Seminar series
Date
Tue, 14 Oct 2014
15:45
15:45
Location
L4
Speaker
Georgios Rizell
Organisation
Cambridge
Using the fact that certain exotic spheres do not admit Lagrangian embeddings into $T^*{\mathcal S}^{n+1}$, as proven by Abouzaid and Ekholm-Smith, we produce non-trivial homotopy classes of the group of compactly supported symplectomorphisms of $T^*{\mathcal S}^n$. In particular, we show that the Hamiltonian isotopy class of the symplectic Dehn twist depends on the parametrisation used in the construction. Related results are also obtained for $T^*({\mathcal S}^n \times {\mathcal S}^1)$.
Joint work with Jonny Evans.