Affinizations and braided module categories

Abstract

We relate affinizations of braided monoidal categories to braided module categories, allowing a twist by a braided monoidal automorphism. Our main theorem establishes a bijection between twisted braided structures on a right module category and extensions of its action to the corresponding twisted affinization. We also show that the twisted affinization is the free twisted braided module category on one object. We give explicit presentations of twisted affinizations, both as monoidal categories and as module categories, using invertible dots and reflection relations. We also describe the relation to cylinder twists and tensor-pair cylinder twists, including the naturality condition needed to obtain a braided module structure. As applications, we obtain module-category presentations of the affine Kauffman and affine oriented skein categories and an orientation-reversing twisted version of the latter. We realize the disoriented skein category as a quotient of this twisted affinization by a single additional relation.