Séance du 4 mai 2018

Lieu: IHP, salle 201.

11:00 Peng Zhou (Northwestern)
Lagrangian skeleton of affine hypersurface in (C*)^n
Abstract: Let W: (C*)^n -> C be a Laurent polynomial in $n$ variables, and let H be a generic smooth fiber of W. Previously, Ruddat-Sibilla-Treumann-Zaslow give a combinatorial recipe for a skeleton for H. In this paper, we show that for a suitable exact symplectic structure on H, the RSTZ-skeleton can be realized as the Liouville Lagrangian skeleton. This is based on work https://arxiv.org/abs/1803.00320 

14:15 Marc Kegel (Köln)
The knot complement problem for Legendrian and transverse knots
Abstract: The famous knot complement theorem by Gordon and Luecke states that two knots in the 3-sphere are equivalent if and only if their complements are homeomorphic. In this talk I want to discuss the same question for Legendrian and transverse knots and links in contact 3-manifolds. The main results are that Legendrian as well as transverse knots in the tight contact 3-sphere are equivalent if and only if their exteriors are contactomorphic.  

16:00 Thomas Vogel (München)
Rigidity results for overtwisted contact structures
Abstract: We describe the classification of Legendrian unknots in overtwisted contact structures on S^3. This can be used to determine the contact mappingclass group for overtwisted contact structures on S^3.