Braid group and $q$-Racah polynomials

Abstract

The irreducible representations of two intermediate Casimir elements associated to the recoupling of three identical irreducible representations of $U_q({\mathfrak{sl}}_2)$ are considered. It is shown that these intermediate Casimirs are related by a conjugation involving braid group representations. Consequently, the entries of the braid group matrices are explicitly given in terms of the $q$-Racah polynomials which appear as $6j$-symbols in the Racah problem for $U_q({\mathfrak{sl}}_2)$. Formulas for these polynomials are derived from the algebraic relations satisfied by the braid group representations.

arXiv comment15 pages; added references and Remark 3.1

References in corpus (6)

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