Simulating galaxy formation in f(R) modified gravity: matter, halo, and galaxy statistics
Abstract
We present an analysis of the matter, halo, and galaxy clustering in f(R)gravity employing the SHYBONE fullphysics hydrodynamical simulation suite. Our analysis focuses on the interplay between baryonic feedback and f(R)gravity in the matter power spectrum, the matter and halo correlation functions, the halo and galaxyhosthalo mass function, the subhalo and satellitegalaxy count, and the correlation function of the stars in our simulations. Our studies of the matter power spectrum in fullphysics simulations in f(R)gravity show that it will be very difficult to derive accurate fitting formulae for the power spectrum enhancement in f(R)gravity which include baryonic effects. We find that the enhancement of the halo mass function due to f(R)gravity and its suppression due to feedback effects do not show significant backreaction effects and can thus be estimated from independent general relativityhydro and f(R) dark matter only simulations. Our simulations furthermore show that the number of subhaloes and satellitegalaxies per halo is not significantly affected by f(R)gravity. Lowmass haloes are nevertheless more likely to be populated by galaxies in f(R)gravity. This suppresses the clustering of stars and the galaxy correlation function in the theory compared to standard cosmology.
 Publication:

Monthly Notices of the Royal Astronomical Society
 Pub Date:
 December 2019
 DOI:
 10.1093/mnras/stz2690
 arXiv:
 arXiv:1907.02980
 Bibcode:
 2019MNRAS.490.2507A
 Keywords:

 methods: numerical;
 cosmology: theory;
 Astrophysics  Cosmology and Nongalactic Astrophysics;
 General Relativity and Quantum Cosmology
 EPrint:
 15 pages, 12 figures, accepted for publication in MNRAS