Rank-2 wobbly bundles from special divisors on spectral curves

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteur principal: Dinh, Duong
Format: Preprint
Publié: 2024
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866914168937906176
author Dinh, Duong
author_facet Dinh, Duong
contents We study rank-2 wobbly bundles on a Riemann surface $C$ of genus $g\geq 2$, i.e. semi-stable bundles admitting nonzero nilpotent Higgs fields, in terms of direct images of line bundles on smooth spectral curves $\tilde{C} \oversetπ{\rightarrow} C$. We give a sufficient condition for a semi-stable bundle $E$ to be wobbly: $E$ is a twist of $π_\ast \left(\mathcal{O}_{\tilde{C}}(\tilde{D}) \right)$ where the norm of $\tilde{D}$ is a summand of the divisor of a quadratic differential on $C$. We sketch the proof of the necessary condition statement, namely all rank-2 wobbly bundles can be characterised as such, and discuss how certain singularities of the wobbly locus arise from the Brill-Noether loci of spectral curves.
format Preprint
id arxiv_https___arxiv_org_abs_2406_04224
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Rank-2 wobbly bundles from special divisors on spectral curves
Dinh, Duong
Algebraic Geometry
High Energy Physics - Theory
Differential Geometry
We study rank-2 wobbly bundles on a Riemann surface $C$ of genus $g\geq 2$, i.e. semi-stable bundles admitting nonzero nilpotent Higgs fields, in terms of direct images of line bundles on smooth spectral curves $\tilde{C} \oversetπ{\rightarrow} C$. We give a sufficient condition for a semi-stable bundle $E$ to be wobbly: $E$ is a twist of $π_\ast \left(\mathcal{O}_{\tilde{C}}(\tilde{D}) \right)$ where the norm of $\tilde{D}$ is a summand of the divisor of a quadratic differential on $C$. We sketch the proof of the necessary condition statement, namely all rank-2 wobbly bundles can be characterised as such, and discuss how certain singularities of the wobbly locus arise from the Brill-Noether loci of spectral curves.
title Rank-2 wobbly bundles from special divisors on spectral curves
topic Algebraic Geometry
High Energy Physics - Theory
Differential Geometry
url https://arxiv.org/abs/2406.04224