English

Stratifications of abelian categories

Representation Theory 2025-06-23 v2 Category Theory

Abstract

This paper studies abelian categories that can be decomposed into smaller abelian categories via iterated recollements - such a decomposition we call a stratification. Examples include the categories of (equivariant) perverse sheaves and epsilon-stratified categories (in particular highest weight categories) in the sense of Brundan-Stroppel (2018). We give necessary and sufficient conditions for an abelian category with a stratification to be equivalent to a category of finite dimensional modules of a finite dimensional algebra - this generalizes the main result of Cipriani-Woolf (2022). Furthermore, we give necessary and sufficient conditions for such a category to be epsilon-stratified - this generalizes the characterisation of highest weight categories given by Krause (2017).

Keywords

Cite

@article{arxiv.2303.14925,
  title  = {Stratifications of abelian categories},
  author = {Giulian Wiggins},
  journal= {arXiv preprint arXiv:2303.14925},
  year   = {2025}
}
R2 v1 2026-06-28T09:34:45.837Z