Fusion rings for degenerate minimal models

We study fusion rings for degenerate minimal models ($p=q$ case) for N=0 and N=1 (super)conformal algebras. We consider a distinguished family of modules at the level $c=1$ and $c=3/2$ and show that the corresponding fusion rings are isomorphic to the representation rings for ${\mathfrak sl}(2, {\bf C})$ and ${\mathfrak osp}(1|2)$ respectively.Comment: Revised and enlarged version. It includes all the results from math.QA/0101165 (to appear in Journal of Algebra

Formal differential operators, vertex operator algebras and zeta--values , II

We introduce certain correlation functions (graded $q$--traces) associated to vertex operator algebras and superalgebras which we refer to as $n$--point functions. These naturally arise in the studies of representations of Lie algebras of differential operators on the circle \cite{Le1}--\cite{Le2}, \cite{M}. We investigate their properties and consider the corresponding graded $q$--traces in parallel with the passage from genus 0 to genus 1 conformal field theory. By using the vertex operator algebra theory we analyze in detail correlation functions in some particular cases. We obtain elliptic transformation properties for $q$--traces and the corresponding $q$--difference equations. In particular, our construction leads to correlation functions and $q$--difference equations investigated by S. Bloch and A. Okounkov \cite{BO}.Comment: 46 pages, LaTeX (10pt, small font), 1 figure, BibTe

On W-algebra extensions of (2,p) minimal models: p > 3

This is a continuation of arXiv:0908.4053, where, among other things, we classified irreducible representations of the triplet vertex algebra W_{2,3}. In this part we extend the classification to W_{2,p}, for all odd p>3. We also determine the structure of the center of the Zhu algebra A(W_{2,p}) which implies the existence of a family of logarithmic modules having L(0)-nilpotent ranks 2 and 3. A logarithmic version of Macdonald-Morris constant term identity plays a key role in the paper.Comment: 19 page