Theory of anomalous diffusion in colloidal monolayers on a spherical interface.

A planar colloidal monolayer exhibits collective anomalous diffusion due to the effect of the hydrodynamic interactions. We investigate how this behavior is affected by the curvature of the monolayer when it resides on the interface of a spherical droplet. It is found that the characteristic times of the dynamics still exhibit the same anomalous scaling as in the planar case. The spatial distribution, however, shows a difference due to the relevance of the radius of the droplet. Since this is both a global magnitude, i.e., pertaining the spatial extent of the droplet, and a local one, i.e., the radius of curvature, the question remains open as to which of these two features actually dominates.