Christian Blohmann: Cohomological zero locus of Noether currents and reduction

Abstract

 In my second talk, I will review the obstruction theory for hamiltonian actions on symplectic manifolds and explain how it generalizes to the multisymplectic setting. This will lead to the definition of the cohomological zero locus of the \(L_\infty\)-Noether current map in Lagrangian Field Theory. The zero locus can equivalently be described by the vanishing of all Noether charges and a coisotropicity condition. Finally, I will show that the zero locus, including its singular strata, is invariant under the symmetry group action. This is joint work with Janina Bernardy.