We study, in the path realization, crystals for Demazure modules of affine Lie algebras of types A Ž1. , B Ž1. , C Ž1. , D Ž1. , A Ž2. , A Ž2. , and D Ž2. . We find a special sequence of affine Weyl group elements for the selected perfect crystal, and show that if the highest weight is l⌳ , the Dem
Basic Representations for Classical Affine Lie Algebras
✍ Scribed by Mirko Primc
- Publisher
- Elsevier Science
- Year
- 2000
- Tongue
- English
- Weight
- 342 KB
- Volume
- 228
- Category
- Article
- ISSN
- 0021-8693
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✦ Synopsis
Presented here is a construction of certain bases of basic representations for classical affine Lie algebras. The starting point is a -ޚgrading ᒄ s ᒄ q ᒄ q ᒄ y1 0 1 of a classical Lie algebra ᒄ and the corresponding decomposition ᒄ s ᒄ q ᒄ q ˜˜ỹ 1 0 ᒄ of the affine Lie algebra ᒄ. By using a generalization of the Frenkel᎐Kac vertex ˜1 operator formula for A Ž1. one can construct a spanning set of the basic ᒄ-module 1 in terms of monomials in basis elements of ᒄ and certain group element e. These ˜1 monomials satisfy certain combinatorial Rogers᎐Ramanujan type difference conditions arising from the vertex operator formula, and the main result is that these differences coincide with the energy function of a perfect crystal corresponding to the ᒄ -module ᒄ . The linear independence of the constructed spanning set of the 0 1 basic ᒄ-module is proved by using a crystal base character formula for standard modules due to S.
📜 SIMILAR VOLUMES
In this work a large number of irreducible representations with finite dimensional weight spaces are constructed for some toroidal Lie algebras. To accomplish this we develop a general theory of ޚ n -graded Lie algebras with polynomial multiplication. We construct modules by the standard inducing
Using Littelmann's path model for highest weight representations of Kac᎐Moody algebras, we obtain explicit combinatorial expressions for certain specialized characters of all Demazure modules of A Ž1. and A Ž2. .