Active Chiral Membranes: Odd Mechanics, Spontaneous Flows and Shape Instabilities #

Sami Al-Izzi, Gareth Alexander

11:30 Monday in 4Q08.

Part of the Analysis of continuum mechanics session.

Abstract #

We describe the mechanics of active fluid membranes in coordinate-free, geometric form, with particular focus on chiral, or odd, contributions to the stress. These generate tangential forces in response to gradients of mean curvature that are directed along contours of constant mean curvature and, as a result, necessarily induce tangential membrane flows. When the normal viscous force amplifies perturbations the membrane shape can become linearly unstable. We describe examples for membranes tubes and helicoids.