The University of Michigan Combinatorics Seminar
Let G be a complex simple Lie group or Kac-Moody group and P a parabolic
subgroup. One of the goals Schubert calculus is to understand the product
structure of the cohomology ring H^*(G/P) with respect to its basis of
Schubert classes. If G/P is the Grassmannian, then the structure constants
corresponding to the Schubert basis are the classical Littlewood-Richardson
coefficients which appear in various topics such as enumerative geometry,
algebraic combinatorics and representation theory.