English

Separable extensions in tensor-triangular geometry and generalized Quillen stratification

Category Theory 2024-09-10 v4 Algebraic Geometry Algebraic Topology Representation Theory

Abstract

We study the continuous map induced on spectra by a separable extension of tensor-triangulated categories. We determine the image of this map and relate the cardinality of its fibers to the degree of the extension. We then prove a weak form of descent, "up-to-nilpotence", which allows us to generalize Quillen's Stratification Theorem to equivariant derived categories.

Keywords

Cite

@article{arxiv.1309.1808,
  title  = {Separable extensions in tensor-triangular geometry and generalized Quillen stratification},
  author = {Paul Balmer},
  journal= {arXiv preprint arXiv:1309.1808},
  year   = {2024}
}

Comments

Final revised version, 17 pages, to appear in Ann. Sci. Ecole Norm. Sup. (4). Formula in Thm.3.4(c) corrected

R2 v1 2026-06-22T01:22:33.364Z