Relativistic rotation curve for cosmological structures
  Using a general relativistic exact model for spherical structures in a
cosmological background, we have put forward an algorithm to calculate the test
particle geodesics within such cosmological structures in order to obtain the
velocity profile of stars or galaxies. The rotation curve thus obtained is
based on a density profile and is independent of any mass definition which is
not unique in general relativity. It is then shown that this general
relativistic rotation curves for a toy model and a NFW density profile are
almost identical to the corresponding Newtonian one, although the general
relativistic masses may be quite different.
