English

On pro-cdh descent on derived schemes

K-Theory and Homology 2026-01-21 v3 Algebraic Geometry

Abstract

Grothendieck's formal functions theorem states that the coherent cohomology of a Noetherian scheme can be recovered from that of a blowup and the infinitesimal thickenings of the center and of the exceptional divisor of the blowup. In this article, we prove an analogous descent result, called ``pro-cdh descent'', for certain cohomological invariants of arbitrary quasi-compact, quasi-separated derived schemes. Our results in particular apply to algebraic KK-theory, topological Hochschild and cyclic homology, and the cotangent complex. As an application, we deduce that Kn(X)=0K_n(X) = 0 when n<dn < -d for quasi-compact, quasi-separated derived schemes XX of valuative dimension dd. This generalises Weibel's conjecture, which was originally stated for Noetherian (non-derived) XX of Krull dimension dd, and proved in this form in 2018 by Kerz, Strunk, and the third author.

Keywords

Cite

@article{arxiv.2407.04378,
  title  = {On pro-cdh descent on derived schemes},
  author = {Shane Kelly and Shuji Saito and Georg Tamme},
  journal= {arXiv preprint arXiv:2407.04378},
  year   = {2026}
}

Comments

v1:28 pages, v2:32 pages, now proves vanishing of negative K-groups below the negative valuative dimension for arbitrary qcqs schemes, v3: 32 pages, rewritten abstract and introduction, final version

R2 v1 2026-06-28T17:29:59.652Z