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                * Princeton Discrete Math Seminar *
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Date: Thursday 20th September, 2.00 in Fine Hall 224 
(note the change of time; this is permanent!)

Speaker: Peter Nelson (Wellington)

Title: The Erdos-Stone Theorem for finite geometries

Abstract: For any class of graphs, the growth function h(n) of the class is
defined to be the maximum number of edges in a graph in the class on n
vertices. The Erdos-Stone Theorem remarkably states that, for any class of
graphs that is closed under taking subgraphs, the asymptotic behaviour of
h(n) can (almost) be precisely determined just by the minimum chromatic
number of a graph not in the class. I will present a surprising version of
this theorem for finite geometries, obtained in joint work with Jim Geelen.
This result is a corollary of the famous Density Hales-Jewett Theorem of
Furstenberg and Katznelson. 

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Next week: Wesley Pegden

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