5 minutes with Hal Kierstead

Hal Kiersteadhal_profile is a Professor at the School of Mathematical and Statistical Sciences in Arizona State University. He visited our Department in September to work with Jan van den Heuvel and Daniel Quiroz. He also spoke at our Seminar on Combinatorics, Games and Optimisation about the history and applications of generalised colouring numbers, a notion which arose from an idea of Chen and Schelp for using well-chosen vertex orderings to find good bounds on colourings of graphs. This is work which Hal has been working on with fellow authors Alexandr V. (Sasha) Kostochka, William T. (Tom) Trotter, Xuding Zhu and many others. Whilst he was with us, Jan took the opportunity to discover more about Hal’s reserach, career route and interests.