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Related papers: Screening Solutions in Modified Gravity Theories

200 papers

We present a formalism to study screening mechanisms in modified theories of gravity via perturbative methods in different cosmological scenarios. We consider Einstein frame posed theories that are recast as Jordan frame theories, where a…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-30 Alejandro Aviles , Jorge L. Cervantes-Cota , David F. Mota

Current constraints on gravity are relatively weak on galactic and intergalactic scales. Screened modified gravity models can exhibit complex behaviour there without violating stringent tests of gravity within our Solar System. They might…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-15 Aneesh P. Naik , Ewald Puchwein , Anne-Christine Davis , Christian Arnold

Modified gravity models which include an additional propagating degree of freedom are typically studied in the quasi-static limit, where the propagation is neglected, and the wave equation of the field is replaced with a Poisson-type…

General Relativity and Quantum Cosmology · Physics 2018-07-04 Hiu Yan Sam Ip , Fabian Schmidt

Future space-based tests of relativistic gravitation-laser ranging to Phobos, accelerometers in orbit, and optical networks surrounding Earth-will constrain the theory of gravity with unprecedented precision by testing the inverse-square…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-28 Jeremy Sakstein

We consider cosmological models where dark energy is described by a dynamical field equipped with the Chameleon screening mechanism, which serves to hide its effects in local dense regions and to conform to Solar System observations. In…

General Relativity and Quantum Cosmology · Physics 2020-07-22 Macarena Lagos , Hanjue Zhu

Here we explore the possibility of extending to the Solar System scenario the combined residual approach employed for the deterination of the Lense-Thirring effect in the Earth-LAGEOS satellites system. After calculating the secular…

General Relativity and Quantum Cosmology · Physics 2013-11-04 Lorenzo Iorio

The chameleon screening mechanism has been constrained many a time using dynamic and kinematic galaxy cluster observables. Current constraints are, however, insensitive to different mass components within galaxy clusters and have been…

We consider the scalar field profile around relativistic compact objects such as neutron stars for a range of modified gravity models with screening mechanisms of the chameleon and Damour-Polyakov types. We focus primarily on inverse power…

General Relativity and Quantum Cosmology · Physics 2017-04-19 Philippe Brax , Anne-Christine Davis , Rahul Jha

Using a novel and self-consistent approach that avoids the scalar-tensor identification in the Einstein frame, we reanalyze the viability of f(R) gravity within the context of solar-system tests. In order to do so, we depart from a simple…

General Relativity and Quantum Cosmology · Physics 2020-03-06 Carolina Negrelli , Lucila Kraiselburd , Susana J. Landau , Marcelo Salgado

We investigate the effect of modifed gravity with screening mechanisms, such as the chameleon or symmetron models, upon the structure of main sequence stars. We find that unscreened stars can be significantly more luminous and ephemeral…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-17 Anne-Christine Davis , Eugene A. Lim , Jeremy Sakstein , Douglas J. Shaw

We present a framework for embedding scalar-tensor models of screened modifed gravity such as chameleons, symmetrons and environmental dilatons into global supersymmetry. This achieved by secluding the dark sector from both the observable…

High Energy Physics - Theory · Physics 2015-06-12 Philippe Brax , Anne-Christine Davis , Jeremy Sakstein

Screened modified gravity theories evade the solar system tests that have proved prohibitive for classical alternative gravity theories. In many cases, they do not fit into the PPN formalism. The environmental dependence of the screening…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-12 Jeremy Sakstein

Scalar-tensor theories whose phenomenology differs significantly from general relativity on large (e.g. cosmological) scales do not typically pass local experimental tests (e.g. in the solar system) unless they present a suitable "screening…

General Relativity and Quantum Cosmology · Physics 2021-10-13 Alexandru Dima , Miguel Bezares , Enrico Barausse

We propose a simple and computationally fast method for performing N-body simulations for a large class of modified gravity theories with a screening mechanism such as chameleons, symmetrons and galileons. By combining the linear…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Hans A. Winther , Pedro G. Ferreira

This article investigates the profile of the scalar field of a scalar-tensor theory subject to the chameleon mechanism in the context of gravity space missions like the MICROSCOPE experiment. It analyses the experimental situations for…

General Relativity and Quantum Cosmology · Physics 2019-10-09 Martin Pernot-Borràs , Joel Bergé , Philippe Brax , Jean-Philippe Uzan

The laws of gravitation have been tested for a long time with steadily improving precision, leading at some moment of time to paradigmatic evolutions. Pursuing this continual effort is of great importance for science. In this communication,…

General Relativity and Quantum Cosmology · Physics 2023-04-14 A. Hees , P. Wolf , B. Lamine , S. Reynaud , M. T. Jaekel , C. Le Poncin-Lafitte , V. Lainey , V. Dehant

Light scalar fields can drive the accelerated expansion of the universe. Hence, they are obvious dark energy candidates. To make such models compatible with tests of General Relativity in the solar system and "fifth force" searches on…

Instrumentation and Methods for Astrophysics · Physics 2014-11-07 S. Baum , G. Cantatore , D. H. H. Hoffmann , M. Karuza , Y. K. Semertzidis , A. Upadhye , K. Zioutas

Modified gravity theories can produce strong signals in the vicinity of the saddles of the total gravitational potential. In a sub-class of these models this translates into diverging time-delays for echoes crossing the saddles. Such models…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Joao Magueijo , Ali Mozaffari

In this work we systematically study the linear and nonlinear structure formation in chameleon theories of modified gravity, using a generic parameterisation which describes a large class of models using only 4 parameters. For this we have…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-24 Philippe Brax , Anne-C. Davis , Baojiu Li , Hans A. Winther , Gong-Bo Zhao

Theories of gravity that incorporate new scalar degrees of freedom typically require screening mechanisms to ensure consistency with Solar System tests. One widely-studied mechanism -- the chameleon -- can lead to violations of the…

Astrophysics of Galaxies · Physics 2020-11-24 A. P. Naik , N. W. Evans , E. Puchwein , H. Zhao , A. -C. Davis