Workshop on Contact and Symplectic Topology

(with a focus on open problems)

September 12-15, 2011, Lodz (Poland)

Organizers: Michael Entov (Technion, Israel), Aleksy Tralle (Univ. of Warmia and Mazury, Poland)





General information:

The workshop will focus on open problems in contact and symplectic topology. It will be held on September 12-15, 2011 in Lodz, Poland, as a special section of the Joint Meeting of the Israel Mathematical Union and the Polish Mathematical Society and is sponsored by CAST - Contact and Symplectic Topology (a research network supported by the European Science Foundation).


IMPORTANT ANNOUNCEMENTS:


The list of participants


Program:

Schedule:

Monday, September 12

14:30-15:20 Usher
15:30-16:00 Shelukhin
16:00-16:30 COFFEE BREAK
16:30-17:20 Welschinger
17:30-18:20 Abouzaid
18:30-19:30 Fukaya

Tuesday, September 13

8:30 - 9:15 Niederkrueger
9:20 - 10:00 Gal

14:00-14:50 Ostrover
15:00-16:00 Lalonde
16:00-16:30 COFFEE BREAK
16:30-17:20 Hind
17:30-18:30 Abreu

Wednesday, September 14

8:30 - 9:00 Pedroza
9:10 - 10:00 Ono

Thursday, September 15

8:30-9:20 Kedra
14:00-14:50 Savelyev
15:00-15:50 Frauenfelder

Titles and abstracts:

  • Mohammed Abouzaid (MIT, USA)
    Title: Generating Fukaya categories
    Abstract: I will discuss a geometric context wherein one can prove that a certain collection of Lagrangians generate the Fukaya category, and develop some applications to the study of Lagrangian embeddings.

  • Miguel Abreu (IST, Portugal)
    Title: Remarks on Lagrangian Intersections in Toric Manifolds
    Abstract: I will show how to get a lot of "mileage" out of applying two simple geometric remarks to questions on Lagrangian intersections in toric manifolds. Joint work with Leonardo Macarini.

  • Urs Frauenfelder (Seoul National U., South Korea)
    Title: Bubbles and Onis
    Abstract: In joint work with Peter Albers we study a version of Rabinowitz action functional on very negative line bundles over a symplectic manifold. If the line bundle is very negative bubbles disappear. I explain how bubbles transform into oni's - a new PDE problem - and how one can fight against oni's . Then I explain how one can use this approach to attack Arnold's conjecture in the presence of torsion.

  • Kenji Fukaya (U. of Kyoto, Japan)
    Title: Deformation of surface singularity and Lagrangian Floer homology
    Abstract: In this talk I explain calculation of Floer homology of some Lagrangian tori in a symplectic manifold obtained by deforming orbifold singularity in toric surface. Especially I explain the example of a cubic surface. The calculation implies that the second bounded cohomology of the universal cover of its group of Hamiltonian diffeomorphisms is infinite-dimensional.

  • Swiatosław Gal (U. Wien, Austria)
    Title: dK(g):=g*α-α
    Abstract: Let G be an abstract group acting on a space X. Let g be an element of G. It is a vague, but interesting problem what could be deduced about group properties of g∈G from the dynamical properties of the action of g.
    In the talk we would construct a natural cocycle on a class of groups of homeomorphisms. This class includes, among others, groups of Hamiltonian diffeomorphisms of symplectically aspherical manifolds and groups of homeomorphisms of a space preserving given first cohomology class.
    We will use this cocycle to prove that certain elements cannot be distorted (they have nonzero translation length).
    As a side remark we will deduce that fundamental group of symplectically hyperbolic manifold cannot be amenable.
    This is a joint work with Jarek Kędra from U. of Aberdeen.

  • Richard Hind (U. of Notre Dame, USA)
    Title: Symplectic embedding of ellipsoids
    Abstract: We will discuss some constructions and obstructions to embedding ellipsoids in dimension greater than four. There are many open questions, but optimal results are known for certain classes of embeddings into balls and cylinders. This is joint work with Olga Buse and Ely Kerman.

  • Jarek Kędra (U. of Aberdeen, UK, and U. of Szczecin, Poland)
    Title: Quasi-isometric embeddings into diffeomorphism groups
    Abstract: Let M be a smooth compact oriented manifold of dimension at least two endowed with a volume form. Assuming certain conditions on the fundamental group of M I will construct quasi-isometric embeddings of either free abelian or direct products of non-abelian free groups into the group of volume preserving diffeomorphisms of M equipped with the L^p metric induced by a Riemannian metric on M.
    This is a joint work with Michael Brandenbursky.

  • François Lalonde (U. of Montreal, Canada)
    Title: Moduli spaces in cluster homology

  • Klaus Niederkrueger (U. Paul Sabatier - Toulouse III, France)
    Title: Weak fillability for higher dimensional contact manifolds
    Abstract: In $3$--dimensional contact topology there is a well-known hierarchy of definitions of fillability, including Stein, exact, strong, and weak symplectic fillings. These notions have been studied extensively yielding examples that show that they all differ.
    In higher dimensional contact topology similar definitions exist, but the proposed definition for weak fillings has been known for at least 20 years to be equivalent to the strong fillability.
    In this talk, I will propose a new definition for weak fillability, and try to justify it, by showing that every contact structure can be modified into one that is not weakly fillable (with our definition), and that there exist contact manifolds that are weakly, but not strongly fillable.
    This is a joint work with Patrick Massot and Chris Wendl.

  • Kaoru Ono (Hokkaido U., Japan)
    Title: Displacement energy of Lagrangian submanifolds and the torsion of Lagrangian Floer cohomology
    Abstract: Yuri Chekanov gave a lower bound for the displacement energy of a Lagrangian submanifold using Floer theoretical argument. In this talk, I will give a lower bound for the displacement energy of an unobstructed Lagrangian submanifold using the torsion information of Lagrangian Floer cohomology with $\Lambda_0$-coefficients. As examples, we discuss the displacement energy of Lagrangian torus fibers in compact toric manifolds. This talk is based on a joint work with K. Fukaya, Y.-G. Oh, H. Ohta.

  • Yaron Ostrover (Tel-Aviv U., Israel)
    Title: On the uniqueness of Hofer's geometry
    Abstract: In this talk we address the question whether Hofer's metric is unique among the Finsler-type bi-invariant metrics on the group of Hamiltonian diffeomorphisms. The talk is based on a recent joint work with Lev Buhovsky.

  • Andrés Pedroza (U. de Colima, Mexico)
    Title: Bounded Hamiltonian diffeomorphisms
    Abstract: We prove the bounded isometry conjecture of F.Lalonde and L.Polterovich for a special class of closed symplectic manifolds. The class of symplectic manifolds are those whose degree-one cohomology group is generated by embedded punctured tori.

  • Yasha Savelyev (CRM-Montreal, Canada)
    Title: Quantum corrections to Hofer length and diameter
    Abstract: We discuss a Floer theoretic, variationally complete length functional on the path spaces of Ham(M,\omega), inducing the spectral norm. The main motivation for this is to give an abstract approach to injectivity radius problem in Hofer geometry, and we will spend some time discussing this.

  • Egor Shelukhin (Tel-Aviv U., Israel)
    Title: A quasimorphism for every symplectic manifold
    Abstract: Using the action of the Hamiltonian group on the space of compatible almost complex structures we construct a quasimorphism on its universal cover. Key notions in the construction include equivariant moment maps, the Action homomorphism and bounded cocycles given by integration over geodesic triangles.

  • Michael Usher (U. of Georgia, USA)
    Title: Hofer's metrics and the boundary depth
    Abstract: I will show how to use a Floer-theoretic quantity called the boundary depth to prove infinite diameter (and indeed the existence of infinite-dimensional quasi-isometrically embedded normed vector spaces) for Hofer's metrics on groups of Hamiltonian diffeomorphisms or spaces of Lagrangian submanifolds in a variety of cases.

  • Jean-Yves Welschinger (U. Lyon 1, France)
    Title: What is the total Betti number of a random real hypersurface?
    Abstract: I will estimate from above the expected total Betti number of a random real hypersurface of a smooth real projective manifold. This upper bound is based on the equirepartition of critical points of a real Lefschetz pencil restricted to such a hypersurface. The proofs involve Ho"rmander's peak sections and a formula of Poincare'-Martinelli, it is a joint work with Damien Gayet.