SoftBio Theory Seminar: Active Matter - A treasure trove of novel universality classes

A hallmark of living organisms is their ability to move around in their environments. In the fluid state, e.g., when the motile agents can exchange neighbours freely, the equations of motion that describes the dynamics of such active system are called the Toner-Tu (TT) equations. The TT equations govern active fluids the same way that the Navier-Stokes equations govern simple fluids. Since the inception of the TT equations in 1995, dynamic renormalization group (DRG) analyses have led to the discovery of many universality classes (UC) that correspond to novel nonequilibrium states of matter (or phases) and critical phenomena. In this talk, I will first focus on the incompressible limit of the TT equations and elucidate the associate universal behaviour. I will then go beyond this incompressible limit and showcase the many new UC uncovered in recent years.