Communications in Number Theory and Physics
Volume 3 (2009)
Differential operators for elliptic genera
Pages: 593 – 618
Using the generalization of Zhu’s recursion relations to $N=2$ superconformal fieldtheories, we construct modular covariant differential operators for weakJacobi forms. We show that differential operators of this type characterizethe elliptic genera of $N=2$ superconformal minimal models, andsketch how they can be used to constrain extremal$N=2$ superconformal field theories.