Giles Gardam
September 17, 2021
(EST (Toronto))
Organized by Americas GNCG Seminar.

Kaplansky’s conjectures

The Kadison–Kaplansky conjecture states that the reduced C*-algebra of a torsion-free discrete group has no idempotents other than 0 and 1. It holds for groups satisfying the Baum–Connes conjecture. If we restrict focus to group algebras, there are stronger conjectures attributed to Kaplansky on zero divisors and units. I will discuss these conjectures and my counterexample to the unit conjecture.

Share on email
Share on facebook
Share on google
Share on twitter
Share on linkedin