There’s a short memoir out this evening on the arXiv by Peter Freund about the algebraist Irving Kaplansky, universally known as “Kap”, who died last year at the age of 89. Freund worked with Kaplansky at Chicago during the mid-seventies on the classification of Lie superalgebras, and comments about the relations between math and physics at that time. He also claims that Kaplansky told him with assurance that Hopf algebras couldn’t possibly be of relevance to physics, and that Andre Weil was the greatest living mathematician, since he called all the courses he taught “mathematics”, and lived up to this title. Freund also tells a well-known story about a talk by Weil at Chicago that he heard about first-hand from Kaplansky.
I have my own personal recollections of Kap since he was director of MSRI the year that I was a postdoc there (1988-9), a year during which I unfortunately had only a few short conversations with him. The conversation with him I remember best was our first, which occurred on the phone. In early 1988 I was working part-time teaching Calculus at Tufts and had applied for several full-time mathematics jobs for the next year, not at all sure that there was any chance this would work out, since my Ph.D. and first postdoc had been in physics. When the call came from Kap offering me a job at MSRI for the next year I was elated, partly because Berkeley is one of my favorite places to live as well as being an excellent place to work in both mathematics and physics. During our conversation Kap told me a bit about his work on and continued interest in supersymmetry. I didn’t really have the heart to tell him that because my own inclinations are so geometric, I’d always found supersymmetry and superalgebras a tantalizing but very frustrating subject.