English

Prismatic cohomology and de Rham-Witt forms

Algebraic Geometry 2025-08-07 v3 Number Theory

Abstract

For any prism (A,d)(A, d), we construct an analogue of Fontaine's map Wr(A/d)A/dϕ(d)ϕr1(d)W_r(A/d) \to A/d\phi(d)\cdots\phi^{r-1}(d). Subsequently, we define a canonical map from de Rham-Witt forms to prismatic cohomology in the perfect case and prove that it is an isomorphism. Using this result, we obtain an explicit description of the prismatic cohomology for a pp-completed polynomial algebra over A/dA/d.

Keywords

Cite

@article{arxiv.2008.04956,
  title  = {Prismatic cohomology and de Rham-Witt forms},
  author = {Semen Molokov},
  journal= {arXiv preprint arXiv:2008.04956},
  year   = {2025}
}

Comments

20 pages, final version, to appear in Sbornik: Mathematics