Cage Effect, Local Anisotropies, and Dynamic Heterogeneities at the Glass Transition: A Computer Study of Hard Spheres

Computer simulations of a hard sphere system close to the glass transition are presented. From three-time correlations, we obtain information about the single-particle dynamics on all relevant time scales, including the presence of dynamic heterogeneities. A detailed picture of the cage effect in the $\beta$ regime is obtained, yielding information about shape, size, and relaxation properties of the effective cage. Pronounced anisotropic dynamics is mainly observed in the $\beta$ regime.