88直播

Geometric Representation Theory Seminar

Organizers：

Lin Chen, Will Donovan, Penghui Li, Peng Shan, Changjian Su, Wenbin Yan

Speaker：

Cédric Bonnafé

(IMAG, Université de Montpellier)

Time：

Mon., 3:30-4:30 pm, Mar. 23, 2026

Venue：

B627, Shuangqing Complex Building

Title:

Exceptional varieties built from exceptional reflection groups

Abstract:

There are many ways for a variety to be "exceptional", but we focus in this talk on some old problems in classical algebraic geometry: finding curves and surfaces with many singular points, with big automorphism groups, finding surfaces with many lines or conics, finding K3 surfaces with big Picard numbers... We present a series of examples, all built from invariants of exceptional complex reflection groups, which are up to now the records in their own categories.