Topological patterns in active liquid crystals

Active materials are composed of interacting entities that are individually powered and exhibit rich emergent behavior at larges scales. For instance, a dense swarm of bacteria can behave collectively as a living liquid crystal, self-organize in complex regular patterns, exhibit turbulent-like motion, or ‘freeze’ into a solid-like biofilm. In this talk I will discuss theoretical work on active liquid crystals confined to two-dimensional planar and curved interfaces. I will show how the topology of the environment can create new types of collective behaviors in these systems, including complex dynamical patterns, self-sustained oscillations and topologically protected sound waves.