UM Math Graduate Student Seminar

James McKeown
University of Miami

will present

The Combinatorics of the Waldspurger Decomposition

Friday, February 19, 2016, 5:00pm
Ungar Building Room 402


In 2005 J.L. Waldspurger proved a remarkable theorem.  Given a finite reflection group G, the closed cone over the positive roots is equal to the disjoint union of images of the open weight cone under the action of 1-g. When G is taken to be the symmetric group the decomposition is related to the familiar combinatorics of permutations but also has some surprising features.  To see this, we give a nice combinatorial description of the decomposition.


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