On a symmetry of the category of integrable modules

William J. Cook, Christopher Sadowski

Haisheng Li showed that given a module (W,Y_W(\cdot,x)) for a vertex algebra (V,Y(\cdot,x)), one can obtain a new V-module W^Δ = (W,Y_W(Δ(x)\cdot,x)) if Δ(x) satisfies certain natu…