Symplectic automorphisms of T^*S^2

Paul Seidel

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arXiv · math/9803084

Symplectic automorphisms of T^*S^2

Paul Seidel

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Abstract

Let M be the cotangent bundle of S^2, with the standard symplectic structure. By adapting an argument of Gromov we determine the weak homotopy type of the group S of those symplectic automorphisms of M which are trivial at infinity. It turns out that S is weakly homotopy equivalent to \Z. π_0(S) is generated by the class of the standard "generalized Dehn twist". As a consequence, we show that there are different connected components of S which lie in the same connected component of the corresponding group of diffeomorphisms.

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BibTeX RIS

Paul Seidel. 1998-03-19. Symplectic automorphisms of T^*S^2. https://arxiv.org/abs/math/9803084

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