Combinatorics Seminar: "Newell-Littlewood numbers"

Abstract: The Newell-Littlewood numbers are tensor product multiplicities of Weyl modules for the classical groups in the stable range. Littlewood-Richardson coefficients form a special case. A. Klyachko connected eigenvalues of sums of Hermitian matrices to the saturated LR-cone and established defining linear inequalities. We prove analogues for the saturated NL-cone: an eigenvalue interpretation and a previously conjectured description by Extended Horn inequalities. This is joint work with S. Gao, N. Ressayre, and A. Yong; see
https://arxiv.org/abs/2005.09012
https://arxiv.org/abs/2009.09904
https://arxiv.org/abs/2107.03152.

Host: Martha Precup