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Related papers: Stability in Generalized Modified Gravity

200 papers

The stability issue of generalized modified gravitational models is discussed with particular emphasis to de Sitter solutions. Two approaches are briefly presented.

General Relativity and Quantum Cosmology · Physics 2010-06-10 Guido Cognola , Lorenzo Sebastiani , Sergio Zerbini

Conditions for the existence and stability of de Sitter space in modified gravity are derived by considering inhomogeneous perturbations in a gauge-invariant formalism. The stability condition coincides with the corresponding condition for…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Valerio Faraoni , Shahn Nadeau

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

Motivated by the dark energy issue, a minisuperspace approach to the stability for modified gravitational models in a four dimensional cosmological setting are investigated. Specifically, after revisiting the $f(R)$ case, $R$ being the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Guido Cognola , Monica Gastaldi , Sergio Zerbini

Within the context of modified gravity and dark energy scenarios of the accelerating universe, we study the stability of de Sitter space with respect to inhomogeneous perturbations using a gauge-independent formalism. In modified gravity…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Valerio Faraoni

A brief review of cosmology in some generalized modified gravity theories with vacuum polarization is presented. Stability question of de Sitter solution is investigated.

General Relativity and Quantum Cosmology · Physics 2009-01-14 Petr Tretyakov

The one-loop quantisation of a general class of modified gravity models around a classical de Sitter background is presented. Application to the stability of the models is addressed.

High Energy Physics - Theory · Physics 2009-11-11 Guido Cognola , Sergio Zerbini

We consider the Einstein static and the de Sitter universe solutions and examine their instabilities in a subclass of quadratic modified theories for gravity. This modification proposed by Nash is an attempt to generalize general…

General Physics · Physics 2021-04-01 Mudhahir Al Ajmi

Modified gravity is one of the most promising candidates for explaining the current accelerating expansion of the Universe, and even its unification with the inflationary epoch. Nevertheless, the wide range of models capable to explain the…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Álvaro de la Cruz-Dombriz , Diego Sáez-Gómez

We consider general curvature-invariant modifications of the Einstein-Hilbert action that become important only in regions of extremely low space-time curvature. We investigate the far future evolution of the universe in such models,…

We obtain conditions for the existence and stability of de Sitter attractors in the phase space of spatially homogeneous and isotropic cosmology in generalized theories of gravity (including non-linear and scalar-tensor theories). These…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Valerio Faraoni

Quadratic curvature corrections to Einstein-Hilbert action lead in general to higher-order equations of motion, which can induced instability of some unperturbed solutions of General Relativity. We study conditions for stability of de…

General Relativity and Quantum Cosmology · Physics 2010-11-11 A. V. Toporensky , P. V. Tretyakov

The aim of this paper is to reconstruct and analyze the stability of some cosmological models against linear perturbations in $f(\mathcal{G},T)$ gravity ($\mathcal{G}$ and $T$ represent the Gauss-Bonnet invariant and trace of the…

General Relativity and Quantum Cosmology · Physics 2017-06-22 M. Sharif , Ayesha Ikram

We present a brief overview of the stability analysis of the Einstein static universe in various modified theories of gravity, like f(R) gravity, Gauss-Bonnet or f(G) gravity, and Horava-Lifshitz gravity.

General Relativity and Quantum Cosmology · Physics 2016-11-15 Christian G. Boehmer , Lukas Hollenstein , Francisco S. N. Lobo , Sanjeev S. Seahra

We examine in this paper the stability analysis in $f(R; T; R_{\mu\nu}T^{\mu\nu})$ modified gravity, where $R$ and $T$ are the Ricci scalar and the trace of the energy-momentum tensor, respectively. By considering the flat Friedmann…

General Relativity and Quantum Cosmology · Physics 2016-12-15 E. H. Baffou , M. J. S. Houndjo , J. Tossa

In the present work we suggest a general covariant theory which can be used to study the stability of any physical system treated geometrically. Stability conditions are connected to the magnitude of the deviation vector. This theory is a…

General Relativity and Quantum Cosmology · Physics 2016-11-15 M. I. Wanas , M. A. Bakry

Possible models of modified gravity are being extensively studied now, with most phenomenological motivations coming from puzzles and tensions in cosmology due to a natural desire to better fit the known and newly coming data. At the same…

General Relativity and Quantum Cosmology · Physics 2024-02-06 Alexey Golovnev , Maria-Jose Guzman

The stability properties of the Einstein Static solution of General Relativity are altered when corrective terms arising from modification of the underlying gravitational theory appear in the cosmological equations. In this paper the…

General Relativity and Quantum Cosmology · Physics 2014-11-21 Rosangela Canonico , Luca Parisi

We present a general approach to the analysis of gauge stability of 3+1 formulations of General Relativity (GR). Evolution of coordinate perturbations and the corresponding perturbations of lapse and shift can be described by a system of…

General Relativity and Quantum Cosmology · Physics 2009-11-07 A. M Khokhlov , I. D. Novikov

We propose a model for modified gravity that meets the conditions of viability. The model has stable constant curvature solution and for an special case contains flat space time solution. The model also leads to matter stability under small…

General Relativity and Quantum Cosmology · Physics 2015-06-22 L. N. Granda
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