EVENT DETAILS AND ABSTRACT

Title: Eigenvalue Inequalities and Quantum Cohomology of the Grassmannian
Speaker: Professor Chris Woodward
Speaker Info: Harvard University
Brief Description:
Special Note:
Abstract:

Given the eigenvalues of two Hermitian matrices, what are the possible eigenvalues of the sum? In a recent preprint Klyachko notes that the Hilbert-Mumford criterion in geometric invariant theory gives a solution to this problem, which is related to determining which irreducibles appear in the tensor product of two irreducibles of SU(n). I will talk about recent work with Agnihotri (see alg-geom for a preprint) where we consider the corresponding problem for products of unitary matrices, which is related to decomposing fusion (Verlinde) products of representations of SU(n). The answer is given in terms of quantum cohomology of the Grassmannian.