Prof. Alberto Fernandez-Nieves, University of Barcelona and Institució Catalana de Recerca i Estudis Avançats
Barcelona

"Active nematic defects in flat and curved space"

Abstract: I will discuss results with active nematics confined to toroidal and flat space. I will first describe how curvature affects defect arrangement on tori, showing that despite the intrinsic activity and out-of-equilibrium character of the system, there are still remnants of the expected curvature-induced defect unbinding predicted for nematics in their ground state. Activity, however, augments the behavior leading to unexpected defect distributions. I will then focus on defect orientation and show that on flat space, we find short-range orientational, both "ferromagnetic" and "antiferromagnetic", correlations without long-range orientational order.