On the autonomous norm on the group of Hamiltonian diffeomorphisms of a surface

Symplectic geometry and topology

08 October 15:30 - 16:30

Jaroslaw Kedra - University of Aberdeen

Every Hamiltonian diffeomorphism F is a product of autonomous ones. The smallest number of them is, by definition, the autonomous norm of F. I will sketch a proof the fact that the autonomous norm of Ham(M,w), where M is a surface, is unbounded. The main point of the argument is to construct a suitable Lipschitz function Ham(M,w) --> R. This will be done using braids and quasimorphisms.
Tobias Ekholm,
Uppsala University
Yakov Eliashberg
Stanford University
Lenhard Ng
Duke University
Ivan Smith
University of Cambridge


Tobias Ekholm


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