English

One positive and two negative results for derived categories of algebraic stacks

Algebraic Geometry 2015-12-04 v2

Abstract

Let XX be a quasi-compact and quasi-separated scheme. There are two fundamental and pervasive facts about the unbounded derived category of XX: (1) Dqc(X)\mathsf{D}_{\mathrm{qc}}(X) is compactly generated by perfect complexes and (2) if XX is noetherian or has affine diagonal, then the functor ΨX ⁣:D(QCoh(X))Dqc(X)\Psi_X \colon \mathsf{D}(\mathsf{QCoh}(X)) \to \mathsf{D}_{\mathrm{qc}}(X) is an equivalence. Our main results are that for algebraic stacks in positive characteristic, the assertions (1) and (2) are typically false.

Keywords

Cite

@article{arxiv.1405.1888,
  title  = {One positive and two negative results for derived categories of algebraic stacks},
  author = {Jack Hall and Amnon Neeman and David Rydh},
  journal= {arXiv preprint arXiv:1405.1888},
  year   = {2015}
}

Comments

main results strengthened in the noetherian situation; rewrite of Introduction; additional details on well-generation