# 8 septembre 2020: 1 événement

### Mardi 8 septembre 13:45-15:00 - Jacek Krajczok - IMPAN, Warsaw

Type I locally compact quantum groups : coamenability and applications

Résumé : We say that a locally compact quantum group is type I if its
universal C* algebra (which is equal to $C^u_0(\hatG)$) is type I.
This class of quantum groups can be though of as an intermediate step
between compact and general locally compact quantum groups ; they are
significantly more general than compact ones, but still have tractable
representation theory. Similarly to the compact case, one can define
"character-like" operators associated with suitable representations. I
will discuss a result which states that coamenability of G is equivalent
to a certain condition on spectra of these operators. If time permits, I
will also discuss how one can use theory of type I locally compact
quantum groups to show that the quantum space underlying the Toeplitz
algebra does not admit a quantum group structure (joint work with Piotr
Sołtan).

En savoir plus : Séminaire d’Analyse Fonctionnelle