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Related papers: Stability in Generalized Modified Gravity

200 papers

We consider cosmological dynamics in generalized modified gravity theory with the $R\Box R$ term added to the action of the form $R+R^N$. Influence of $R \Box R$ term to the known solutions of modified gravity is described. We show that in…

General Relativity and Quantum Cosmology · Physics 2011-06-10 M. Skugoreva , A. Toporensky , P. Tretyakov

The effect of de Sitter transformations on Tsamis and Woodard's solutions to the linearized gauge fixed equations of motion of quantum gravity in a de Sitter space background is worked out explicitly. It is shown that these solutions are…

High Energy Physics - Theory · Physics 2007-05-23 Gary Kleppe

Viable models of modified gravity which satisfy both local as well as cosmological tests are investigated. It is demonstrated that some versions of such highly non-linear models exhibit multiply de Sitter universe solutions, which often…

General Relativity and Quantum Cosmology · Physics 2009-02-20 G. Cognola , E. Elizalde , S. D. Odintsov , P. Tretyakov , S. Zerbini

De Sitter solutions play an important role in cosmology because the knowledge of unstable de Sitter solutions can be useful to describe inflation, whereas stable de Sitter solutions are often used in models of late-time acceleration of the…

General Relativity and Quantum Cosmology · Physics 2021-05-18 Sergey Vernov , Ekaterina Pozdeeva

This article deals with different generalizations of the discrete stability property. Three possible definitions of discrete stability are introduced, followed by a study of some particular cases of discrete stable distributions and their…

Probability · Mathematics 2015-02-10 Lenka Slámová , Lev B. Klebanov

In the framework of the recently proposed models of massive gravity, defined with respect to a de Sitter reference metric, we obtain new homogeneous and isotropic solutions for arbitrary cosmological matter and arbitrary spatial curvature.…

High Energy Physics - Theory · Physics 2015-06-05 David Langlois , Atsushi Naruko

We consider the model of modified gravity with dynamical torsion. This model was found to have promising stability properties about various backgrounds. The model admits a self-accelerating solution. We have shown previously that if the…

High Energy Physics - Theory · Physics 2018-03-28 V. Nikiforova

We investigate the scalar field dynamics of models with nonminimally coupled scalar fields in the presence of the Gauss-Bonnet term and derive the structure of the effective potential and conditions for stable de Sitter solutions in…

General Relativity and Quantum Cosmology · Physics 2019-10-21 Ekaterina O. Pozdeeva , Mohammad Sami , Alexey V. Toporensky , Sergey Yu. Vernov

Gravitational instability in classical Jeans theory, General Relativity, and modified gravity is considered. The background density increase leads to a faster growth of perturbations in comparison with the standard theory. The transition to…

General Relativity and Quantum Cosmology · Physics 2015-06-22 E. V. Arbuzova , A. D. Dolgov , L. Reverberi

The existence of anisotropic stress of a purely geometrical origin seems to be a characteristic of higher order gravity models, and has been suggested as a probe to test these models observationally, for example in weak lensing experiments.…

General Relativity and Quantum Cosmology · Physics 2011-05-10 Ippocratis D. Saltas , Martin Kunz

Modified theories of gravity usually present new degrees of freedom, as well as higher order derivatives, wrong signs in certain terms and complicated couplings already present in the Lagrangian from the beginning or originated by the field…

General Relativity and Quantum Cosmology · Physics 2022-07-28 Adrià Delhom , Alejandro Jiménez-Cano , Francisco José Maldonado Torralba

Dynamical system methods are used in the study of the stability of spatially flat homogeneous cosmologies within a large class of generalized modified gravity models in the presence of a relativistic matter-radiation fluid. The present…

High Energy Physics - Theory · Physics 2008-12-18 Guido Cognola , Sergio Zerbini

In the context of $f(R)$ gravity theories, the issue of finding static and spherically symmetric black hole solutions is addressed. Two approaches to study the existence of such solutions are considered: first, constant curvature solutions,…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Alvaro de la Cruz-Dombriz , Antonio Dobado , Antonio L. Maroto

We discuss the moduli stabilization in a de Sitter compactification model obtained coupling D-dimensional gravity to scalar and gauge fields. This class of models is characterized by two moduli: one related to the volume of the internal…

High Energy Physics - Theory · Physics 2013-08-15 Antonino Flachi , Masato Minamitsuji , Kunihito Uzawa

We consider static cosmological solutions along with their stability properties in the framework of a recently proposed theory of massive gravity. We show that the modifcation introduced in the cosmological equations leads to several new…

General Relativity and Quantum Cosmology · Physics 2012-07-27 Luca Parisi , Ninfa Radicella , Gaetano Vilasi

The Dolgov-Kawasaki instability discovered in the matter sector of the modified gravity scenario incorporating a 1/R correction to Einstein gravity is studied in general f(R) theories. A stability condition is found in the metric version of…

Astrophysics · Physics 2008-11-26 Valerio Faraoni

We consider several classes of degenerate hyperbolic equations involving delay terms and suitable nonlinearities. The idea is to rewrite the problems in an abstract way and, using semigroup theory and energy method, we study well posedness…

Analysis of PDEs · Mathematics 2024-07-16 Alessandro Camasta , Genni Fragnelli , Cristina Pignotti

We will present the way to derive a de Sitter inflationary solution within the so-called Starobinsky-Bel-Robinson gravity. Then, we will show by using the dynamical system method whether the obtained solution is stable or not. According to…

General Relativity and Quantum Cosmology · Physics 2025-07-10 Tuan Q. Do

In this paper we investigate cosmological dynamics on the normal branch of a DGP-inspired scenario within a phase space approach where induced gravity is modified in the spirit of $f(R)$-theories. We apply the dynamical system analysis to…

General Relativity and Quantum Cosmology · Physics 2015-05-19 Kourosh Nozari , Faeze Kiani

In this article, we review and discuss different aspects of stability and genericity of some properties of space-times which occur in various contexts in the General Theory of Relativity. We also give argument supporting the conclusion that…

General Relativity and Quantum Cosmology · Physics 2016-12-30 R. V. Saraykar