B. Bose, A. S. Gupta, B. Fiorini, G. Brando, F. Hassani, T. Baker, L. Lombriser, B. Li, C. Ruan, C. Hernández-Aguayo, L. Atayde, N. Frusciante
Abstract
Testing gravity and the concordance model of cosmology, Λ CDM, at large scales is a key goal of this decade's largest galaxy surveys. Here we present a comparative study of dark matter power spectrum predictions from different numerical codes in the context of three popular theories of gravity that induce scale-independent modifications to the linear growth of structure: nDGP, Cubic Galileon, and K-mouflage. In particular, we compare the predictions from N-body simulations solving the full scalar field equation, two N-body codes with approximate time integration schemes, a parametrized modified N-body implementation, and the analytic halo model reaction approach. We find the modification to the Λ CDM spectrum is in 2 per cent agreement at z≤1 and k≤1 hMpc−1 over all gravitational models and codes, in accordance with many previous studies, indicating these modelling approaches are robust enough to be used in forthcoming survey analyses under appropriate scale cuts. We further make public the new code implementations presented, specifically the halo model reaction K-mouflage implementation and the relativistic Cubic Galileon implementation.
Keywords
methods: numerical, cosmology: large-scale structure of Universe, cosmology: theory
Monthly Notices of the Royal Astronomical Society
Volume 536, Issue 1, Page 664
2024 December
