Coadjoint orbits of symplectic diffeomorphisms of surfaces and ideal hydrodynamics
نویسندگان
چکیده
We give a classification of generic coadjoint orbits for the groups of symplectomorphisms and Hamiltonian diffeomorphisms of closed symplectic surfaces. We also classify simple Morse functions on symplectic surfaces with respect to actions of those groups. This gives an answer to V.Arnold’s problem on invariants of generic isovorticed fields for 2D ideal fluids.
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