Cosmological Model Predictions for Weak Lensing: Linear and Nonlinear Regimes
Weak lensing by large-scale structure induces correlated ellipticities in the images of distant galaxies. The two-point correlation is determined by the matter power spectrum along the line of sight. We use the fully nonlinear evolution of the power spectrum to compute the predicted ellipticity correlation. We present results for di erent measures of the second moment for angular scales h ^1@3 and for alternative normalizations of the power spectrum, in order to explore the best strategy for constraining the cosmological parameters. Normalizing to observed cluster abundance, the rms amplitude of ellipticity within a 15@ radius is almost independent of the cosmological model, with being the median ^0.01z s 0.6, z s redshift of background galaxies.