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Related papers: Distinguishing modified gravity models

200 papers

We study structure formation in K-mouflage cosmology whose main feature is the absence of screening effect on quasilinear scales. We show that the growth of structure at the linear level is affected by both a new time dependent Newton…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-02 Philippe Brax , Patrick Valageas

We describe the effects of the cosmological background on the K-mouflage screening properties of an astrophysical structure. We show that the K-mouflage screening of the spatial gradients of the scalar field, i.e. the screening of the fifth…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-10 Philippe Brax , Patrick Valageas

We present a convolutional neural network to classify distinct cosmological scenarios based on the statistically similar weak-lensing maps they generate. Modified gravity (MG) models that include massive neutrinos can mimic the standard…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-17 Austin Peel , Florian Lalande , Jean-Luc Starck , Valeria Pettorino , Julian Merten , Carlo Giocoli , Massimo Meneghetti , Marco Baldi

A probability of distinguishing between $\Lambda$CDM model and modified gravity is studied by using the future observations for the growth rate of cosmic structure (Euclid redshift survey). Adopting extended DGP model, Kinetic Gravity…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-31 Koichi Hirano

Chameleon fields may modify gravity on cluster scales while recovering general relativity locally. This article reviews signatures of chameleon modifications in the nonlinear cosmological structure, comparing different techniques to model…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-06 Lucas Lombriser

Models of modified gravity offer promising alternatives to the concordance $\Lambda$CDM cosmology to explain the late-time acceleration of the universe. A popular such model is $f(R)$ gravity, in which the Ricci scalar in the…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-14 Christine Corbett Moran , Romain Teyssier , Baojiu Li

Modified Gravity theories generally affect the Poisson equation and the gravitational slip (effective anisotropic stress) in an observable way, that can be parameterized by two generic functions ($\eta$ and $\mu$) of time and space. We bin…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-06 Santiago Casas , Martin Kunz , Matteo Martinelli , Valeria Pettorino

Theories of modified gravity where light scalars with non-trivial self-interactions and non-minimal couplings to matter-chameleon and symmetron theories-dynamically suppress deviations from general relativity in the solar system. On other…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-20 Clare Burrage , Jeremy Sakstein

We study the impact of cosmological scale modifications to General Relativity on the dynamics of halos within voids by comparing N-body simulations incorporating Hu-Sawicki $f(R)$ gravity, with $|f_{R0}|=10^{-6}$ and $10^{-5}$, to those of…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-14 Christopher Wilson , Rachel Bean

Screened modified gravity predicts potentially large signatures in the peculiar velocity field that makes it an interesting probe to test gravity on cosmological scales. We investigate the signatures induced by the Symmetron and a Chameleon…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Max Gronke , Claudio Llinares , David F. Mota , Hans A. Winther

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 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

There has been a lot of research interest in modified gravity theories which utilise the Vainshtein mechanism to recover standard general relativity in regions with high matter density, such as the Dvali-Gabadadze-Porrati and Galileon…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-24 Baojiu Li , Gong-Bo Zhao , Kazuya Koyama

We introduce the Vainshtein mechanism which plays a crucial role in massive gravities, as well as in related theories such as Galileons and their extensions. This mechanism, also known as k-mouflage, allows to hide via non linear effects -…

General Relativity and Quantum Cosmology · Physics 2013-09-10 Eugeny Babichev , Cedric Deffayet

One way to account for the acceleration of the universe is to modify general relativity, rather than introducing dark energy. Typically, such modifications introduce new degrees of freedom. It is interesting to consider models with no new…

Astrophysics · Physics 2011-05-12 Sean M. Carroll , Ignacy Sawicki , Alessandra Silvestri , Mark Trodden

We investigate the dependence of the galaxy-halo connection and galaxy density field in modified gravity models using the $N-$body simulations for $f(R)$ and nDGP models at $z=0$. Because of the screening mechanisms employed by these…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-26 N. Chandrachani Devi , Aldo Rodríguez-Puebla , O. Valenzuela , Vladimir Avila-Reese , César Hernández-Aguayo , Baojiu Li

In theories of modified gravity with the chameleon screening mechanism, the strength of the fifth force depends on environment. This induces an environment dependence of structure formation, which differs from $\Lambda$CDM. We show that…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-06 Joaquin Armijo , Yan-Chuan Cai , Nelson Padilla , Baojiu Li , John A. Peacock

We consider metric-affine scenarios where a modified gravitational action is sourced by electrovacuum fields in a three dimensional space-time. Such scenarios are supported by the physics of crystalline structures with microscopic defects…

General Relativity and Quantum Cosmology · Physics 2015-08-13 Cosimo Bambi , M. Ghasemi-Nodehi , D. Rubiera-Garcia

Analysis of strong gravitational lensing depends on software analysis of observational data. The purpose of this study was to evaluate the behavior of strong gravitational lens modeling software with changes in redshift. Four different…

Instrumentation and Methods for Astrophysics · Physics 2013-07-19 Alan T. Lefor , Toshifumi Futamase

Astrophysical tests of modified modified gravity theories in the nearby universe have been emphasized recently by Hui, Nicolis and Stubbs (2009) and Jain and VanderPlas (2011). A key element of such tests is the screening mechanism whereby…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Anna Cabré , Vinu Vikram , Gong-Bo Zhao , Bhuvnesh Jain , Kazuya Koyama