Structure grows differently under different cosmological models, due to:

- Different mass density (Omega_m)
- Different expansion history (Omega_m, Omega_L, H0)
- Different ages (Omega_m, Omega_L, H0)
- Different fluctuation spectra (n)
- Different dark matter models (HDM, CDM, WDM [MDM, SIDM.....])

Simulations:

Can be compared quantitatively to measures of 2ptCF, but need to worry about galaxy biasing effects.

How else can we use observed structure to constrain cosmological models?

- Using Clusters
- Cluster Growth Models (from Borgani+ 03)
- Cluster Growth Models+Obs (from Bahcall+ 97)
- MS1054-0321