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CATEGORIES:Combinatorics Seminar
SUMMARY:Polychromatic colouring and cover-decomposition pr
oblems in the plane - Dömötör Pálvölgyi (Universit
y of Cambridge)
DTSTART;TZID=Europe/London:20160526T143000
DTEND;TZID=Europe/London:20160526T153000
UID:TALK65480AThttp://talks.cam.ac.uk
URL:http://talks.cam.ac.uk/talk/index/65480
DESCRIPTION:Is it true that given a finite point set on a sphe
re and a set of halfspheres\, such that the set sy
stem that they induce on the point set is a Sperne
r family\, we can select a subset of the points th
at meet every halfsphere in at least one but at mo
st two points?\nI don't know the answer to this qu
estion (waiting to be solved by YOU!)\, but I know
that the above holds in the plane if instead of h
alfspheres we take (pseudo)halfplanes. I will talk
about consequences of similar results in polychro
matic colouring and cover-decomposition\, and also
mention several other open problems.\n
LOCATION:MR12
CONTACT:Andrew Thomason
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