The Herman conjecture part1
Channel: Mauricio Garay
Date: 2022-04-07

The Herman invariant tori conjecture states that, assuming arithmetic conditions on the frequency;  the vinicity of an elliptic critical point contains a a positive measure set of invariant tori. Duco Van Straten gives an overview of the proof and then proceeds to the  definition of the Hamiltonian Normal Form. This normal form turns up to be more efficient than the usual Birkhoff normal form.