English

Support varieties for transporter category algebras

Group Theory 2011-08-29 v3 Algebraic Topology Rings and Algebras Representation Theory

Abstract

Let G be a finite group. Over any finite G-poset P we may define a transporter category as the corresponding Grothendieck construction. The classifying space of the transporter category is the Borel construction on the G-space BP, while the k-category algebra of the transporter category is the (Gorenstein) skew group algebra on the G-incidence algebra kP. We introduce a support variety theory for the category algebras of transporter categories. It extends Carlson's support variety theory on group cohomology rings to equivariant cohomology rings. In the mean time it provides a class of (usually non selfinjective) algebras to which Snashall-Solberg's (Hochschild) support variety theory applies. Various properties will be developed. Particularly we establish a Quillen stratification for modules.

Keywords

Cite

@article{arxiv.1105.4731,
  title  = {Support varieties for transporter category algebras},
  author = {Fei Xu},
  journal= {arXiv preprint arXiv:1105.4731},
  year   = {2011}
}

Comments

22 pages. Removed some small errors. Added a Lemma 2.3.2 and 2 new references on Gorenstein skew group algebras

R2 v1 2026-06-21T18:11:44.313Z