Endomorphisms and automorphisms of totally disconnected locally compact groups II

This lecture delves into the concept of flat groups of automorphisms, defining them as groups where certain subgroups are tidy for a given element. The instructor explores the properties of flat groups, such as minimization of certain functions, and their relation to polycyclic groups. The lecture also covers the notion of virtually flat groups and their characteristics, including being finitely generated and nilpotent. The presentation concludes with discussions on the invariance of certain subgroups under specific conditions.