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Related papers: Density profiles and voids in modified gravity mod…

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The N-body dark matter (DM) simulations point that DM density profiles, e.g. the NFW halo, should be cuspy in its center, but observations disfavour this kind of DM profile. Here we consider whether the observed rotation curves "close" to…

Astrophysics of Galaxies · Physics 2014-11-04 Davi C. Rodrigues , Paulo L. de Oliveira , Julio C. Fabris , Gianfranco Gentile

The comparison between dynamical mass and lensing mass provides a targeted test for a wide range of modified gravity models. In our previous paper we showed, through numerical simulations, that the measurement of the line-of-sight velocity…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-05 Tsz Yan Lam , Fabian Schmidt , Takahiro Nishimichi , Masahiro Takada

We study the effects of mass and force resolution on the density profiles of galaxy-size Cold Dark Matter (CDM) halos in a flat, low-density cosmological model with vacuum energy. We show thatalthough increasing the mass and force…

Astrophysics · Physics 2008-11-26 Anatoly Klypin , Andrey V. Kravtsov , James Bullock , Joel Primack

Cosmic voids are a promising environment to characterize neutrino-induced effects on the large-scale distribution of matter in the universe. We perform a comprehensive numerical study of the statistical properties of voids, identified both…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-18 Elena Massara , Francisco Villaescusa-Navarro , Matteo Viel , P. M. Sutter

Modifications to General Relativity (GR) often incorporate screening mechanisms in order to remain compatible with existing tests of gravity. The screening is less efficient in underdense regions, which suggests that cosmic voids can be a…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-06 Christopher T. Davies , Marius Cautun , Baojiu Li

The statistics of dark matter halos is an essential component of understanding the nonlinear evolution in modified gravity cosmology. Based on a series of modified gravity N-body simulations, we investigate the halo mass function,…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-21 Youcai Zhang , Pengjie Zhang , Xiaohu Yang , Weiguang Cui

Dynamical mass discrepancies in galaxies have two possible explanations: the existence of large amounts of dark matter or the breakdown of Newtonian gravity. True dark matter halos of galaxies could differ in several respects from apparent…

Astrophysics · Physics 2007-05-23 J. A. Sellwood , A. Kosowsky

Galaxies in cosmic voids have been reported with properties related to a delayed evolution with respect to the Universe in general. These characteristics reflect the interaction of galaxies with the environment. However, it is not clear the…

Constraints on dark matter halo masses from weak gravitational lensing can be improved significantly by using additional information about the morphology of their density distribution, leading to tighter cosmological constraints derived…

Modified gravitational forces in models that seek to explain cosmic acceleration without dark energy typically predict deviations in the abundance of massive dark matter halos. We conduct the first, simulation calibrated, cluster abundance…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-06 Fabian Schmidt , Alexey Vikhlinin , Wayne Hu

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

Modified Gravity (MG) scenarios have been advocated to account for the dark energy phenomenon in the universe. These models predict departures from General Relativity on large cosmic scales that can be tested through a variety of probes…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-12 P. S. Corasaniti , C. Giocoli , M. Baldi

As one of the most powerful probes of cosmological structure formation, the abundance of massive galaxy clusters is a sensitive probe of modifications to gravity on cosmological scales. In this paper, we present results from N-body…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Simone Ferraro , Fabian Schmidt , Wayne Hu

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 gravity theories have richer observational consequences for large-scale structure than conventional dark energy models, in that different observables are not described by a single growth factor even in the linear regime. We examine…

Astrophysics · Physics 2009-02-20 Bhuvnesh Jain , Pengjie Zhang

Our goal is to see how density waves of different scale combine to form voids between galaxy systems of various scale. We perform numerical simulations of structure formation in cubes of size 100 and 256 Mpc/h, with resolutions 256^3 and…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-13 J. Einasto , I. Suhhonenko , G. Hütsi , E. Saar , M. Einasto , L. J. Liivamägi , V. Müller , A. A. Starobinsky , E. Tago , E. Tempel

Within the Halo Model of large scale structure, all matter is contained in dark matter halos. This simple yet powerful framework has been broadly applied to multiple data sets and enriched our comprehension of how matter is distributed in…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-25 Rodrigo Voivodic , Henrique Rubira , Marcos Lima

We study lensing by voids in Cubic Galileon and Nonlocal gravity cosmologies, which are examples of theories of gravity that modify the lensing potential. We find voids in the dark matter and halo density fields of N-body simulations and…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-15 Alexandre Barreira , Marius Cautun , Baojiu Li , Carlton Baugh , Silvia Pascoli

We pioneer the black hole mass gap as a powerful new tool for constraining modified gravity theories. These theories predict fifth forces that alter the structure and evolution of population-III stars, exacerbating the pair-instability.…

General Relativity and Quantum Cosmology · Physics 2020-12-16 Maria C. Straight , Jeremy Sakstein , Eric J. Baxter

We study the formation and evolution of voids in the dark matter distribution using various simulations of the popular $\Lambda$ Cold Dark Matter cosmogony. We identify voids by requiring them to be regions of space with a mean overdensity…

Astrophysics · Physics 2009-11-10 Joerg M. Colberg , Ravi K. Sheth , Antonaldo Diaferio , Liang Gao , Naoki Yoshida