Application of Homotopy Theory to Graph Colourings


Prof. Peter Zvengrowski


U. Calgary


Fri, 07/03/2008 - 2:00pm


Sydney University Carslaw 373


In 1955 M. Kneser formulated a conjecture about the number of colours needed to colour certain graphs, which was proved in 1978 by L. Lovasz, using techniques of algebraic topology. In this talk we shall give the simplest version of the proof, which actually proves the more general Dol'nikov Theorem, and is due to J. Greene in 2002. The techniques used are fairly elementary, so all parts of the proof will be explained and should be accessible to students as well as faculty. If time permits some further research of the speaker related to these questions will be discussed.

School Seminar Series: