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Combinatorial Models for Weyl Characters

โœ Scribed by John R. Stembridge

Publisher
Elsevier Science
Year
2002
Tongue
English
Weight
248 KB
Volume
168
Category
Article
ISSN
0001-8708

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โœฆ Synopsis

We present a set of axioms for combinatorial objects closely related to those for Kashiwara's crystals. We show that any model for the axioms, such as Littelmann's path model, has a character-a nonnegative sum of irreducible characters for a semisimple Lie group or algebra, or more generally, a symmetrizable Kac-Moody algebra. Moreover, there are simple explicit restriction rules and rules for decomposing the product of any such character by an irreducible character.

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