In this work, we have carried on dynamical system analysis of hessence field coupling with dark matter in $f(T)$ gravity. We have analysed the critical points due to autonomous system. The resulting autonomous system is non-linear. So, we…

General Relativity and Quantum Cosmology · Physics 2017-07-20 Jyotirmay Das Mandal , Ujjal Debnath

This is an expository paper on Lyapunov stability of equilibria of autonomous Hamiltonian systems. Our aim is to clarify the concept of weak instability, namely instability without non-constant motions which have the equilibrium as limit…

Dynamical Systems · Mathematics 2012-10-05 Gaetano Zampieri

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 show that the inclusion of simple anisotropic pressures stops the isotropic Friedmann universe being a stable attractor as an initial or final singularity is approached when pressures can exceed the energy density. This shows that the…

General Relativity and Quantum Cosmology · Physics 2014-11-20 John D Barrow , Kei Yamamoto

In a previous paper [arXiv:1308.1852] we showed how a finite system of discrete particles interacting with each other via Newtonian gravitational attraction would lead to precisely the same dynamical equations for homothetic motion as in…

General Relativity and Quantum Cosmology · Physics 2015-06-22 George F. R. Ellis , Gary W. Gibbons

In this work, we perform a detailed dynamical analysis for the cosmological applications of a nonminimal torsion-matter coupled gravity. Two alternative formalisms are proposed, which enable one to choose between the easier approach for a…

General Relativity and Quantum Cosmology · Physics 2016-01-20 Sante Carloni , Francisco S. N. Lobo , Giovanni Otalora , Emmanuel N. Saridakis

On the basis of qualitative theory of differential equations it is shown that dynamic system based on the system of Einstein - Klein - Gordon equations with regard to Friedman Universe has a stable center corresponding to zero values of…

General Relativity and Quantum Cosmology · Physics 2016-09-06 Yurii Ignat'ev

We apply a very simple procedure to construct non-singular cosmological models for flat Friedmann universes filled with minimally coupled scalar fields or by tachyon Born-Infeld-type fields. Remarkably, for the minimally coupled scalar…

General Relativity and Quantum Cosmology · Physics 2024-03-14 Alexander Kamenshchik , Polina Petriakova

Methods of dynamical systems have been used to study homogeneous and isotropic cosmological models with a varying speed of light (VSL). We propose two methods of reduction of dynamics to the form of planar Hamiltonian dynamical systems for…

General Relativity and Quantum Cosmology · Physics 2008-07-22 Marek Szydlowski , Adam Krawiec

In this paper, we study the phase space of cosmological models in the context of Einstein-Gauss-Bonnet theory. More specifically, we consider a generalized dynamical system that encapsulates the main features of the theory and for the cases…

General Relativity and Quantum Cosmology · Physics 2020-07-15 N. Chatzarakis , V. K. Oikonomou

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
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