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Related papers: A note on the dynamical system formulations in $f(…

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We investigate the cosmological implications of a new class of modified gravity, where the field equations generically include higher-order derivatives of the matter fields, arising from the introduction of non-dynamical auxiliary fields in…

General Relativity and Quantum Cosmology · Physics 2016-07-01 Tiberiu Harko , Francisco S. N. Lobo , Emmanuel N. Saridakis

We study the evolution of the physical variables in $f\left( Q\right) $-gravity for two families of symmetric and flat connections in a spatially flat Friedmann--Lema\^{\i}tre--Robertson--Walker geometry where the equation of motion for the…

General Relativity and Quantum Cosmology · Physics 2023-05-16 Andronikos Paliathanasis

This is a brief review of the standard model of cosmology. We first introduce the FRW models and their flat solutions for energy fluids playing an important role in the dynamics at different epochs. We then introduce different cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-15 Jorge L. Cervantes-Cota , George Smoot

In this paper we present a cosmological model arising from a non-conservative gravitational theory proposed in [PRD 95, 101501(R) (2017)]. The novel feature where comparing with previous implementations of dissipative effects in gravity is…

General Relativity and Quantum Cosmology · Physics 2018-05-28 Júlio C. Fabris , Hermano Velten , Thiago R. P. Caramês , Matheus J. Lazo , Gastão S. F. Frederico

In this work we explore the dynamical system phase space of Einstein-Gauss-Bonnet theory in the cosmological minisuperspace. This approach binds the main features of the theory through a system of autonomous differential equations, in the…

General Relativity and Quantum Cosmology · Physics 2022-11-14 Konstantinos F. Dialektopoulos , Jackson Levi Said , Zinovia Oikonomopoulou

This study systematically investigates the cosmological dynamics of two well-motivated functional forms in $f(T,B)$ gravity within a flat Friedmann-Lema\^{i}tre-Robertson-Walker (FLRW) universe. Here $T$ denotes the torsion scalar and $B$…

General Relativity and Quantum Cosmology · Physics 2026-02-16 Jianwen Liu , Fabao Gao , Aqeela Razzaq

The basic aim of this manuscript is to investigate the cosmological solutions in the context of the modified $f(R, T)$ theory of gravity, where $R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor. For our current…

General Relativity and Quantum Cosmology · Physics 2024-03-26 Adnan Malik , Tayyaba Naz , Aimen Rauf , M. Farasat Shamir , Z. Yousaf

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

This thesis employs the dynamical systems approach to explore two cosmological models: an anisotropic dark energy scenario in a Bianchi-I background and the Generalized SU(2) Proca (GSU2P) theory in a flat FLRW background. In the first…

General Relativity and Quantum Cosmology · Physics 2025-06-23 Santiago García-Serna

Several extensions of General Relativity and high energy physics include scalar fields as extra degrees of freedom. In the search for predictions in the non-linear regime of cosmological evolution, the community makes use of numerical…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-04 Claudio Llinares , David Mota

A multidimensional cosmology with FRW type metric having 4-dimensional space-time and $d$-dimensional Ricci-flat internal space is considered with a higher dimensional cosmological constant. The classical cosmology in commutative and…

General Relativity and Quantum Cosmology · Physics 2013-04-25 K. Zeynali , F. Darabi , H. Motavalli

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

In this paper, we perform the dynamical system analysis of the cosmological models framed in the extended teleparallel gravity, the $f (T, B)$ gravity. We use the mapping, $f(T, B)$ $\rightarrow$-$T$+$\tilde{f}(T, B)$, and define the…

General Relativity and Quantum Cosmology · Physics 2023-09-13 S. A. Kadam , Ninaad P. Thakkar , B. Mishra

We study the geometry of the phase space of spatially flat Friedmann-Lemaitre-Robertson-Walker models in f(R) gravity, for a general form of the function f(R). The equilibrium points (de Sitter spaces) and their stability are discussed, and…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Jose C. C. de Souza , Valerio Faraoni

We discuss recent results on the cosmology of extended theories of gravity formulated in the Palatini approach, i.e., assuming that metric and connection are independent fields. In particular, we focus on the attempts to explain the cosmic…

General Relativity and Quantum Cosmology · Physics 2012-07-23 Gonzalo J. Olmo

The cosmological reconstruction scheme for modified $F(R)$ gravity is developed in terms of e-folding (or, redshift). It is demonstrated how any FRW cosmology may emerge from specific $F(R)$ theory. The specific examples of well-known…

High Energy Physics - Theory · Physics 2014-11-20 Shin'ichi Nojiri , Sergei D. Odintsov , Diego Saez-Gomez

In this work, we systematically present a new dynamical systems approach to standard inflationary processes and their variants as constant-roll inflation. Using the techniques presented in our work one can in general investigate the…

General Relativity and Quantum Cosmology · Physics 2026-01-13 Sandip Biswas , Saddam Hussain , Kaushik Bhattacharya

We present a set of equations describing the evolution of the scalar-type cosmological perturbation in a gravity with general quadratic order curvature coupling terms. Equations are presented in a gauge ready form, thus are ready to…

General Relativity and Quantum Cosmology · Physics 2011-08-17 H. Noh , J. Hwang

Dynamical system techniques are extremely useful to study cosmology. It turns out that in most of the cases, we deal with finite isolated fixed points corresponding to a given cosmological epoch. However, it is equally important to analyse…

General Relativity and Quantum Cosmology · Physics 2017-03-22 Mariam Bouhmadi-López , João Marto , João Morais , César M. Silva

This is a brief review of modified gravity cosmologies. Generically extensions of gravity action involve higher derivative terms, which can result in ghosts and instabilities. There are three ways to circumvent this: Chern-Simons terms,…

General Relativity and Quantum Cosmology · Physics 2010-02-24 Tomi S. Koivisto
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