Constructing equivalences between fusion categories of quantum groups and of vertex operator algebras via quantum gauge groups (2502.06229v4)

Abstract: We explain the structure of proof of our results on a problem that Sergio Doplicher posed in the 90s in the setting of conformal nets, and on a related problem posed by Yi-Zhi Huang in the setting of vertex operator algebras. The latter asks to find a direct construction of an equivalence due to Finkelberg between the quantum group modular fusion category at certain roots of unity and the fusion categories of affine vertex operator algebras at positive integer levels. The former asks for the construction of a quantum gauge group and field algebra for the category of localized endomorphisms of a conformal net, extending Doplicher-Roberts theory of the compact gauge group and field algebra in high dimensional AQFT. We mostly focus on the affine VOA aspects. We solve Huang's problem for all the Lie types for which it is known that the centralizer algebra of the truncated tensor powers of the given generating object V listed by Hans Wenzl in 1998 for the quantum group fusion categories is generated by the representation of braid group associated to the R-matrix and for Huang-Lepowsky ribbon braided tensor structure. In the classical type A, this property becomes the classical Schur-Weyl duality and was used by Doplicher and Roberts to construct SU(d) as a special case of their unique compact gauge group and field algebra in algebraic QFT. Presently, known results in the literature allow to construct the full equivalence for the Lie types A, B, C, D, G_2 and partial equivalence for braiding and associativity morphisms in the Lie types E and F. We also solve a question posed by Frenkel and Zhu in 1992 on the quantum group structure on the Zhu algebra for all Lie types. Our main tool is the construction of a quantum gauge group and a Drinfeld twist method. The structures we find in both contexts extend Doplicher-Roberts symmetric functors which played a central role in their duality theory.