Evolution of the cluster abundance in non-Gaussian models

We carry out N-body simulations of several non-Gaussian structure formation models, including Peebles' isocurvature cold dark matter model, cosmic str ing models, and a model with primordial voids. We compare the evolution of the cluster mass function in these simulations with that predicted by a mod ified version of the Press-Schechter formalism. We find that the Press-Sche chter formula can accurately fit the cluster evolution over a wide range of redshifts for all of the models considered, with typical errors in the mas s function of less than 25 per cent, considerably smaller than the amount b y which predictions for different models may differ. This work demonstrates that the Press-Schechter formalism can be used to place strong model-indep endent constraints on non-Gaussianity in the Universe.