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Related papers: Testing $f(R)$ Gravity With Scale Dependent Cosmic…

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In this paper, we study the distribution of dark matter halos and voids using high resolution simulations in f(R) gravity models with the chameleon mechanism to screen the fifth force in dense environment. For dark matter halos, we show…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-04 Baojiu Li , Gong-Bo Zhao , Kazuya Koyama

We investigate the behavior of the fifth force in voids in chameleon models using the spherical collapse method. Contrary to Newtonian gravity, we find the fifth force is repulsive in voids. The strength of the fifth force depends on the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-24 Joseph Clampitt , Yan-Chuan Cai , Baojiu Li

We investigate the impact of f(R) modified gravity on the internal properties of Milky Way sized dark matter halos in a set of cosmological zoom simulations of seven halos from the Aquarius suite, carried out with our code MG-GADGET in the…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-30 Christian Arnold , Volker Springel , Ewald Puchwein

We search for detectable signatures of f(R) gravity and its chameleon screening mechanism in the baryonic and dark matter (DM) properties of simulated void galaxies. The enhancement of the gravitational acceleration can have a meaningful…

Astrophysics of Galaxies · Physics 2022-08-17 Pedro Cataldi , Susana Pedrosa , Nelson Padilla , Susana Landau , Christian Arnold , Baojiu Li

We explore voids in dark matter and halo fields from simulations of $\Lambda$CDM and Hu-Sawicki $f(R)$ models. In $f(R)$ gravity, dark matter void abundances are greater than that of general relativity (GR). However, when using haloes to…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-06 Yan-Chuan Cai , Nelson Padilla , Baojiu Li

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

We investigate void properties in $f(R)$ models using N-body simulations, focusing on their differences from General Relativity (GR) and their detectability. In the Hu-Sawicki $f(R)$ modified gravity (MG) models, the halo number density…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-31 Yan-Chuan Cai , Nelson Padilla , Baojiu Li

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

Cosmic voids are becoming key players in testing the physics of our Universe. Here we concentrate on the abundances and the dynamics of voids as these are among the best candidates to provide information on cosmological parameters. Cai,…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-31 Nelson Padilla , Dante Paz , Marcelo Lares , Laura Ceccarelli , Diego Garcia Lambas , Yan-Chuan Cai , Baojiu Li

In chameleon $f(R)$-gravity, the fifth force will lead to `upturns' in galaxy rotation curves near the screening radius. The location of the upturn depends on the cosmic background value of the scalar field $f_{R0}$, as well as the mass,…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-06 Aneesh P. Naik , Ewald Puchwein , Anne-Christine Davis , Debora Sijacki , Harry Desmond

We present a systematic comparison of several existing and new void finding algorithms, focusing on their potential power to test a particular class of modified gravity models - chameleon $f(R)$ gravity. These models deviate from standard…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-14 Marius Cautun , Enrique Paillas , Yan-Chuan Cai , Sownak Bose , Joaquin Armijo , Baojiu Li , Nelson Padilla

Aims. We investigate the gravitational redshift in clusters of galaxies in the symmetron and Hu-Sawicky $f(R)$ models. The characteristic feature of both models is the screening mechanism that hides the fifth force in dense environments…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-05 Max B. Gronke , Claudio Llinares , David F. Mota

We have investigated structure formation in the $\gamma$ gravity $f(R)$ model with {\it N}-body simulations. The $\gamma$ gravity model is a proposal which, unlike other viable $f(R)$ models, not only changes the gravitational dynamics, but…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-09 Marcelo Vargas dos Santos , Hans A. Winther , David F. Mota , Ioav Waga

A key goal in cosmology in the upcoming decade will be to form a better understanding of the accelerated expansion of the Universe. Upcoming surveys, such as the Vera C. Rubin Observatory's 10-year Legacy Survey of Space and Time (LSST),…

General Relativity and Quantum Cosmology · Physics 2022-11-29 Andrius Tamosiunas , Chad Briddon , Clare Burrage , Alan Cutforth , Adam Moss , Thomas Vincent

We use properties of void populations identified in N-body simulations to forecast the ability of upcoming galaxy surveys to differentiate models of f(R) gravity from \Lambda CDM cosmology. We analyze simulations designed to mimic the…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 Paul Zivick , P. M. Sutter

An analysis of voids using cosmological N-body simulations of cold dark matter models is presented. It employs a robust statistics of voids, that was recently applied to discriminate between data from the Las Campanas Redshift Survey and…

Astrophysics · Physics 2009-11-07 S. Arbabi-Bidgoli , V. Mueller

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

The Vainshtein mechanism, present in many models of gravity, is very effective at screening dark matter halos such that the fifth force is negligible and general relativity is recovered within their Vainshtein radii. Vainshtein screening is…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-21 B. Falck , Kazuya Koyama , Gong-bo Zhao , M. Cautun

We model the chameleon effect on cosmological statistics for the modified gravity f(R) model of cosmic acceleration. The chameleon effect, required to make the model compatible with local tests of gravity, reduces force enhancement as a…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-07 Yin Li , Wayne Hu

Cosmic voids provide low-density environments where the scalar fifth force predicted by $f(R)$ modified gravity can be weakly screened. We present a semi-analytical calculation of the monopole, dipole, and quadrupole of the void-galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-19 Yue Nan
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