Andrews-Gordon identities from combinations of Virasoro characters

TL;DR

This paper derives new q-series identities related to Virasoro characters, generalizing Andrews-Gordon identities, through fermionic expressions and character combinations for specific parameters.

Contribution

It introduces novel fermionic expressions for Virasoro characters and derives new identities that extend Andrews-Gordon identities, including W_3 analogues.

Findings

New q-series identities akin to Andrews-Gordon identities.

Fermionic expressions for Virasoro characters for p=3,4, and related cases.

Connections to W_3 characters and identities.

Abstract

For p \in {3, 4} and all p' > p, with p' coprime to p, we obtain fermionic expressions for the combination \chi^{p, p'}_{1, s} + q^{\Delta} \chi^{p, p'}_{p-1,s} of Virasoro (W_2) characters for various values of s, and particular choices of Delta. Equating these expressions with known product expressions, we obtain q-series identities which are akin to the Andrews-Gordon identities. For p=3, these identities were conjectured by Bytsko. For p=4, we obtain identities whose form is a variation on that of the p=3 cases. These identities appear to be new. The case (p,p')=(3,14) is particularly interesting because it relates not only to W_2, but also to W_3 characters, and offers W_3 analogues of the original Andrews-Gordon identities. Our fermionic expressions for these characters differ from those of Andrews et al which involve Gaussian polynomials.