Littelmann's path crystal and combinatorics of certain sl_{l+1}^ modules of level zero
arXiv:math/0206263 · doi:10.1016/S0021-8693(03)00304-1
Abstract
We construct a subcrystal of the Littelmann's path crystal whose formal character coincides with that of a certain simple integrable module of level zero over the untwisted affine Lie algebra associated to sl_n. We also establish an analogue of the Littlewood-Richardson rule for the tensor product of that crystal with a highest weight crystal.
25 pages, AMSLaTeX; to appear in the "Journal of Algebra"