Hall algebras and Hecke modifications of vector bundles

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Alvarenga, Roberto, Moço, Leonardo
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866918041282936832
author Alvarenga, Roberto
Moço, Leonardo
author_facet Alvarenga, Roberto
Moço, Leonardo
contents In this article, we investigate Hecke modifications of vector bundles on a smooth projective curve $X$ defined over an arbitrary field. We obtain structural results that allow us to reduce the classification problem of Hecke modifications to the case of vector bundles of lower rank. Moreover, when the base field is a finite field and $X$ is the projective line, we apply the Hall algebra of coherent sheaves to provide a full classification of the Hecke modifications, including their multiplicities. These results are applied to study the space of unramified automorphic forms for $\mathrm{PGL}_n$ over the projective line, leading to a proof that the space of unramified toroidal automorphic forms is trivial.
format Preprint
id arxiv_https___arxiv_org_abs_2506_00186
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Hall algebras and Hecke modifications of vector bundles
Alvarenga, Roberto
Moço, Leonardo
Algebraic Geometry
In this article, we investigate Hecke modifications of vector bundles on a smooth projective curve $X$ defined over an arbitrary field. We obtain structural results that allow us to reduce the classification problem of Hecke modifications to the case of vector bundles of lower rank. Moreover, when the base field is a finite field and $X$ is the projective line, we apply the Hall algebra of coherent sheaves to provide a full classification of the Hecke modifications, including their multiplicities. These results are applied to study the space of unramified automorphic forms for $\mathrm{PGL}_n$ over the projective line, leading to a proof that the space of unramified toroidal automorphic forms is trivial.
title Hall algebras and Hecke modifications of vector bundles
topic Algebraic Geometry
url https://arxiv.org/abs/2506.00186