Vendredi 8 décembre 2017

10h30 Sobhan Seyfaddini (P6)

Un contre-exemple C^0 à la conjecture d’Arnold.

Résumé : nous discutons la conjecture d'Arnold sur les points fixes de difféomorphismes, et homéomorphismes, hamiltoniens.

Vendredi 15 décembre 2017

10h30 Cédric Oms (UPC Barcelone)

Singular contact manifolds

Abstract: The study of singular symplectic manifolds was initiated by the work of Radko [1], who classified stable Poisson structures on surfaces. It was observed by Guillemin—Miranda—Pires [2] that stable Poisson structures can be treated as a generalization of symplectic geometry by extending the deRham complex. Since then, a lot has been done to study the geometry, dynamics and topology of those manifolds.

We will explore the odd-dimensional case of those manifolds in this talk by extending contact manifolds to the singular setting. We plan to give local normal forms and the relation to singular symplectic geometry.

This is joint work with Eva Miranda.

[1] O. Radko: A classification of topologically stable Poisson structures on a compact oriented surface, J. Symplectic Geometry, 1 (2002), no. 3, 523-542 

[2] V. Guillemin, E. Miranda, A. Pires: Symplectic and Poisson geometry of b-manifolds, Adv. Math. 264 (2014), 864-896