Bosonic Formulas for Affine Branching Functions

E. B. Feigin

Funkcionalʹnyj analiz i ego priloženiâ, Tome 42 (2008) no. 1, pp. 63-77.

Résumé

In this paper, we derive two bosonic (alternating sign) formulas for branching functions of affine Kac–Moody Lie algebras $\mathfrak{g}$. Both formulas are expressed in terms of the Weyl group and string functions of $\mathfrak{g}$.

Détail

Keywords: Kac–Moody algebra, branching function, BGG-resolution.

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