The central cusp of dark matter halos in galaxies and modified gravity models.
The N-body dark matter simulations point that dark matter density profiles (e.g., the Navaro-Frenk-White (NFW) halo) should be cuspy in its center, but observations disfavour this kind of dark matter profile. We consider whether the observed rotation curves close to the galactic centre can favour modified gravity models in comparison to the NFW halo, and how to systematically quantify such difference. In particular I will present a recent study based on a sample of 62 galaxies and consider two explicit non-Newtonian gravity models: MOND and a more recent approach called RGGR (in reference to Renormalization Group effects in General Relativity). We find that, even without assuming a correlation between the two NFW halo parameters, the latter two models can systematically derive better fits to the central parts of the galaxies.