Testing Cosmogonic Models with Gravitational Lensing
  Gravitational lensing provides a strict test of cosmogonic models. Detailed numerical propagation of light rays through a universe having a distribution of inhomogeneities derived from the standard CDM (cold dark matter) scenario with the aid of massive, fully nonlinear computer simulations is used to test the model. It predicts that we should have seen far more widely split quasar images than have been found. These and other inconsistencies rule out the COBE normalized CDM model with $\Omega=1$ and $H_0=50$km/s/Mpc; but variants of this model might be constructed, which could pass the stringent tests provided by strong gravitational lensing. 
Joachim Wambsganss, Renyue Cen, Jeremiah P. Ostriker and Edwin L.   Turner