English

Profinite and Solid Cohomology

Category Theory 2026-01-28 v2 Rings and Algebras

Abstract

Solid abelian groups, as introduced by Dustin Clausen and Peter Scholze, form a subcategory of all condensed abelian groups satisfying some ''completeness'' conditions and having favourable categorical properties. Given a profinite ring RR, there is an associated condensed ring R\underline{R} which is solid. We show that the natural embedding of profinite RR-modules into solid R\underline{R}-modules preserves Ext\mathrm{Ext} and tensor products, as well as the fact that profinite rings are analytic.

Keywords

Cite

@article{arxiv.2410.08933,
  title  = {Profinite and Solid Cohomology},
  author = {Jiacheng Tang},
  journal= {arXiv preprint arXiv:2410.08933},
  year   = {2026}
}

Comments

27 pages, v2: removed the previous Proposition 3.21 which is wrong, other minor changes

R2 v1 2026-06-28T19:18:00.780Z