Department of Mathematics,
University of California San Diego
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Math 264 - Combinatorics
Allen Knutson
University of California at Berkeley
Gluing Young tableaux into a ball
Abstract:
Young tableaux, beloved of combinatorialists, tolerated by representation theorists and geometers, seem at first glance to be an unruly combinatorial set. I'll define a simplicial complex in which they index the facets, and slightly more general objects (Buch's ``set-valued tableaux'') label the other interior faces. The theorem that says we're on a right track: This simplicial complex is homeomorphic to a ball. I'll explain why this is surprising, useful, and shows why Buch didn't discover the exterior faces too. Finally, I'll explain how algebraic geometry forced these definitions on us (or, ``How I made my peace with Young tableaux''). This work is joint with Ezra Miller and Alex Yong.
Host: Jeff Remmel
November 30, 2004
3:00 PM
AP&M 7321
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