Polytope sums and Lie characters Mark Walton (walton@uleth.ca) Abstract Results on exponential
sums of convex lattice polytopes are applied to the characters of irreducible
representations of simple Lie algebras. The Brion formula is used to write
a useful character formula that manifests weight-multiplicity-degeneracy
beyond that explained by Weyl symmetry. It also allows the derivation
of a character generator relevant to affine fusion, the fusion of Wess-Zumino-Witten
conformal field theories. |