Big mapping class groups

par Prof. Ferrán Valdez (UNAM & Max Planck Institute)

lundi 19 nov. 2018, 16:30 → 17:45 Europe/Paris

Amphithéâtre Léon Motchane (IHES)

Mapping class groups associated to surfaces whose fundamental group is not finitely generated are called "big", and their study is linked to classical problems in dynamics. In this talk, we discuss some of the basic properties of big mapping class groups, their simplicial actions, and how these can be used to prove that big mapping class groups "detect" surfaces or (if time allows) that the space of non-trivial quasimorphisms of a big mapping class group is infinite dimensional.