Lieu: IHP, amphi Darboux
The seminar will take place in presence, but will be broadcasted via zoom
https://us02web.zoom.us/j/89445897442?pwd=QmVZWHBiM2Nwb09yUVJERnYrSHJrUT09
10:45 Agnès Gadbled (Orsay)
Floer-Novikov fundamental group for small flux isotopies.
Abstract: In Morse theory, the number of index 1 critical points of a
Morse function is bounded below by the minimal number of generators of
the fundamental group. In Floer theory, Barraud gave a bound on the
number of contractible 1-periodic orbits of a generic Hamiltonian thanks
to a Floer version of the fundamental group. In this talk I will speak
of the Novikov setting: how to define a Floer-Novikov fundamental group
as a Floer generalization of a Novikov fundamental group for 1-forms (we
previously defined with Barraud, Golovko and Lê) in order to get
information on symplectic (non Hamiltonian) isotopies. This is a joint
work with J.-F. Barraud.
14:00 Yann Rollin (Nantes)
Lagrangiens et symplectomorphismes vus comme des zéros d'applications moment.
Abstract:
Je présenterai deux constructions de variétés kählériennes, munies
d'actions Hamiltoniennes de tores de dimensions infinies. Dans le
premier exemple, les zéros de l'application moment peuvent être
interprétés comme des applications isotropes du tore T^2 dans R^4. Dans
le deuxième exemple, la construction est hyperkählériennes et les zéros
sont identifiés aux symplectomorphismes du tore T^4. Des flots
d'application moment peuvent être naturellement associés à ces
constructions et leur existence en temps court est garantie.
15:45 Pierre-Alexandre Arlove (Bochum)
Geodesics of norms on the contactomorphisms group of $R^2n\times S1$.
Abstract: The study of conjugation invariant norms on the group of
contactomorphisms of a contact manifold is relatively new in comparison
with the intensively studied Hofer norm on the group of Hamiltonian
symplectomorphisms. In this talk I will show that some particular paths
of contactomorphisms are geodesics for different norms on the identity
component of the group of compactly supported contactomorphisms of
$R^{2n}\times S1$ endowed with its standard contact structure. As a
corollary, I get a new proof of the unboundedness of these norms in this
context. Generating functions are the main technical tools used to get
this result.
Prochaines séances: 1er avril (A. Pirnapasov, G. Cazassus, ?), 13 mai (N. Porcelli, ?, ?), 10 juin (?, ?, ?)
Autre activité symplectique à Paris:
- Symplectic Zoominar (les vendredis hors symplectix à 15:15, heure de Paris)
