# Séminaires : Séminaire Groupes, Représentations et Géométrie

 Equipe(s) : gr, Responsables : A. Brochier, O. Brunat, J.-Y. Charbonnel, O. Dudas, E. Letellier, D. Juteau, M. Varagnolo, E. Vasserot Email des responsables : Adrien Brochier , Olivier Brunat , Jean-Yves Charbonnel , Olivier Dudas , Emmanuel Letellier , Daniel Juteau , Michela Varagnolo , Eric Vasserot Salle : salle 2015, 2em étage, Adresse : Sophie Germain Description

 Orateur(s) Peter SAMUELSON - University of Edinburgh, Titre Hall algebras and the Fukaya category Date 30/03/2018 Horaire 10:30 à 11:30 Diffusion Résume The Hall algebra of an abelian (or triangulated) category A has a basis given by isomorphism classes of objects, and multiplication given by counting extensions.'' The Fukaya category of a (real) symplectic manifold M has objects given by Lagrangians in M, and morphism spaces given by intersections of Lagrangians. In the first half of the talk we give a brief overview of some recent results about Hall algebras of categories of coherent sheaves over (algebraic) curves, and then recall a concrete description of the Fukaya category of a surface due to Haiden, Katzarkov, and Kontsevich. In the second half of the talk we use work of Hernandez and Leclerc to give a precise description of the (derived) Hall algebra of the Fukaya category of a disk, and give a conjectural description of the Hall algebra for most'' surfaces. (This is joint work with Ben Cooper.) Salle salle 2015, 2em étage, Adresse Sophie Germain