Speaker：Christian Blohmann ( MPIM, Bonn）
Time：16:00-17:30, October 15, 2019
Room：5506, the fifth teaching building
I will give a tour of the notion of hamiltonian actions from basic concepts to recent developments. In the first hour I will give a self contained review of the following topics: conserved quantities in classical mechanics; integrability; hamiltonian group actions; toric manifolds, Guillemin-Sternberg convexity theorem, Delzant reconstrucion; symplectic reduction; Bochner-Weinstein linearizaton at critical points. In the last half hour I will describe a recent generalization of hamiltonian actions to Lie algebroids and Lie groupoids, which is motivated by a study of the symmetries of General Relativity. This is joint work with Alan Weinstein.
