Physics of colloids in action

This talk will describe new results on the properties of colloidal crystals, both on their solidification and on their melting.  It will describe how hard-sphere like colloids crystallize, and will explore the huge discrepancy between the nucleation rates predicted by theory and measured in simulation and those measured experimentally.  The discrepancy can be as large as 150 orders of magnitude!  A simple modification to the theory, suggested by experiment, is able to account for this behavior and to rectify the discrepancy.  It will also describe how perfect colloidal crystals, formed in a Wigner lattice, melt.  Since there are no grain boundaries for the crystals, melting occurs in a different fashion, one that seems to have some second order character to it.