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Related papers: Dynamical analysis of nonminimal coupled theories

200 papers

Static and dynamical properties of weakly coupled antiferromagnetic spin chains are treated using a mean--field approximation for the interchain coupling and exact results for the resulting effective one--dimensional problem. Results for…

Condensed Matter · Physics 2009-10-28 H. J. Schulz

Recently, in the context of $f(R)$ modified theories of gravity, a new type of model has been proposed where one directly couples the scalar curvature to matter. As any model in $f(R)$ theory, there are certain conditions which have to be…

General Relativity and Quantum Cosmology · Physics 2015-05-13 Orfeu Bertolami , Miguel Carvalho Sequeira

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

Two $F(R)$ gravity models are tested on the basis of their viability during all stages of cosmological evolution. It is shown that these models can describe both the early-time inflationary epoch and the dark energy epoch. The models are…

General Relativity and Quantum Cosmology · Physics 2026-02-10 S. D. Odintsov , V. K. Oikonomou , G. S. Sharov

We perform a phase space analysis of a non-minimally coupled modified gravity theory with the Lagrangian density of the form $\frac{1}{2} f_{1}(R)+[1+\lambda f_{2}(R)]{{\cal{L}}_{m}}$, where $f_1(R)$ and $f_2(R)$ are arbitrary functions of…

General Relativity and Quantum Cosmology · Physics 2014-06-03 Tahereh Azizi , Emad Yaraie

In this paper, we examine dynamical friction at galactic scales within the framework of coupled dark energy. This model posits dark energy as coupled quintessence, which maintains a minimal coupling to gravity but interacts non-minimally…

Astrophysics of Galaxies · Physics 2025-02-18 Nasrin Nari , Mahmood Roshan

A novel strategy is proposed for the coupling of field and circuit equations when modeling power devices in the low-frequency regime. The resulting systems of differential-algebraic equations have a particular geometric structure which…

Numerical Analysis · Mathematics 2024-04-25 Herbert Egger , Idoia Cortes Garcia , Vsevolod Shashkov , Michael Wiesheu

Coupled dark matter-dark energy systems can suffer from non-adiabatic instabilities at early times and large scales. In these proceedings, we consider two parameterizations of the dark sector interaction. In the first one the…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 L. Lopez Honorez , 0. Mena

We examine the scenario of non-minimally coupled relativistic fluid and $k$-essence scalar field in a flat Friedmann-Lemaitre-Robertson-Walker universe. By adding a non-minimal coupling term in the Lagrangian level, we study the variation…

General Relativity and Quantum Cosmology · Physics 2024-07-23 Anirban Chatterjee , Saddam Hussain , Kaushik Bhattacharya

Working notes on setting up approximate dynamical systems and nonlinear eigenvalue problems, here embedded within the theory of complex nonlinear dynamics. Computations parallel those of linear quantum theory except that we use functional…

Dynamical Systems · Mathematics 2013-12-24 K. R. W. Jones

We develop a simple method of dark energy reconstruction using a geometrical form of the luminosity-distance relation. In this method the FRW dynamical system with dark energy is reconstructed instead of the equation of state parameter. We…

Astrophysics · Physics 2017-09-29 Marek Szydlowski , Aleksandra Kurek

The self-energy-functional approach (SFA) is discussed in the context of different variational principles for strongly correlated electron systems. Formal analogies between static and dynamical variational approaches, different types of…

Strongly Correlated Electrons · Physics 2015-06-25 Michael Potthoff

We explore an autonomous system analysis of dark energy models with interactions between dark energy and cold dark matter in a general systematic approach to cosmological fluids. We investigate two types of models such as local and…

General Relativity and Quantum Cosmology · Physics 2024-03-14 Parth Shah , Gauranga C. Samanta , Kazuharu Bamba , R. Myrzakulov

The LCDM model has been presented with a number of cosmic tensions in the face of precision cosmological data, suggesting the presence of a dynamical dark energy component. In this context, we investigate the cosmology arising from a…

General Relativity and Quantum Cosmology · Physics 2026-05-08 Matthew Debono , Jackson Levi Said , Gabriel Farrugia

In this work we shall investigate the occurrence of future cosmological finite-time singularities in the dynamical system corresponding to two cosmological theories, namely that of vacuum $f(R)$ gravity and that of three fluids. The vacuum…

General Relativity and Quantum Cosmology · Physics 2018-08-01 S. D. Odintsov , V. K. Oikonomou

In this work we present a new scheme to study the tachyon dark energy model using dynamical systems analysis by considering parametrization of the equation of state(EoS) of the dark energy. Both the canonical and phantom field dynamics are…

General Relativity and Quantum Cosmology · Physics 2023-03-21 Saddam Hussain , Saikat Chakraborty , Nandan Roy , Kaushik Bhattacharya

Non-minimally coupled scalar field models suffer of unstable growing modes at the linear perturbation level. The nature of these instabilities depends on the dynamical state of the scalar field. In particular in systems which admit…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-15 Pier Stefano Corasaniti

Dynamical systems techniques are a powerful tool to analyse systems of ordinary differential equations, written in an appropriate form. For a given theory of gravity, the cosmological field equations typically lead to a system of ordinary…

General Relativity and Quantum Cosmology · Physics 2026-05-13 Christian G. Boehmer , Antonio d'Alfonso del Sordo

Cosmological models can be studied effectively using dynamical systems techniques. Starting from Brown's formulation of the variational principle for relativistic fluids, we introduce new types of couplings involving a perfect fluid, a…

General Relativity and Quantum Cosmology · Physics 2024-09-13 Christian G. Boehmer , Antonio d'Alfonso del Sordo

We propose the simplest model of teleparallel dark energy with purely a non-minimal coupling to gravity but no self-potential, a single model possessing various interesting features: simplicity, self-potential-free, the guaranteed late-time…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Je-An Gu , Chung-Chi Lee , Chao-Qiang Geng