Haim Diamant (Tel Aviv University)

Unlike symmetric particles such as spheres and rods, an asymmetric object sedimenting through a viscous fluid at zero Reynolds number usually shows an anisotropic or chiral response to the force.

We will discuss the effect of such a response on the hydrodynamic interaction between two particles. We will show the profound implications of these interactions for  the collective sedimentation of many particles. The tendency of asymmetric particles to deviate from the flow lines produced by the others either suppresses or enhances density fluctuations, resulting, respectively, in hyperuniform or unstable structures. Some of the conclusions are supported by recent experiments and a simple simulation.