On the topics of my conversations with Igor Frenkel

Abstract

This is a summary of my lecture at Igor Frenkel's 70th birthday conference. I give a brief review of my almost forty years of scientific interactions with Igor. I focus here on three topics of joint interests: 2-cocycles, coadjoint orbits and $WZ{W}_4$. At the end of each topic I comment on new developments, if any.

arXiv commentBased on the talk delivered at Igor Frenkel's 70th birthday conference. To be published in the AMS Contemporary Mathematics volume, dedicated to Igor Frenkel