Karl Franzens University Graz | Graz University of Technology | |
Colloids - Interfaces - 2d Cosmology in a Petri Dish In this talk we discuss the peculiar properties of colloidal particles of micrometer size trapped at fluid interfaces. One of them is the emergence of long-ranged, logarithmic capillary attractions, as in 2d Newtonian gravity. This implies that monolayers of particles are unstable and undergo a pseudogravitational collapse. Since the range of the logarithmic interaction can be screened at will, a rich phenomenology of the collapse is obtained which is associated with an interesting dynamic phase diagram. Further considerations on the hydrodynamic interactions induced by the solvent in such systems bring out a singularity in the wave-vector dependent diffusion coefficient which induces a considerable collapse speedup in the pseudogravitational system and anomalous diffusion in the fully screened system. |