The University of Michigan Combinatorics Seminar


Abstract 

We will present a simple set of axioms for combinatorial objects
that provide models for "Weyl characters"the characters of
representations of semisimple Lie groups/algebras, or more
generally for "KacWeyl" charactersthe analogues for KacMoody
algebras. Given any set of objects fitting the axioms, it is
trivial to derive rules for computing weight multiplicity, tensor
product multiplicity, and branching (restriction) rules. 