Deems Ioratim-Uba

Dynamic membranes via non-reciprocity

In this talk, I will introduce the non-reciprocal Cahn-Hilliard (NRCH) model for a binary fluid mixture and explain my work extending this to curved surfaces. The NRCH model breaks the interaction symmetry of the traditional Cahn-Hilliard model, where the force felt by one species due to the other is equal and opposite to the force it exerts. For example, species A can be attracted to B while B is repelled by A, resulting in A chasing B. Even the minimal version of the NRCH model has rich behaviour including multi-stable travelling waves and topological defects. When coupled to an elastic membrane such that the two species locally change the mean curvature of the membrane, the non-reciprocity generates travelling membrane undulations and other complex patterns.