English
Related papers

Related papers: Cosmological Dynamics from Modified $f(R)$ Gravity…

200 papers

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

$f(R)$ modifications of Einstein's gravity is an interesting possibility to explain the late time acceleration of the Universe. In this work we explore the cosmological viability of one such $f(R)$ modification proposed in (Kruglov:2013).…

General Relativity and Quantum Cosmology · Physics 2016-07-13 Koushik Dutta , Sukanta Panda , Avani Patel

We investigate the qualitative evolution of (D+1)-dimensional cosmological models in f(R) gravity for the general case of the function f(R). The analysis is specified for various examples, including the (D+1)-dimensional generalization of…

General Relativity and Quantum Cosmology · Physics 2016-02-03 R. M. Avagyan , E. V. Chubaryan , G. H. Harutyunyan , A. A. Saharian

In contrast to the phenomenon of nullification of the cosmological constant in the equilibrium vacuum, which is the general property of any quantum vacuum, there are many options in modifying the Einstein equation to allow the cosmological…

General Relativity and Quantum Cosmology · Physics 2009-11-10 G. E. Volovik

The study of modified gravity models has garnered significant attention because of their potential to provide alternative explanations for cosmological phenomena, such as the accelerated expansion of the universe and the nature of dark…

General Relativity and Quantum Cosmology · Physics 2025-05-27 Davood Momeni , Ratbay Myrzakulov

This thesis explores the late-time cosmic acceleration within the framework of $f(R,T)$ gravity, a general relativity modification that incorporates the Ricci scalar $R$ and the trace of the energy-momentum tensor $T$. Motivated by…

General Relativity and Quantum Cosmology · Physics 2025-07-29 Parbati Sahoo

We experience some challenges in general gravitational theory owing to Einstein to explain late time acceleration of universe. To address this issue, geometric components of gravity have been modified in quite a few occasions to have a more…

General Relativity and Quantum Cosmology · Physics 2024-10-04 Santanu Das , Nilanjana Mahata , Priyanka Ray

We study the evolution of linear cosmological perturbations in f(R) models of accelerated expansion in the physical frame where the gravitational dynamics are fourth order and the matter is minimally coupled. These models predict a rich and…

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

Over the past decade, f(R) theories have been extensively studied as one of the simplest modifications to General Relativity. In this article we review various applications of f(R) theories to cosmology and gravity - such as inflation, dark…

General Relativity and Quantum Cosmology · Physics 2013-11-12 Antonio De Felice , Shinji Tsujikawa

We analyze the background cosmology for an extension of the DGP gravity with Gauss-Bonnet term in the bulk and $f(R)$ gravity on the brane. We investigate implications of this setup on the late-time cosmic history. Within a dynamical system…

General Relativity and Quantum Cosmology · Physics 2014-01-15 Kourosh Nozari , Faeze Kiani , Narges Rashidi

In this work we consider the possibility of describing the current evolution of the universe, without the introduction of any cosmological constant or dark energy (DE), by modifying the Einstein-Hilbert (EH) action. In the context of the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 A. de la Cruz-Dombriz , A. Dobado

The current standard cosmological model is constructed within the framework of general relativity with a cosmological constant $\Lambda$, which is often associated with dark energy, and phenomenologically explains the accelerated cosmic…

General Relativity and Quantum Cosmology · Physics 2023-06-27 Jiamin Hou , Julian Bautista , Maria Berti , Carolina Cuesta-Lazaro , César Hernández-Aguayo , Tilman Tröster , Jinglan Zheng

We have investigated the evolution of a homogeneous isotropic background of the Universe and inhomogeneous subhorizon matter density perturbations in viable $f(R)$ models of present dark energy and cosmic acceleration analytically and…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-05 Hayato Motohashi , Alexei A. Starobinsky , Jun'ichi Yokoyama

In the present manuscript the basic Einstein--Hilbert cosmological model is extended, by adding a new functional $F(G, T_{\mu\nu}T^{\mu\nu})$ in the fundamental action, encoding specific geometrical effects due to a nontrivial coupling with…

General Relativity and Quantum Cosmology · Physics 2023-05-23 Mihai Marciu , Dana Maria Ioan

We present a bounce universe in modified $f(Q,C)$ gravity considering linear as well as exponential form of gravity. Bounce cosmological models are introduced to remove the singularity problem of the early universe. A new quadratic boundary…

General Relativity and Quantum Cosmology · Physics 2025-08-07 Bhaswati Mandal , B. C. Paul

We consider a class of metric f(R) modified gravity theories, analyze them in the context of a Friedmann-Robertson-Walker cosmology and confront the results with some of the known constraints imposed by observations. In particular, we focus…

General Relativity and Quantum Cosmology · Physics 2012-06-11 Luisa G. Jaime , Leonardo Patino , Marcelo Salgado

Modifications of general relativity provide an alternative explanation to dark energy for the observed acceleration of the universe. We review recent developments in modified gravity theories, focusing on higher dimensional approaches and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Bhuvnesh Jain , Justin Khoury

Taking into account the temperature corrections of the energy equipartition law for the bits of information that are coarse-grained on the holographic screen leads to a modification of Einstein's gravitational field equations. In the very…

General Relativity and Quantum Cosmology · Physics 2025-03-12 Kazem Rezazadeh

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

We explore the possibility of emergent cosmology using the effective potential formalism. We discover new models of emergent cosmology which satisfy the constraints posed by the cosmic microwave background (CMB). We demonstrate that, within…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-18 Satadru Bag , Varun Sahni , Yuri Shtanov , Sanil Unnikrishnan