Abstract

AbstractFor a connected reductive groupGover a finite field, we study automorphic vector bundles on the stack ofG-zips. In particular, we give a formula in the general case for the space of global sections of an automorphic vector bundle in terms of the Brylinski-Kostant filtration. Moreover, we give an equivalence of categories between the category of automorphic vector bundles on the stack ofG-zips and a category of admissible modules with actions of a 0-dimensional algebraic subgroup a Levi subgroup and monodromy operators.

Highlights

  • The stack of -zips was introduced by Pink-Wedhorn-Ziegler [PWZ11] and [PWZ15] based on the notion of F-zip defined in the work of Moonen-Wedhorn ([MW04])

  • The second author and Wedhorn have used the stack -Zip to construct -ordinary Hasse invariants in [KW18], and this result was later generalised to all Ekedahl-Oort strata with Goldring [GK19a]

  • In [Kos19], the second author studied the space of global sections of the family of vector bundles (V ( )) ∈ ∗ ( )

Read more

Summary

Introduction

The stack of -zips was introduced by Pink-Wedhorn-Ziegler [PWZ11] and [PWZ15] based on the notion of F-zip defined in the work of Moonen-Wedhorn ([MW04]). In [Kos19], the second author studied the space of global sections of the family of vector bundles (V ( )) ∈ ∗ ( ). For any algebraic -representation ( , ) over , there is a naturally attached vector bundle V( ) of rank dim( ) on -Zip modelled on ( , ) (see Subsection 2.4). In the context of Shimura varieties, there are many interesting vector bundles other than the family ( ( )) , which may not always arise from representations in Rep( ). Shimura varieties after choosing a Siegel embedding It extends to a vector bundle on the integral model of Kisin and Vasiu. There is a natural functor Rep( ) → ( ), where ( ) denotes the category of vector bundles on. The results of this article will be used in the follow-up articles [IK21] and [GIK21], where we study partial Hasse invariants for Shimura varieties of Hodge type

Notation
Reminders about representation theory
Vector bundles on the stack of -zips
Automorphic vector bundles on -ZipZ Fix a zip datum
Shimura varieties
The space of -ordinary sections
Brylinski-Kostant filtration
Main result
Perfection
Zip datum
Category of automorphic vector bundles on -Zip
The algebras and Δ
Example on -semisimplification
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call