|
|
|
ProgrammeLes exposés commenceront jeudi 4 décembre à 14h, et finiront vendredi 5 décembre à 15h. Mercredi 3 décembre 12h30 Déjeuner commun à Domus
9h30-12h30 Discussion / Collaboration
9h30-11h Olga Kravchenko (Lyon) et Vladimir Fock (Strasbourg)
Abstracts Léa Bittmann (Strasbourg), TBA Philippe Bonneau (Metz), « Lie 2-algebras infinitesimal actions and 2-plectic manifolds » We will give a definition of action of a Lie 2-algebra on a differential manifold generalising that of (infinitesimal) action of a Lie algebra. Then, modifying the usual (C. Rogers) notion of algebra of observables in multisymplectic geometry (and its Lie n-algebra structure), we will continue the generalisations to the notions of multisymplectic action, Hamiltonian action and comomentum map (Joint work with V. Chloup, A. Gammella and T. Wurzbacher)
Justine Fasquel (Dijon), « Inverting the quantum hamiltonian reduction » W-algebras form a rich family of vertex algebras, obtained from an affine vertex algebra via a sophisticated cohomological procedure known as quantum hamiltonian reduction. Although intricate, this reduction has the advantage of simplifying both the structure and the representation theory of W-algebras compared to that of the original affine vertex algebra. In this talk, I will discuss how to invert the procedure in order to reconstruct the more elaborated representation theory of the affine vertex algebra from that of its W-algebras. Olga Kravchenko (Lyon) et Vladimir Fock (Strasbourg), TBA
Julien Marché (ENS Paris), « Rigidity of representations of 3-manifold groups into SL_2(C) » By the geometrization program of Thurston-Perelman, most fundamental groups of 3-manifolds have rigid representations into SL_2(C).
In this talk we will discuss the situation of a general representation, in relation to character varieties and K-theory of the complex field.
Valentin Ovsienko (Reims), « q-rationals and dimers » The notion of q-deformed rational numbers was introduced in our work with Sophie Morier-Genoud. I will explain the relationships between q-rationals and the theory of dimer models. I will also discuss a natural q-deformation of the classical Markov numbers. The talk will be elementary and accessible to everyone. It is based on two recent preprints, arXiv:2507.19080 (jointly with Sam Evans, Sophie Morier-Genoud, and Perrine Jouteur) and arXiv:2510.16270. |
