English

Balmer spectra and Drinfeld centers

Category Theory 2024-05-01 v4 Quantum Algebra Rings and Algebras Representation Theory

Abstract

The Balmer spectrum of a monoidal triangulated category is an important geometric construction which is closely related to the problem of classifying thick tensor ideals. We prove that the forgetful functor from the Drinfeld center of a finite tensor category C{\mathbf{C}} to C{\mathbf{C}} extends to a monoidal triangulated functor between their corresponding stable categories, and induces a continuous map between their Balmer spectra. We give conditions under which it is injective, surjective, or a homeomorphism. We apply this general theory to prove that Balmer spectra associated to finite-dimensional cosemisimple quasitriangular Hopf algebras (in particular, group algebras in characteristic dividing the order of the group) coincide with the Balmer spectra associated to their Drinfeld doubles, and that the thick ideals of both categories are in bijection. An analogous theorem is proven for certain Benson--Witherspoon smash coproduct Hopf algebras, which are not quasitriangular in general.

Keywords

Cite

@article{arxiv.2010.11287,
  title  = {Balmer spectra and Drinfeld centers},
  author = {Kent B. Vashaw},
  journal= {arXiv preprint arXiv:2010.11287},
  year   = {2024}
}

Comments

Results in Section 2 strengthened, other edits made in response to suggestions by the referee. Accepted for publication in Algebra Number Theory. 31 pages

R2 v1 2026-06-23T19:32:06.916Z