Absolute prismatic cohomology
Bhargav Bhatt, Jacob Lurie
TL;DR
The paper develops a geometric framework for absolute prismatic cohomology by associating prismatic crystals on Spf(Z_p) with quasi-coherent sheaves on the Cartier-Witt stack $ ext{WCart}$. It introduces the Nygaard filtration, the diffracted Hodge complex, and the Hodge-Tate divisor to link prismatic data with de Rham and crystalline theories, and defines syntomic cohomology with canonical Chern classes to connect to étale and K-theoretic invariants. Central innovations include the Breuil-Kisin twist, the prismatic logarithm, and a robust stacky calculus on $ ext{WCart}$ and its HT locus, enabling explicit comparisons and descent results across absolute and relative prismatic cohomology. The framework yields practical computational tools (e.g., using the q-de Rham prism) and clarifies how Frobenius and the Sen operator govern the interaction between HT and non-HT components, with far-reaching implications for $p$-adic Hodge theory and related cohomological theories.
Abstract
The goal of this paper is to study the absolute prismatic cohomology of $p$-adic formal schemes. We do so by recasting the notion of a prismatic crystal on $\mathrm{Spf}(\mathbf{Z}_p)$ in terms of quasicoherent sheaves on a geometric object we call the Cartier-Witt stack.
