English

Open loci results for commutative DG-rings

Commutative Algebra 2021-10-25 v2 Algebraic Geometry

Abstract

Given a commutative noetherian non-positive DG-ring with bounded cohomology which has a dualizing DG-module, we study its regular, Gorenstein and Cohen-Macaulay loci. We give a sufficient condition for the regular locus to be open, and show that the Gorenstein locus is always open. However, both of these loci are often empty: we show that no matter how nice H0(A)\mathrm{H}^0(A) is, there are examples where the Gorenstein locus of AA is empty. We then show that the Cohen-Macaulay locus of a commutative noetherian DG-ring with bounded cohomology which has a dualizing DG-module always contains a dense open set. Our results imply that under mild hypothesis, eventually coconnective locally noetherian derived schemes are generically Cohen-Macaulay, but that even in very nice cases, they need not be generically Gorenstein.

Keywords

Cite

@article{arxiv.2002.05055,
  title  = {Open loci results for commutative DG-rings},
  author = {Liran Shaul},
  journal= {arXiv preprint arXiv:2002.05055},
  year   = {2021}
}

Comments

10 pages, final version, to appear in Journal of Pure and Applied Algebra

R2 v1 2026-06-23T13:39:44.508Z