1. Modified gravity N-body code comparison project
- Author
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Ewald Puchwein, Claudio Llinares, Alexandre Barreira, Christian Arnold, Fabian Schmidt, Gong-Bo Zhao, Marco Baldi, Wojciech A. Hellwing, Bridget Falck, Hans A. Winther, Baojiu Li, David F. Mota, Robert E. Smith, Sownak Bose, Kazuya Koyama, Winther, Hans A, Schmidt, Fabian, Barreira, Alexandre, Arnold, Christian, Bose, Sownak, Llinares, Claudio, Baldi, Marco, Falck, Bridget, Hellwing, Wojciech A., Koyama, Kazuya, Li, Baojiu, Mota, David F., Puchwein, Ewald, Smith, Robert E., and Zhao, Gong-Bo
- Subjects
Gravity (chemistry) ,Cosmology and Gravitation ,Cold dark matter ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Large-scale structure of Universe ,General relativity ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,General Relativity and Quantum Cosmology (gr-qc) ,General Relativity and Quantum Cosmology ,Many-body problem ,Quantum mechanics ,Limit (mathematics) ,Statistical physics ,STFC ,QB ,Physics ,Matter power spectrum ,RCUK ,Astronomy and Astrophysics ,Observable ,Space and Planetary Science ,astro-ph.CO ,Halo ,large-scale structure of Universe ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
Self-consistent ${\it N}$-body simulations of modified gravity models are a key ingredient to obtain rigorous constraints on deviations from General Relativity using large-scale structure observations. This paper provides the first detailed comparison of the results of different ${\it N}$-body codes for the $f(R)$, DGP, and Symmetron models, starting from the same initial conditions. We find that the fractional deviation of the matter power spectrum from $\Lambda$CDM agrees to better than $1\%$ up to $k \sim 5-10~h/{\rm Mpc}$ between the different codes. These codes are thus able to meet the stringent accuracy requirements of upcoming observational surveys. All codes are also in good agreement in their results for the velocity divergence power spectrum, halo abundances and halo profiles. We also test the quasi-static limit, which is employed in most modified gravity ${\it N}$-body codes, for the Symmetron model for which the most significant non-static effects among the models considered are expected. We conclude that this limit is a very good approximation for all of the observables considered here., Comment: 31 pages, 16 figures. Version to appear in MNRAS
- Published
- 2015