Hecke modifications of conformal blocks outside the critical level

Raschid Abedin, Giovanni Felder, Robert Windesheim

Published: 2025/9/2

Abstract

We define Hecke modifications of conformal blocks over affine Lie algebras at non-critical level by using the Hecke modifications of the underlying $G$-bundles. We show that this procedure is equivalent to the insertion of a twisted vacuum module at an additional marked point and provide an explicit description using coordinate transformations.