Non-Relativistic Spacetimes with Cosmological Constant
  Recent data on supernovae favor high values of the cosmological constant. Spacetimes with a cosmological constant have non-relativistic kinematics quite different from Galilean kinematics. De Sitter spacetimes, vacuum solutions of Einstein's equations with a cosmological constant, reduce in the non-relativistic limit to Newton-Hooke spacetimes, which are non-metric homogeneous spacetimes with non-vanishing curvature. The whole non-relativistic kinematics would then be modified, with possible consequences to cosmology, and in particular to the missing-mass problem. 
R. Aldrovandi, A.L. Barbosa, L.C.B. Crispino and J.G. Pereira (IFT -   UNESP / Sao Paulo)