The importance of being isolated
Commutative Algebra
2026-05-20 v1 Category Theory
Abstract
We give both a sufficient condition for and an obstruction to the derived category of a commutative ring being generated by its residue fields. As an illustration, we exhibit a ring for which Foxby's small support classifies localizing subcategories despite the failure of the local-to-global principle. We also conclude that the residue fields do not generate for a polynomial ring in infinitely many variables. Finally, we give a necessary and sufficient criterion for the derived category to satisfy the local-to-global principle; it turns out to depend solely on the topology of the spectrum.
Keywords
Cite
@article{arxiv.2605.19617,
title = {The importance of being isolated},
author = {Scott Balchin and Juan Omar Gómez and Greg Stevenson},
journal= {arXiv preprint arXiv:2605.19617},
year = {2026}
}
Comments
8 pages, comments welcome