SEMINAR ON SYMPLECTIC AND CONTACT GEOMETRY

Université Libre de Bruxelles

First Semester 2007-2008

Monday 14:00-15:00

Room 2.NO.906

Monday, October 8th

Brussels-Cologne joint seminar, Universität zu Köln
Math building (Weyertal 86-90), 2nd floor (Großer Hörsall).
Directions

  
13:00 Jesús Gonzalo (Universidad AutónoMa de Madrid)
A dynamical characterization of contact circles
14:30 Sílvia Anjos (Instituto Superior Técnico, Lisboa)
The topology of the space of symplectic balls in S2 × S2

Monday, October 15th

Baptiste Chantraine (ULB)
Lagrangian cobordism of legendrian knots

Monday, October 22nd

Mathias Zessin (ULB)
Toupies intégrables et de contact

Monday, November 5th

Felix Schlenk (ULB)
Entropie topologique positive pour flot de Reeb

Monday, November 12th

Gonzalo Contreras (CIMAT)
Elliptic closed geodesics on the sphere

Monday, November 19th

Joel Fine (ULB)
Symplectic Calabi-Yaus via connections

This is joint work with Dmitri Panov. Given an SO(3)-bundle with connection the associated 2-sphere bundle carries a natural closed 2-form. Asking that this form be symplectic gives a curvature inequality first studied by Reznikov. We consider the case when the base has dimension four. In this case the inequality says simply that the conneciton has non-zero holonomy on every two-plane. A key point is that such connections carry a sign, with plus giving a symplectic Fano manifold and minus a symplectic Calabi-Yau. Examples can be found using Riemannian metrics and in this way many non-Kahler symplectic Calabi-Yaus can be produced. If there is time I will exlpain how pseudoholomorphic curves in the Calabi-Yau correspond to minimal surfaces in the four-manifold and how standard facts about pseudoholomorphic curves give new results for minimal surfaces.

Friday, November 23rd

Brussels-Cologne joint seminar, Université Libre de Bruxelles
NO building (Campus Plaine), 5th floor (Salle Solvay).
Directions

  
14:15 Rémi Leclercq (Max Planck Institute, Leipzig)
Spectral invariants for Lagrangian intersection Floer theory
15:45 Emmanuel Ferrand (Université Pierre et Marie Curie, Paris)
Positive isotopies of legendrian embeddings
Une structure de contact coorientée sur une variété de dimension impaire est un champ d'hyperplans maximalement non-intégrable, globablement défini comme le champ des noyaux d'une 1-forme de contact α. Un chemin de difféomorphismes préservant la structure de contact est dit positif si son générateur infinitésimal Xt vérifie α(Xt)>0, c'est à dire si le vecteur Xt pointe dans le demi-espace déterminé par la coorientation de l'hyperplan. Un exemple typique de cette situation est le flot géodésique, défini sur le fibré tangent unitaire d'une variété riemannienne. Après avoir motivé par des exemples cette problématique, mon but sera d'exhiber des obstructions à l'existence de lacets positifs. Il s'agit d'un travail commun avec Petya Pushkar et Vincent Colin.

Monday, December 3rd

Frédéric Bourgeois (ULB)
Contact homology and legendrian surgery

Saturday, December 8th

Brussels-Cologne joint seminar, Universität zu Köln
Math building (Weyertal 86-90), 2nd floor (Großer Hörsall).
Directions

  
14:15 Patrick Popescu-Pampu (Paris VII)
On the cohomology of Stein and Milnor fillable manifolds
15:45 Patrick Massot (ENS Lyon)
Geodesible contact structures on 3-manifolds

Monday, December 10th

Mélanie Bertelson (ULB)
How to foliate the Künneth formula ?

Previous Semesters :
First Semester 2005-2006
Second Semester 2005-2006
First Semester 2006-2007
Second Semester 2006-2007
Next Semesters :
Second Semester 2007-2008
First Semester 2008-2009

Maintained by Frédéric Bourgeois.