Tag Archives: graph colouring

Algebraic properties of chromatic roots

It has been a long time coming. I wrote back in 2011 about the work Kerri Morgan and I were doing on algebraic properties of chromatic roots. A paper has just gone on the arXiv. I will just recap here, … Continue reading

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Random orbits on colourings, or nested Markov chains

I promised after reporting Catherine Greenhill’s talk last week that I would advertise this little problem; so here goes. How do we pick a random proper colouring of a graph Γ? There is a simple Markov chain for this, also … Continue reading

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Orbital combinatorics

Yesterday I went to Edinburgh to give a colloquium talk about synchronization, including the recent stuff about butterflies. The day before, I had discussed Artur Schäfer’s work with him, and he expressed a hope that if he went to the … Continue reading

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