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Related papers: Cosmological dynamics of R^n gravity

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We reconcile seemingly conflicting statements in the literature about the behavior of cosmological solutions in modified theories of gravity where the Einstein-Hilbert Lagrangian for gravity is modified by the addition of a function of the…

Astrophysics · Physics 2008-11-26 Ignacy Sawicki , Wayne Hu

In this article, we examine the dynamical evolution of flat FRW cosmological model in $f(R, L_m)$ gravity theory. We consider the general form of $f(R, L_m)$ defined as $f(R, L_m) = \Lambda + \frac{\alpha}{2} R + \beta L_m^n$, where…

General Relativity and Quantum Cosmology · Physics 2025-02-14 Aman Shukla , Rakesh Raushan , Raghavendra Chaubey

$f(R)$ gravity is one of the simplest theories of modified gravity to explain the accelerated cosmic expansion. Although it is usually assumed that the quasi-Newtonian approach (a combination of the quasi-static approximation and sub-Hubble…

General Relativity and Quantum Cosmology · Physics 2015-12-02 Mu-Chen Chiu , Andy Taylor , Chenggang Shu , Hong Tu

In this paper we exploit the theory of the dynamical systems to study the dynamics of the standard cosmological model of the universe, which is known as the $\Lambda$CDM model. We assume that the matter content in our universe consists of…

General Physics · Physics 2022-09-07 Danijela Branković , Žarko Mijajlović

We consider that the cosmological constant is associated with the vacuum energy density of a particle physics model. In the path integral formalism of euclidean quantum gravity and in the background of the Robertson Walker metric we…

General Physics · Physics 2020-01-28 Renata Jora

We investigated a flat multidimensional cosmological model in Gauss-Bonnet gravity in presence of a matter in form of perfect fluid. We found analytically new stationary regimes (these results are valid for arbitrary number of spatial…

General Relativity and Quantum Cosmology · Physics 2015-03-13 I. V. Kirnos , S. A. Pavluchenko , A. V. Toporensky

In this paper cosmological dynamics in Einstein-Gauss-Bonnet gravity with a perfect fluid source in arbitrary dimension is studied. A systematic analysis is performed for the case that the theory does not admit maximally symmetric…

General Relativity and Quantum Cosmology · Physics 2018-03-15 Fabrizio Canfora , Alex Giacomini , Sergey A. Pavluchenko , Alexey Toporensky

The dynamical aspect of accelerating cosmological model has been studied in this paper in the context of modified symmetric teleparallel gravity, the $f(Q)$ gravity. Initially, we have derived the dynamical parameters for two well known…

General Relativity and Quantum Cosmology · Physics 2023-07-18 S. A. Narawade , Shashank P. Singh , B. Mishra

In this work, we study cosmological and astrophysical applications of the recently proposed generalized hybrid metric-Palatini gravity theory, which combines features of both the metric and the Palatini approaches to the variational method…

General Relativity and Quantum Cosmology · Physics 2019-11-20 João Luís Rosa

We analyze the cosmological solutions of $f(T,B)$ gravity using dynamical system analysis where $T$ is the torsion scalar and $B$ be the boundary term scalar. In our work, we assume two specific cosmological models. For first model, we…

General Relativity and Quantum Cosmology · Physics 2023-04-26 Amit Samaddar , S. Surendra Singh

By regarding the vacuum as a perfect fluid with equation of state p=-rho, de Sitter's cosmological model is quantized. Our treatment differs from previous ones in that it endows the vacuum with dynamical degrees of freedom. Instead of being…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Flavio G. Alvarenga , Nivaldo A. Lemos

Numerical N-body simulations of large scale structure formation in the universe are based on Newtonian gravity. However, according to our current understanding, the most correct theory of gravity is general relativity. It is therefore…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-27 Ugo Bertello

We consider a very general scenario of our universe where its geometry is characterized by the Finslerian structure on the underlying spacetime manifold, a generalization of the Riemannian geometry. Now considering a general energy-momentum…

General Relativity and Quantum Cosmology · Physics 2018-03-28 Nupur Paul , S. S. De , Farook Rahaman

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

We investigate the out-of-equilibrium dynamics of viscous fluids in a spatially flat Friedmann-Lema\^itre-Robertson-Walker cosmology using the most general causal and stable viscous energy-momentum tensor defined at first order in spacetime…

General Relativity and Quantum Cosmology · Physics 2023-07-31 Fábio S. Bemfica , Marcelo M. Disconzi , Jorge Noronha , Robert J. Scherrer

In this letter, we investigate the cosmic expansion scenario of the universe in the framework of $f(R,L_m)$ gravity theory. We consider a non-linear $f(R,L_m)$ model, specifically, $f(R,L_m)=\frac{R}{2}+L_m^n + \beta$, where $n$ and $\beta$…

General Relativity and Quantum Cosmology · Physics 2023-11-02 Lakhan V. Jaybhaye , Raja Solanki , Sanjay Mandal , P. K. Sahoo

We investigate the cosmological behavior of mimetic F(R) gravity. This scenario is the F(R) extension of usual mimetic gravity classes, which are based on re-parametrizations of the metric using new, but not propagating, degrees of freedom,…

General Relativity and Quantum Cosmology · Physics 2015-04-22 Genly Leon , Emmanuel N. Saridakis

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

We study cosmological dynamics of the cuscuta-galileon gravity with a potential term by using the dynamical system approach. This model is galileon generalization of the cuscuton gravity where we add a potential term to the theory in order…

General Relativity and Quantum Cosmology · Physics 2023-03-23 Sirachak Panpanich , Kei-ichi Maeda

In this paper we analyze the asymptotic behavior of Cardassian cosmological models filled with a perfect fluid and a scalar field with an exponential potential. Cardassian cosmologies arise from modifications of the Friedmann equation, and…

Astrophysics · Physics 2016-08-30 Ruth Lazkoz , Genly Leon