Joel Friedman

The so called "Moore Bound" is one of the great puzzles of graph theory. It is an upper bound on the girth of a d-regular graph on n vertices; it is almost immediate, and appeared in publication roughly 50 years ago. However, this bound has only been...

In these talks we describe our proofs of the Hanna Neumann Conjecture. This conjecture of the late 1950's can be described both as a problem in group theory or as one in graph theory. Our first proof is longer and interprets the problem using...

In these talks we describe our proofs of the Hanna Neumann Conjecture. This conjecture of the late 1950's can be described both as a problem in group theory or as one in graph theory. Our first proof is longer and interprets the problem using...

This is the 12th in a series of biennial meetings that have been held at various sites throughout Western Canada, beginning with an inaugural meeting at the University of Regina in 1993. WCLAM provides an opportunity for researchers and...