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Hofer's diameter and Lagrangian intersections

Leonid Polterovich
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Abstract

We prove that the group of Hamiltonian diffeomorphisms of the 2-sphere has infinite diameter with respect to Hofer's metric. Our approach is based on the theory of Lagrangian intersections.

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Leonid Polterovich. 1998-01-12. Hofer's diameter and Lagrangian intersections. https://arxiv.org/abs/math/9801054

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