Hidden SL₂(ℤ)-symmetry in BC_l⁽²⁾

2025/02/05 by K. Iohara, Iohara, K., Yoshihisa Saito +1
Mathematics · Physics and Astronomy · #Advanced Algebra and Geometry #Algebraic structures and combinatorial models #FOS: Mathematics #FOS: Physical sciences #Mathematical Physics (math-ph) #Nonlinear Waves and Solitons #Representation Theory (math.RT)

paper · pdf · doi:10.48550/arxiv.2502.03316

openalex publication_date 2025/02/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

A well-known \(Γ_θ\)-action on the characters of integrable highest weight modules over the affine Lie algebra of type \(BC_l⁽²⁾\) at a positive level is extended to an \(SL₂(ℤ)\)-action at a positive even level by supplementing their twisted characters.

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