On semi-finite vector bundles with connection over Kahler manifolds

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Amrutiya, Sanjay, Biswas, Indranil
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909750836330496
author Amrutiya, Sanjay
Biswas, Indranil
author_facet Amrutiya, Sanjay
Biswas, Indranil
contents Let $X$ be a compact connected Kähler manifold. We consider the category $\mathcal{C}^\mathrm{EC}(X)$ of flat holomorphic connections $(E,\, \nabla^E)$ over $X$ satisfying the condition that the underlying holomorphic vector bundle $E$ admits a filtration of holomorphic subbundles preserved by the connection $\nabla^E$ such that the monodromy of the induced connection on each successive quotient has finite image. The category $\mathcal{C}^\mathrm{EC}(X)$, equipped with the neutral fiber functor that sends any object $(E,\, \nabla^E)$ to the fiber $E_{x_0}$, where $x_0\, \in\, X$ is a fixed point, defines a neutral Tannakian category over $\mathbb{C}$. Let $\varpi^{\mathrm{EC}}(X,\, x_0)$ denote the affine group scheme corresponding to this neutral Tannakian category $\mathcal{C}^\mathrm{EC}(X)$. Let $π^{\mathrm{EN}}(X,\, x_0)$ be an extension of the Nori fundamental group scheme over $\mathbb{C}$. We show that $π^{\mathrm{EN}}(X,\, x_0)$ is a closed subgroup scheme of $\varpi^{\mathrm{EC}}(X,\, x_0)$. Finally, we discuss an example illustrating that if $X$ is not Kähler, then the natural homomorphism $π^{\mathrm{EN}}(X,\, x_0)\, \longrightarrow\, \varpi^{\mathrm{EC}}(X,\, x_0)$ might fail to be an embedding.
format Preprint
id arxiv_https___arxiv_org_abs_2508_17048
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle On semi-finite vector bundles with connection over Kahler manifolds
Amrutiya, Sanjay
Biswas, Indranil
Algebraic Geometry
53C07, 14C34, 16D90, 14K20
Let $X$ be a compact connected Kähler manifold. We consider the category $\mathcal{C}^\mathrm{EC}(X)$ of flat holomorphic connections $(E,\, \nabla^E)$ over $X$ satisfying the condition that the underlying holomorphic vector bundle $E$ admits a filtration of holomorphic subbundles preserved by the connection $\nabla^E$ such that the monodromy of the induced connection on each successive quotient has finite image. The category $\mathcal{C}^\mathrm{EC}(X)$, equipped with the neutral fiber functor that sends any object $(E,\, \nabla^E)$ to the fiber $E_{x_0}$, where $x_0\, \in\, X$ is a fixed point, defines a neutral Tannakian category over $\mathbb{C}$. Let $\varpi^{\mathrm{EC}}(X,\, x_0)$ denote the affine group scheme corresponding to this neutral Tannakian category $\mathcal{C}^\mathrm{EC}(X)$. Let $π^{\mathrm{EN}}(X,\, x_0)$ be an extension of the Nori fundamental group scheme over $\mathbb{C}$. We show that $π^{\mathrm{EN}}(X,\, x_0)$ is a closed subgroup scheme of $\varpi^{\mathrm{EC}}(X,\, x_0)$. Finally, we discuss an example illustrating that if $X$ is not Kähler, then the natural homomorphism $π^{\mathrm{EN}}(X,\, x_0)\, \longrightarrow\, \varpi^{\mathrm{EC}}(X,\, x_0)$ might fail to be an embedding.
title On semi-finite vector bundles with connection over Kahler manifolds
topic Algebraic Geometry
53C07, 14C34, 16D90, 14K20
url https://arxiv.org/abs/2508.17048