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Related papers: Dynamical behavior in mimetic F(R) gravity

200 papers

A review of the new of the problem of dark energy using modified gravity approach is considered. An explanation of the difficulties facing modern cosmology is given and different approaches are presented. We show why some models of gravity…

General Relativity and Quantum Cosmology · Physics 2014-06-18 Ahmed Alhamzawi , Rahim Alhamzawi

In this work, we study the late-time cosmological solutions of f(R,T)=g(R)+h(-T) models assuming that the conservation of the energy-momentum tensor (EMT) is violated. We perform our analysis through constructing an autonomous dynamical…

General Relativity and Quantum Cosmology · Physics 2017-08-07 Hamid Shabani , Amir Hadi ziaie

Several f(R) modified gravity models have been proposed which realize the correct cosmological evolution and satisfy solar system and laboratory tests. Although nonrelativistic stellar configurations can be constructed, we argue that…

Astrophysics · Physics 2009-02-20 Tsutomu Kobayashi , Kei-ichi Maeda

Mimetic gravity is a Weyl-symmetric extension of General Relativity, related to the latter by a singular disformal transformation, wherein the appearance of a dust-like perfect fluid can mimic cold dark matter at a cosmological level.…

General Relativity and Quantum Cosmology · Physics 2017-03-03 L. Sebastiani , S. Vagnozzi , R. Myrzakulov

We reconstruct $F(\mathcal{G})$ gravity theory with an exponential scale factor to realize the bouncing behavior in the early universe and examine the asymptotic behaviour of late-time solutions in this model. We propose an approach to the…

General Relativity and Quantum Cosmology · Physics 2017-11-15 Andrey N. Makarenko , Alexander N. Myagky

The exponential $f(R)$ gravity model provides a theoretically well-motivated extension of General Relativity, introducing a modified gravitational dynamics at late times consistent with a dynamical dark energy scenario, while recovering the…

General Relativity and Quantum Cosmology · Physics 2025-11-11 Simone D'Onofrio , Sergei Odintsov , Tiziano Schiavone

In this work we investigate several theoretical and phenomenological implications of a scalar -$F(R)$ gravity containing a non-minimal coupling to the scalar curvature. This kind of model is a generalization of axion-$F(R)$ gravity models,…

General Relativity and Quantum Cosmology · Physics 2020-05-20 Shin'ichi Nojiri , S. D. Odintsov , V. K. Oikonomou

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

It has been recently proposed that gravity might be an entropic force. Although a well defined fundamental description for such a mechanism is still lacking, it is still possible to address the viability of phenomenological models of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Miguel Zumalacarregui

We investigate the cosmological implications of $f(Q)$ gravity, which is a modified theory of gravity based on non-metricity, in non-flat geometry. We perform a detailed dynamical-system analysis keeping the $f(Q)$ function completely…

General Relativity and Quantum Cosmology · Physics 2023-06-26 Hamid Shabani , Avik De , Tee-How Loo , Emmanuel N. Saridakis

We investigate the evolution of a spatially flat Friedmann-Robertson-Walker (FRW) universe in the framework of scalar non-metricity theory of gravity. In the model, we consider dark matter (DM) and dark energy (DE) described by the scalar…

General Relativity and Quantum Cosmology · Physics 2025-08-05 Bikash Chandra Roy , Bikash Chandra Paul

We study FRW homogeneous cosmological solutions in the recently found ghost free massive gravity. In previous works it was shown that when the additional extra metric, needed to generate the mass term, is taken as non-dynamical and flat, no…

High Energy Physics - Theory · Physics 2012-05-21 D. Comelli , M. Crisostomi , F. Nesti , L. Pilo

The growth of large scale structure is a battle between gravitational attraction and cosmic acceleration. We investigate the future behavior of cosmic growth under both general relativity (GR) and modified gravity during prolonged…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-09 Eric V. Linder , David Polarski

We study cosmologies in modified theories of gravity considering Lagrangian density $f(R)$ which is a polynomial function of scalar curvature ($R$) in the Einstein-Hilbert action in vacuum. The field equation obtained from the modified…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-29 B. C. Paul , P. S. Debnath , S. Ghose

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

In this paper, we shall consider $f(R)$ gravity and its cosmological implications, when an extra matter term generated by thermal effects is added by hand in the Lagrangian. We formulate the equations of motion of the theory as a dynamical…

General Relativity and Quantum Cosmology · Physics 2020-09-29 V. K. Oikonomou , F. P. Fronimos , N. Th. Chatzarakis

This paper delves into the late-time accelerated expansion of the universe and the evolution of cosmic structures within the context of a specific \( f(R, L_m) \) gravity model, formulated as \( f(R, L_m) = \lambda R + \beta L_m^\alpha +…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-05 Shambel Sahlu , Alnadhief H. A. Alfedeel , Amare Abebe

In this work, we use the dynamical system approach to explore the cosmological background evolution of the scalar-tensor representation of $f(R,T)$ gravity, where $R$ is the Ricci scalar and $T$ is the trace of the stress-energy tensor. The…

General Relativity and Quantum Cosmology · Physics 2024-04-04 Tiago B. Gonçalves , João Luís Rosa , Francisco S. N. Lobo

We explore the cosmological evolution in the exponential gravity $f(R)=R +c_1 (1-e^{- c_2 R})$ ($c_{1, 2} = \mathrm{constant}$). We summarize various viability conditions and explicitly demonstrate that the late-time cosmic acceleration…

Cosmology and Nongalactic Astrophysics · Physics 2010-09-10 Kazuharu Bamba , Chao-Qiang Geng , Chung-Chi Lee

We study the metric perturbations in the context of restricted $f(R)$ gravity, in which a parameter for deviation from the full diffeomorphisms of space-time is introduced. We demonstrate that one can choose the parameter to remove the…

General Relativity and Quantum Cosmology · Physics 2016-03-15 Amir Ghalee