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Related papers: Modified gravity models of dark energy

200 papers

Cosmologists today are confronted with the perplexing reality that the universe is currently accelerating in its expansion. Nevertheless, the nature of the fuel that drives today's cosmic acceleration is an open and tantalizing mystery.…

Astrophysics · Physics 2008-11-26 Arthur Lue

We perform cosmological N-body simulations of the Dvali-Gabadadze-Porrati braneworld model, by solving the full non-linear equations of motion for the scalar degree of freedom in this model, the brane bending mode. While coupling…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-28 Fabian Schmidt

This study aims to explore the Garcia-Salcedo ghost dark energy and generalized ghost dark energy models in the context of $f(\mathrm{R},\mathrm{T^2})$ theory, where $\mathrm{R}$ is the Ricci scalar and $\mathrm{T^2}$ is the…

General Relativity and Quantum Cosmology · Physics 2024-05-28 Muhammad Zeeshan Gul , Muhammad Sharif , Imran Hashim

The acceleration of the universe can be explained either through dark energy or through the modification of gravity on large scales. In this paper we investigate modified gravity models and compare their observable predictions with dark…

Astrophysics · Physics 2008-11-26 Edmund Bertschinger , Phillip Zukin

The modified gravity is considered in the framework of the holographic dark energy. An analysis of the autonomous system, the critical points and their stability is presented. Unlike the dark energy models based on $f(R)$, it is found that…

General Relativity and Quantum Cosmology · Physics 2020-03-18 L. N. Granda , G. D. Rojas

Dark energy cosmology is considered in a modified Gauss-Bonnet model of gravity with and without a scalar field. It is shown that these generalizations of General Relativity endow it with a very rich cosmological structure: it may naturally…

General Relativity and Quantum Cosmology · Physics 2015-05-18 Emilio Elizalde , Ratbay Myrzakulov , Valery V. Obukhov , Diego Sáez-Gómez

The actual accelerated expansion of the universe continues being a mystery in physics. Some models had been proposed for this explanations, among them the dark energy, which however has problems of experimental character as well as…

General Relativity and Quantum Cosmology · Physics 2012-11-13 Alejandro Guarnizo

Recently, the phenomenology of f(R) gravity has been scrutinized motivated by the possibility to account for the self-accelerated cosmic expansion without invoking dark energy sources. Besides, this kind of modified gravity is capable of…

General Relativity and Quantum Cosmology · Physics 2015-08-28 Salvatore Capozziello , Tiberiu Harko , Tomi S. Koivisto , Francisco S. N. Lobo , Gonzalo J. Olmo

In this work, we reconstruct the $f(R)$ modified gravity for different ghost and generalized ghost dark energy models in FRW flat universe, which describe the accelerated expansion of the universe. The equation of state of reconstructed…

High Energy Physics - Theory · Physics 2012-06-06 A. Khodam-Mohammadi , M. Malekjani , M. Monshizadeh

We propose a simple higher-derivative braneworld gravity model which contains a stable accelerating branch, in the absence of cosmological constant or potential, that can be used to describe the late time cosmic acceleration. This model has…

High Energy Physics - Theory · Physics 2009-11-11 Claudia de Rham , Andrew J. Tolley

The Dvali-Gabadadze-Porrati brane-world model provides a possible approach to address the late-time cosmic acceleration. However, it has subsequently been pointed out that a ghost instability will arise on the self-accelerating branch.…

High Energy Physics - Theory · Physics 2019-02-13 Yen-Wei Liu , Keisuke Izumi , Mariam Bouhmadi-Lopez , Pisin Chen

Despite the nice features of the Dvali, Gabadadze and Porrati (DGP) model to explain the late-time acceleration of the universe, it suffers from some theoretical problems like the ghost issue. We present a way to self-accelerate the normal…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Mariam Bouhmadi-Lopez

We study spherically symmetric solutions in f(R) theories and its compatibility with local tests of gravity. We start by clarifying the range of validity of the weak field expansion and show that for many models proposed to address the Dark…

General Relativity and Quantum Cosmology · Physics 2010-10-27 I. Navarro , K. Van Acoleyen

We study the thermodynamics of some cosmological models based on modified gravity, a braneworld with induced gravity and curvature effect. Dark energy component seems necessary if the models are to approach thermal equilibrium in the long…

General Relativity and Quantum Cosmology · Physics 2011-09-16 Ninfa Radicella , Diego Pavón

Observations exploring the contemporary cosmic acceleration have sparked interest in dark energy models possessing equations of state with w < -1. We review how the cosmic expansion history of a Dvali-Gabadadze-Porrati (DGP) braneworld…

Astrophysics · Physics 2011-07-18 Arthur Lue , Glenn D. Starkman

Explanations to the accelerated expansion of the Universe are usually sought either in modifications of Einstein gravity or in new forms of energy density. An example of modified gravity is the braneworld Dvali-Gabadadze-Porrati (DGP) model…

Astrophysics · Physics 2008-04-22 Matts Roos

We solve for the behaviour of cosmological perturbations in the Dvali-Gabadadze-Porrati (DGP) braneworld model using a new numerical method. Unlike some other approaches in the literature, our method uses no approximations other than linear…

Astrophysics · Physics 2008-11-26 Antonio Cardoso , Kazuya Koyama , Sanjeev S. Seahra , Fabio P. Silva

In the current era of precision cosmology, the persistence of cosmological tensions, most notably the Hubble tension and the $S_8$ tension, challenges the standard $\Lambda$CDM model. To reconcile these tensions via late-time modifications…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-18 Yashi Tiwari , Ujjwal Upadhyay , Rajeev Kumar Jain

We construct a holographic dark energy model with a non-minimally coupled scalar field on the brane where Gauss-Bonnet and Induced Gravity effects are taken into account. This model provides a wide parameter space with several interesting…

General Relativity and Quantum Cosmology · Physics 2010-04-30 Kourosh Nozari , Narges Rashidi

The self-accelerating universe realizes the accelerated expansion of the universe at late times by large-distance modification of general relativity without a cosmological constant. The Dvali-Gabadadze-Porrati (DGP) braneworld model…

High Energy Physics - Theory · Physics 2008-11-26 Kazuya Koyama