**Date & Time:** Monday, April 21, 2014, 15:30-16:00.

**Venue:** IRCC Conference Room II, SOM-IRCC Building

**Title:** Orbit method and character sheaves on
unipotent groups in positive characteristic

**Speaker: ** Swarnendu Datta, Yale University

**Abstract:** Recently V. Drinfeld and M. Boyarchenko have developed the theory of character
sheaves on unipotent groups over fields of positive characteristic. The character sheaves are defined
using the notion of minimal idempotents in the equivariant derived category of the unipotent group.
When the nilpotence class of the unipotent group is small, one can describe the minimal
idempotents explicitly using the orbit method. Each minimal idempotent gives rise to a category of
character sheaves, which upon suitable modification, forms a modular category. I shall try to
describe a conjectural explicit description of this category, due to Drinfeld. Part of this conjecture
has been verified in my preprint "Modular categories, orbit method and character sheaves on
unipotent groups".