CRYSTALLIZING FUNCTIONS ON COMPACT LIE GROUPS
- Speaker(s)
- ROBERT YUNCKEN
- Affiliation
- Université Clermont Auvergne, France
- Date
- June 7, 2023, 5:15 p.m.
- Information about the event
- 405 IMPAN & ZOOM
- Seminar
- North Atlantic Noncommutative Geometry Seminar
The theory of crystal bases, due to Kashiwara and Lusztig, is a means of simplifying the representation theory of semisimple Lie algebras by passing through quantum groups. Specifically, varying the parameter q of a quantized enveloping algebra, we pass from the classical theory at q=1 through the Drinfeld-Jimbo algebras at 0 < q < 1 to the crystal limit at q=0. At this point, the main features of the representation theory (matrix coefficients, Clebsch-Gordan coefficients, branching rules) crystallize into purely combinatorial data described by crystal graphs. In this talk, we will describe what happens to the *-algebra of functions on a compact semisimple Lie group under the crystallization process, leading to a higher-rank graph algebra. This generalizes, in part, work by Woronowicz, Hong and Szymański, and Giselsson. (Joint work with Marco Matassa.)