English
Related papers

Related papers: Modified Gravity Spins Up Galactic Halos

200 papers

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

Viable modifications of gravity that may produce cosmic acceleration need to be screened in high-density regions such as the Solar System, where general relativity is well tested. Screening mechanisms also prevent strong anomalies in the…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-22 Lucas Lombriser , Fergus Simpson , Alexander Mead

We analyse the two-point and marked correlation functions of haloes and galaxies in three variants of the chameleon $f(R)$ gravity model using N-body simulations, and compare to a fiducial $\Lambda$CDM model based on general relativity…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-26 César Hernández-Aguayo , Carlton M. Baugh , Baojiu Li

We develop the general scheme for modified $f(R)$ gravity reconstruction from any realistic FRW cosmology. We formulate several versions of modified gravity compatible with Solar System tests where the following sequence of cosmological…

High Energy Physics - Theory · Physics 2008-11-26 Shin'ichi Nojiri , Sergei D. Odintsov

(Abridged) We report results of a series of non radiative N-body/SPH simulations in a LCDM cosmology. We find that the spin of the baryonic component is on average larger than that of the dark matter (DM) component and we find this effect…

Astrophysics · Physics 2009-11-10 Sanjib Sharma , Matthias Steinmetz

In this Letter, we investigate the environmental dependence of dark matter halos in theories that attempt to explain the accelerated expansion of the Universe by modifying general relativity (GR). Using high-resolution N-body simulations in…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-17 Gong-Bo Zhao , Baojiu Li , Kazuya Koyama

We propose a new framework for testing gravity using cluster observations, which aims to provide an unbiased constraint on modified gravity models from Sunyaev Zel'dovich (SZ) and X-ray cluster counts and the cluster gas fraction, among…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-10 Myles A. Mitchell , Jian-hua He , Christian Arnold , Baojiu Li

We investigate the co-evolution of the angular momentum of Milky Way-like galaxies, their circumgalactic gas, and their dark matter halos using zoom-in simulations from the Figuring Out Gas & Galaxies in Enzo (FOGGIE) suite. We examine how…

We use N-body simulations to study the statistics of massive halos and redshift space distortions for theories with a standard \Lambda CDM expansion history and a galileon-type scalar field. The extra scalar field increases the…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-30 Mark Wyman , Elise Jennings , Marcos Lima

We obtain more straightforwardly some features of dark matter distribution in the halos of galaxies by considering the spherically symmetric space-time, which satisfies the flat rotational curve condition, and the geometric equation of…

General Relativity and Quantum Cosmology · Physics 2021-09-21 Ugur Camci

We use a state-of-the-art semi-analytic model to study the size and the specific angular momentum of galaxies. Our model includes a specific treatment for the angular momentum exchange between different galactic components. Disk scale radii…

Astrophysics of Galaxies · Physics 2018-08-28 Anna Zoldan , Gabriella De Lucia , Lizhi Xie , Fabio Fontanot , Michaela Hirschmann

Galaxy formation in the current cosmological paradigm is a very complex process in which inflows, outflows, interactions and mergers are common events. These processes can redistribute the angular momentum content of baryons. Recent…

Astrophysics of Galaxies · Physics 2015-08-31 Susana Pedrosa , Patricia Tissera

We study the effect of magnetic fields on a simulated galaxy and its surrounding gaseous halo, or circumgalactic medium (CGM), within cosmological 'zoom-in' simulations of a Milky Way-mass galaxy as part of the 'Simulating the Universe with…

Modifications of general relativity provide an alternative explanation to dark energy for the observed acceleration of the universe. We review recent developments in modified gravity theories, focusing on higher dimensional approaches and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Bhuvnesh Jain , Justin Khoury

Modified gravity is one of the most promising candidates for explaining the current accelerating expansion of the Universe, and even its unification with the inflationary epoch. Nevertheless, the wide range of models capable to explain the…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Álvaro de la Cruz-Dombriz , Diego Sáez-Gómez

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

We use the IllustrisTNG300-ODM simulation to investigate the spin bias of low-mass halos and its connection to the strong clustering of ultra-diffuse galaxies (UDGs) reported by Zhang et al. (2025). By comparing two halo spin…

Astrophysics of Galaxies · Physics 2026-05-14 Qinglin Ma , Cheng Li , Yangyao Chen , Houjun Mo

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

The review is devoted to consideration of possible observational consequences of modified gravity theories, suggested for explanation of the contemporary accelerated expansion of the universe. The major attention is paid to F(R)-models. It…

General Relativity and Quantum Cosmology · Physics 2019-11-11 Elena Arbuzova

The angular momentum of galaxies controls the kinematics of their stars, which in turn drives observable quantities such as the apparent radius, the bulge fraction, and the alignment with other nearby structures. To show how angular…

Astrophysics of Galaxies · Physics 2022-10-12 Corentin Cadiou , Andrew Pontzen , Hiranya V. Peiris