A Hodge-Tate decomposition with rigid analytic coefficients
Lucas Gerth
TL;DR
The authors extend the Hodge--Tate framework to proper smooth rigid spaces $X$ with coefficients in locally $p$-divisible groups $G$, establishing a $G$-coefficient HT decomposition and proving a geometric HT spectral sequence degenerates at $E_2$. They develop diamantine higher direct images to organize moduli of $G$-torsors, proving a degeneracy for the geometric spectral sequence and deriving both the standard HT decomposition and a relative version over a base $S$. The results connect to analytic Brauer groups and provide a geometric $p$-adic Simpson correspondence, including explicit treatments for abeloid varieties and curves via fundamental-group descriptions. The work blends good/adic space theory, smoothoid geometry, and tilde-limit approximation to relate étale and $v$-topologies, yielding tools with broad impact on non-abelian $p$-adic Hodge theory and relative cohomology.
Abstract
Let $X$ be a smooth proper rigid analytic space over a complete algebraically closed field extension $K$ of $\mathbb{Q}_p$. We establish a Hodge--Tate decomposition for $X$ with $G$-coefficients, where $G$ is any commutative locally $p$-divisible rigid group. This generalizes the Hodge--Tate decomposition of Faltings and Scholze, which is the case $G=\mathbb{G}_a$. For this, we introduce geometric analogs of the Hodge--Tate spectral sequence with general locally $p$-divisible coefficients. We prove that these spectral sequences degenerate at $E_2$. Our results apply more generally to a class of smooth families of commutative adic groups over $X$ and in the relative setting of smooth proper morphisms $X\rightarrow S$ of smooth rigid spaces. We deduce applications to analytic Brauer groups and the geometric $p$-adic Simpson correspondence.
