Modul: MAT070 Zurich Colloquium in Mathematics

## What on earth is going on with subfactors?

Prof. Dr. Vaughan F.R. Jones talk

Speaker invited by: Prof. Dr. Anna Beliakova

**Date:** 20.05.19 **Time:** 16.15 - 17.15 **Room:** Y27H25

**Abstract:** As a first approximation, subfactors can be thought of as groups whose order (the “index” of the subfactor) need not be an integer. Recently all subfactors of index less than 5.25 have been classified. Not very impressive accoding to the group analogy….. Most subfactors on the list are no longer surprises, but there are a few “sporadic” examples which cannot be constructed by known machines such as quantum groups and conformal field theory. I will describe this classification, with pictures, and speculate as to how the subfactor world relates to other parts of mathematics and physics.