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Related papers: New late-time constraints on $f(R)$ gravity

200 papers

We investigate to which extent a time variation of the gravitational constant or other fundamental constants affects the best fit of the Hubble diagram of type Ia supernovae. In particular, we show that a slow increase of $G$ in the past,…

Astrophysics · Physics 2007-05-23 Luca Amendola , Stefano Corasaniti , Franco Occhionero

Most of the information on our cosmos stems from either late-time observations or the imprint of early-time inhomogeneities on the cosmic microwave background. We explore to what extent early modifications of gravity, which become…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-10 Nelson A. Lima , Vanessa Smer-Barreto , Lucas Lombriser

Dynamical behavior and future singularities of $f(R, T,R_{\mu\nu}T^{\mu\nu})$ gravitational theory are investigated. This gravitational model is a more complete form of the $f(R,T)$ gravity which can offer new dynamics for the universe. We…

General Relativity and Quantum Cosmology · Physics 2020-04-06 Maryam Aghaei Abchouyeh , Behrouz Mirza , Parisa Shahidi , Fatemeh Oboudiat

We discuss solar system constraints on f(G) gravity models, where f is a function of the Gauss-Bonnet term G. We focus on cosmologically viable f(G) models that can be responsible for late-time cosmic acceleration. These models generally…

High Energy Physics - Theory · Physics 2010-03-26 Antonio De Felice , Shinji Tsujikawa

This study conducts a meticulous examination of the cosmological implications inherent in Rastall gravity and $f(R)$ gravity models, assessing their efficacy across distinct cosmic epochs, from early universe structure formation to…

General Relativity and Quantum Cosmology · Physics 2025-01-14 Muhammad Yarahmadi , Amin Salehi , Hadis Mousavi

Here in this work we propose a modified gravity with the action of $f(R) = \sqrt{R^2 - R_0^2}$ instead of Einstein-Hilbert action to describe the late time acceleration of the universe. We obtain the equation of the modified gravity both in…

Astrophysics · Physics 2008-11-26 Shant Baghram , Marzieh Farhang , Sohrab Rahvar

We test General Relativity (GR) using current cosmological data: the cosmic microwave background (CMB) from WMAP5 (Komatsu et al. 2009), the integrated Sachs-Wolfe (ISW) effect from the cross-correlation of the CMB with six galaxy catalogs…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-19 Gong-Bo Zhao , Tommaso Giannantonio , Levon Pogosian , Alessandra Silvestri , David J. Bacon , Kazuya Koyama , Robert C. Nichol , Yong-Seon Song

Within the $f(Q)$-gravity framework we perform a phenomenological study of the cosmological observables in light of the degeneracy between neutrinos physics and the modified gravity parameter and we identify specific patterns which allow to…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-12 Luís Atayde , Noemi Frusciante

As an important candidate gravity theory alternative to dark energy, a class of $f(R)$ modified gravity, which introduces a perturbation of the Ricci scalar $R$ in the Einstein-Hilbert action, has been extensively applied to cosmology to…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-18 Tengpeng Xu , Shuo Cao , Jingzhao Qi , Marek Biesiada , Xiaogang Zheng , Zong-Hong Zhu

Nonlocal massive gravity can provide an interesting explanation for the late-time cosmic acceleration, with a dark energy equation of state $w_{\rm DE}$ smaller than $-1$ in the past. We derive the equations of linear cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-11 Savvas Nesseris , Shinji Tsujikawa

We consider recently proposed higher order gravity models where the action is built from the Einstein-Hilbert action plus a function f(G) of the Gauss-Bonnet invariant. The models were previously shown to pass physical acceptability…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-19 Jacob Moldenhauer , Mustapha Ishak , John Thompson , Damien A. Easson

The growing tensions between the early Universe and the late Universe increasingly highlight the importance of developing precise probes for late cosmology. As significant late-Universe probes, Type Ia supernovae (SNe Ia) and gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-09 Jie Zheng , Xiao-Hui Liu , Jing-Zhao Qi

We study new FRW type cosmological models of modified gravity treated on the background of Palatini approach. These models are generalization of Einstein gravity by the presence of a scalar field non-minimally coupled to the curvature. The…

General Relativity and Quantum Cosmology · Physics 2012-03-13 A. Borowiec , M. Kamionka , A. Kurek , M. Szydlowski

We propose a novel model in the framework of $f(Q)$ gravity, which is a gravitational modification class arising from the incorporation of non-metricity. The model has General Relativity as a particular limit, it has the same number of free…

General Relativity and Quantum Cosmology · Physics 2021-09-15 Fotios K. Anagnostopoulos , Spyros Basilakos , Emmanuel N. Saridakis

Over the last few years much attention has been given to the study of modified gravity theories in order to find a more natural explanation for the late time acceleration of the Universe. Nevertheless, a comparison of the matter power…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Amare Abebe , Alvaro de la Cruz Dombriz , Peter K. S. Dunsby

In this study, we investigate gravitational lensing within modified gravity frameworks, focusing on the Hu-Sawicki $f(R)$ and normal branch Dvali-Gabadadze-Porrati (nDGP) models, and we compare these results with those obtained from general…

General Relativity and Quantum Cosmology · Physics 2025-01-03 Ali Tizfahm , Saeed Fakhry , Javad T. Firouzjaee , Antonino Del Popolo

The review of basic cosmological properties of four-dimensional F(R)-gravity, including FRW equations of motion and its accelerating solutions, generalized fluid and scalar-tensor representation of the theory is done. Cosmological…

High Energy Physics - Theory · Physics 2015-05-19 Shin'ichi Nojiri , Sergei D. Odintsov

The Hubble constant tension problem is analysed in the framework of a class of modified gravity, the so-called $F(R)$ gravity. To do so, we explore two models: an exponential and a power-law $F(R)$ gravities, which includes an early dark…

General Relativity and Quantum Cosmology · Physics 2021-03-24 Sergei D. Odintsov , Diego Sáez-Chillón Gómez , German S. Sharov

We investigate $f\left( Q\right) $-gravity with a matter-gravity coupling as a geometric dark energy candidate for the description of the late-time cosmic acceleration within a spatially flat Friedmann--Lema\^{\i}tre-Robertson-Walker…

General Relativity and Quantum Cosmology · Physics 2026-03-24 Andronikos Paliathanasis

We constrain the Hu-Sawicki and Starobinsky $f(R)$ gravity models utilizing current electromagnetic (PP+CC, Planck and DESI2) datasets and simulate standard siren catalogs based on the resulting best-fit parameters. We demonstrate that the…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-05 Yi Zhang , Xuanjun Niu , Xianfu Su , Dong-Ze He
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