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

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The present work is an example of the application of the dynamical system analysis in the context of cosmology. Here cosmic evolution is considered in the background of homogeneous and isotropic flat Friedmann-Lema\^{i}tre-Robertson-Walker…

General Relativity and Quantum Cosmology · Physics 2020-11-20 Soumya Chakraborty , Sudip Mishra , Subenoy Chakraborty

We study well-posedness and long time behavior of the nonlinear Vlasov-Poisson- Fokker-Planck system with an external confining potential. The system describes the time evolution of particles (e.g.$\,\,$in a plasma) undergoing diffusion,…

Analysis of PDEs · Mathematics 2024-06-24 Gayrat Toshpulatov

We begin with a review of the statements of non-linear, linear and mode stability of autonomous dynamical systems in classical mechanics, using symplectic geometry. We then discuss what the phase space and the Hamiltonian of general…

General Relativity and Quantum Cosmology · Physics 2020-08-10 Prashant Kocherlakota , Pankaj S. Joshi

We use higher derivative classical gravity to study the nonlinear coupling between the cosmological expansion of the universe and metric oscillations of Planck frequency and very small amplitude. We derive field equations at high orders in…

High Energy Physics - Theory · Physics 2014-11-18 Bob Holdom

In this work we try to understand the late time acceleration of the universe by assuming some modification in the geometry of the space and using dynamical system analysis. This technique allows to understand the behavior of the universe…

General Relativity and Quantum Cosmology · Physics 2021-11-18 Parth Shah , Gauranga C. Samanta

The general solution of the gravitational field equations for a full causal bulk viscous stiff cosmological fluid, with bulk viscosity coefficient proportional to the energy density to the power 1/4, is obtained in the flat…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. K. Mak , T. Harko

A refined version of a recently introduced method for analysing the dynamics of an inhomogeneous irrotational dust universe is presented. A fully non-perturbative numerical computation of the time dependence of volume in this framework…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-01 Harald Skarke

We study the dynamics of a non-minimally coupled scalar field cosmology with a potential function. We use the framework of dynamical systems theory to investigate all evolutional paths admissible for all initial conditions. Additionally, we…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Orest Hrycyna , Marek Szydlowski

This paper provides a new unified framework for second-moment stability of discrete-time linear systems with stochastic dynamics. Relations of notions of second-moment stability are studied for the systems with general stochastic dynamics,…

Systems and Control · Electrical Eng. & Systems 2019-11-04 Yohei Hosoe , Tomomichi Hagiwara

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

Many nonlinear dynamical systems can be written as Lure systems, which are described by a linear time-invariant system interconnected with a diagonal static sector-bounded nonlinearity. Sufficient conditions are derived for the global…

Systems and Control · Computer Science 2015-09-07 Kwang-Ki K. Kim , Richard D. Braatz

The novel proposal to invoke the split of the Ricci scalar into bulk and boundary terms in the gravitational action, opens up a new avenue of investigation into stellar dynamics. The Lagrangian contains functional forms of the bulk term…

General Relativity and Quantum Cosmology · Physics 2026-05-14 Sudan Hansraj , Christian G. Boehmer , Ndumiso Buthelezi

We propose a cosmological model that describes isotropic expansion of inhomogeneous universe. The energy-momentum tensor that creates the spatial inhomogeneity may not affect the uniform expansion scaling factor $a(t)$ in the FLRW-like…

High Energy Physics - Theory · Physics 2014-10-15 Wei-Jian Geng , H. Lu

This paper reviews various applications of the theory of smooth dynamical systems to conceptual problems of nonequilibrium statistical mechanics. We adopt a new point of view which has emerged progressively in recent years, and which takes…

chao-dyn · Physics 2015-06-24 David Ruelle

We consider the uniqueness of equilibrium states for dynamical systems that satisfy certain weak, non-uniform versions of specification, expansivity, and the Bowen property at a fixed scale. Following Climenhaga-Thompson's approach which…

Dynamical Systems · Mathematics 2022-01-19 Maria Jose Pacifico , Fan Yang , Jiagang Yang

A new definition of continuous-time equilibrium controls is introduced. As opposed to the standard definition, which involves a derivative-type operation, the new definition parallels how a discrete-time equilibrium is defined, and allows…

Optimization and Control · Mathematics 2021-07-15 Yu-Jui Huang , Zhou Zhou

We consider piecewise linear discrete time macroeconomic models, which possess a continuum of equilibrium states. These systems are obtained by replacing rational inflation expectations with a boundedly rational, and genuinely sticky,…

Dynamical Systems · Mathematics 2017-11-22 Pavel Krejci , Harbir Lamba , Dmitrii Rachinskii

We study the well-posedness and stability of an impedance passive infinite-dimensional linear system under nonlinear feedback of the form $u(t)=\phi(v(t)-y(t))$, where $\phi$ is a monotone function. Our first main result introduces…

Optimization and Control · Mathematics 2025-06-19 Anthony Hastir , Lassi Paunonen

The paper deals with cosmological solutions describing different phases of the Universe for the homogeneous and isotropic FLRW model of the Universe with torsion. Normally, torsion field is not suitable for maximally symmetric space time…

General Relativity and Quantum Cosmology · Physics 2020-10-30 Akash Bose , Subenoy Chakraborty

It is useful to study the space of all cosmological models from a dynamical systems perspective, that is, by formulating the Einstein field equations as a dynamical system using appropriately normalized variables. We will discuss various…

General Relativity and Quantum Cosmology · Physics 2016-10-17 J. Wainwright , W. C. Lim