An Ogus Principle for Zip period maps: The Hasse invariant's vanishing order via `Frobenius and the Hodge filtration'

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Goldring, Wushi, Reppen, Stefan
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917633831469056
author Goldring, Wushi
Reppen, Stefan
author_facet Goldring, Wushi
Reppen, Stefan
contents This paper generalizes a result of Ogus that, under certain technical conditions, the vanishing order of the Hasse invariant of a family $Y/X$ of $n$-dimensional Calabi-Yau varieties in characteristic $p$ at a point $x$ of $X$ equals the "conjugate line position" of $H^n_{\text{dR}}(Y/X)$ at $x$, i.e. the largest $i$ such that the line of the conjugate filtration is contained in $\text{Fil}^i$ of the Hodge filtration. For every triple $(G,μ,r)$ consisting of a connected, reductive $\mathbf{F}_p$-group $G$, a cocharacter $μ\in X_*(G)$ and an $\mathbf{F}_p$-representation $r$ of $G$, we state a generalized Ogus Principle. If $ζ:X \to \text{$G$-$\mathtt{Zip}$}^μ$ is a smooth morphism (=`Zip period map'), then the group theoretic Ogus Principle implies an Ogus Principle on $X$. We deduce an Ogus Principle for several Hodge and abelian-type Shimura varieties and the moduli space of K3 surfaces.
format Preprint
id arxiv_https___arxiv_org_abs_2404_05707
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle An Ogus Principle for Zip period maps: The Hasse invariant's vanishing order via `Frobenius and the Hodge filtration'
Goldring, Wushi
Reppen, Stefan
Algebraic Geometry
Number Theory
This paper generalizes a result of Ogus that, under certain technical conditions, the vanishing order of the Hasse invariant of a family $Y/X$ of $n$-dimensional Calabi-Yau varieties in characteristic $p$ at a point $x$ of $X$ equals the "conjugate line position" of $H^n_{\text{dR}}(Y/X)$ at $x$, i.e. the largest $i$ such that the line of the conjugate filtration is contained in $\text{Fil}^i$ of the Hodge filtration. For every triple $(G,μ,r)$ consisting of a connected, reductive $\mathbf{F}_p$-group $G$, a cocharacter $μ\in X_*(G)$ and an $\mathbf{F}_p$-representation $r$ of $G$, we state a generalized Ogus Principle. If $ζ:X \to \text{$G$-$\mathtt{Zip}$}^μ$ is a smooth morphism (=`Zip period map'), then the group theoretic Ogus Principle implies an Ogus Principle on $X$. We deduce an Ogus Principle for several Hodge and abelian-type Shimura varieties and the moduli space of K3 surfaces.
title An Ogus Principle for Zip period maps: The Hasse invariant's vanishing order via `Frobenius and the Hodge filtration'
topic Algebraic Geometry
Number Theory
url https://arxiv.org/abs/2404.05707