Friday, May 11, 2012
3:30 pm, MC 5158

Dan Younger
University of Waterloo (adjunct, emeritus)

On Tutte's 3-flow conjecture

An important element of Tutte's research legacy is his trio of k-flow conjectures. These assert that the famous results on k-coulouring planar maps (for k=3,4,5) hold true, in k-flow translation, for graphs that are nonplanar.

Bruce Richter and I have studied the 3-flow conjecture: specifically, its planar version. We have a new proof of Grötzsch's theorem. The method used, reducing the main configuration to the submodularity of cuts, is in the spirit of the conjecture. I will describe this proof.

(this talk is part of a series of talks dedicated to honouring the 10th anniversary of Bill Tutte's passing)