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Related papers: A Unified Description of Screened Modified Gravity

200 papers

Modified gravity theories can be used for the description of homogeneous and isotropic cosmological models through the corresponding field equations. These can be cast into systems of autonomous differential equations because of their sole…

General Relativity and Quantum Cosmology · Physics 2024-04-08 Christian G. Boehmer , Erik Jensko , Ruth Lazkoz

$R^2$-corrected dark energy (DE) models in $F(R)$ gravity have been widely investigated in recent years, which not only removes the weak singularity potentially present in DE models but also provide us with a unified picture of the cosmic…

General Relativity and Quantum Cosmology · Physics 2022-10-12 Hua Chen , Taishi Katsuragawa , Shinya Matsuzaki

In certain theories of modified gravity, solar system constraints on deviations from general relativity (GR) are satisfied by virtue of a so-called screening mechanism, which enables the theory to revert to GR in regions where the matter…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-01 Difu Shi , Baojiu Li , Jiaxin Han

A conformal coupling of the metric in the Jordan frame to the energy-momentum tensor, screens the scalar field gravitational coupling strength $G$ in modified gravity (MOG). The scalar field acquires a mass which depends on the local matter…

General Relativity and Quantum Cosmology · Physics 2014-10-14 J. W. Moffat

In this work we explore the dynamics of the generalized hybrid metric-Palatini theory of gravity in the weak-field, slow-motion regime. We start by introducing the equivalent scalar-tensor representation of the theory, which contains two…

General Relativity and Quantum Cosmology · Physics 2021-12-14 João Luís Rosa , Francisco S. N. Lobo , Gonzalo J. Olmo

Screened modified gravity (SMG) and Brans-Dicke (BD) gravity are typical examples of scalar-tensor theories with and without screening mechanisms, which can suppress the scalar field in dense regions. In this paper, we investigate the tests…

General Relativity and Quantum Cosmology · Physics 2019-07-22 Xing Zhang , Rui Niu , Wen Zhao

Modified gravity theories have received increased attention lately to understand the late time acceleration of the universe. This viewpoint essentially modifies the geometric components of the universe. Among numerous extension to…

General Relativity and Quantum Cosmology · Physics 2019-05-23 Parth Shah , Gauranga C. Samanta

When it comes to searches for extensions to general relativity, large efforts are being dedicated to accurate predictions for the power spectrum of density perturbations. While this observable is known to be sensitive to the gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-08 Claudio Llinares , Nuala McCullagh

We offer predictions of symmetron modified gravity in the neighborhood of realistic dark matter halos. The predictions for the fifth force are obtained by solving the nonlinear symmetron equation of motion in the spherical NFW…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Joseph Clampitt , Bhuvnesh Jain , Justin Khoury

We describe and demonstrate the potential of a new and very efficient method for simulating certain classes of modified gravity theories, such as the widely studied $f(R)$ gravity models. High resolution simulations for such models are…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-14 Sownak Bose , Baojiu Li , Alexandre Barreira , Jian-hua He , Wojciech A. Hellwing , Kazuya Koyama , Claudio Llinares , Gong-Bo Zhao

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

Modified theories of gravity that offer viable models for dark energy often rely on mechanisms that screen their effects in high density environments. From this perspective, it would appear that, once solar system constraints are satisfied,…

General Relativity and Quantum Cosmology · Physics 2020-07-24 Bernardo F. de Aguiar , Raissa F. P. Mendes

In chameleon field theories a scalar field can couple to matter with gravitational strength and still evade local gravity constraints due to a combination of self-interactions and the couplings to matter. Originally, these theories were…

Cosmology and Nongalactic Astrophysics · Physics 2011-05-02 David F. Mota , Hans A. Winther

Modifying the Einstein's gravity at large distance scales is one of the interesting proposals to explain the late time acceleration of the universe. In this paper, we analyse scaling solutions in modified gravity models where the universe…

Astrophysics · Physics 2009-06-23 A. A Sen , N. Chandrachani Devi

As cosmology rapidly approaches the data-dominated phase of stage IV large scale structure surveys, the modelling of nonlinear scales has become a serious challenge that faces the community, particularly when analysing models beyond $w$CDM.…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-14 Sankarshana Srinivasan , Shreya Prabhu , Kai Lehman , Ajiv Krishnan V. , Jochen Weller

We investigate the impact of modified-gravity models on the Lyman-$\alpha$ power spectrum. Building a simple analytical modeling, based on a truncated Zeldovich approximation, we estimate the intergalactic medium power spectrum and the…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-30 Philippe Brax , Patrick Valageas

Many theories of modified gravity, including the well studied Horndeski models, are characterized by a screening mechanism that ensures that standard gravity is recovered near astrophysical bodies. In a recently introduced class of…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Ryo Saito , Daisuke Yamauchi , Shuntaro Mizuno , Jérôme Gleyzes , David Langlois

Emergent modified gravity presents a new set of generally covariant gravitational theories in which the space-time metric is not directly given by one of the fundamental fields. A metric compatible with the modified dynamics of gravity is…

General Relativity and Quantum Cosmology · Physics 2024-04-09 Martin Bojowald , Erick I. Duque

We study the cosmological evolution of an induced gravity model with a scale symmetry breaking potential for the scalar field. The radiation to matter transition, following inflation and reheating, influences the dynamics of such a field…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Alexander Y. Kamenshchik , Alessandro Tronconi , Giovanni Venturi

Modified theories of gravity provide us with a unique opportunity to generate innovative tests of gravity. In Chameleon f(R) gravity, the gravitational potential differs from the weak-field limit of general relativity (GR) in a mass…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-26 Alejo Stark , Christopher J. Miller , Nicholas Kern , Daniel Gifford , Gong-Bo Zhao , Baojiu Li , Kazuya Koyama , Robert C. Nichol