Department of Mathematics Colloquium

University of Idaho

Fall 2013

Thursday,  September 26, 3:30-4:20 pm, room TLC 145

Refreshments in Brink 305 at 3:00 pm

The odd world of Thompson's groups


Sean Cleary

Department of Mathematics

The City College of New York


In the early 1960's Richard J. Thompson discovered a fascinating family of infinite groups in connection with his work in logic. These groups have reappeared in a wide variety of settings, including homotopy theory, measure theory of discrete groups, non-associative algebras, dynamical systems and geometric group theory.  Thompson's group F is the simplest known example of a variety of unusual group-theoretic phenomena and has been the subject of a great deal of study.  I will describe these groups from several different perspectives and discuss some of their remarkable properties, particularly some unusual aspects of the geometry of their Cayley graphs.