Macroscopic limits of active matter systems

Active matter systems consist of large collections of self-propelled particles and arise in a wide range of biological and physical contexts, including bird flocks, fish schools, and bacterial suspensions. Unlike passive systems, such particles can exhibit phase separation even in the absence of attractive interactions. In this talk, the speaker will introduce stochastic particle models for active matter, focusing on systems of interacting active Brownian particles subject to purely repulsive forces. Then, the speaker will discuss several approaches to derive macroscopic descriptions as partial differential equations. Finally, the speaker will present results on the stability and analytical properties of one such macroscopic model.