2001ApJ...550...87G

In this paper, we apply the perturbative least-action method to model the Local Group of galaxies for various cosmological models. Our models suggest that the classical timing argument overestimates the true mass of the Local Group system. We further show that although the galaxy masses are theoretically good discriminators of Ω_M given some observed Milky Way and M31 separation and radial velocity, current estimates of the masses are insufficient to make any cosmological claims.