Algebraic Graph Theory - Chris GodsilExport this event to calendar

Thursday, March 28, 2019 — 1:30 PM EDT

Title: Not colouring the 3-sphere

Speaker: Chris Godsil
Affiliation: Unioversity of Waterloo
Room: MC 6486

Abstract:

Let S(3) be the graph formed by the unit vectors in R3, two vectors adjacent if they are orthogonal. I will prove that S(3) has no 3-colouring. The surprise is that the proof involves a detour through the theory of valuations of fields.

Location 
MC - Mathematics & Computer Building
6486
200 University Avenue West

Waterloo, ON N2L 3G1
Canada

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