Holomorphic 1-forms on the moduli space of curves

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Favale, F. F., Pirola, G. P., Torelli, S.
Natura: Preprint
Pubblicazione: 2020
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866913595504197632
author Favale, F. F.
Pirola, G. P.
Torelli, S.
author_facet Favale, F. F.
Pirola, G. P.
Torelli, S.
contents Since the sixties it is well known that there are no non-trivial closed holomorphic $1$-forms on the moduli space $\mathcal{M}_g$ of smooth projective curves of genus $g>2$. In this paper, we strengthen such result proving that for $g\geq 5$ there are no non-trivial holomorphic $1$-forms. With this aim, we prove an extension result for sections of locally free sheaves $\mathcal{F}$ on a projective variety $X$. More precisely, we give a characterization for the surjectivity of the restriction map $ρ_D:H^0(\mathcal{F})\to H^0(\mathcal{F}|_{D})$ for divisors $D$ in the linear system of a sufficiently large multiple of a big and semiample line bundle $\mathcal{L}$. Then, we apply this to the line bundle $\mathcal{L}$ given by the Hodge class on the Deligne Mumford compactification of $\mathcal{M}_g$.
format Preprint
id arxiv_https___arxiv_org_abs_2009_10490
institution arXiv
publishDate 2020
record_format arxiv
spellingShingle Holomorphic 1-forms on the moduli space of curves
Favale, F. F.
Pirola, G. P.
Torelli, S.
Algebraic Geometry
Complex Variables
14H15, 32L10
Since the sixties it is well known that there are no non-trivial closed holomorphic $1$-forms on the moduli space $\mathcal{M}_g$ of smooth projective curves of genus $g>2$. In this paper, we strengthen such result proving that for $g\geq 5$ there are no non-trivial holomorphic $1$-forms. With this aim, we prove an extension result for sections of locally free sheaves $\mathcal{F}$ on a projective variety $X$. More precisely, we give a characterization for the surjectivity of the restriction map $ρ_D:H^0(\mathcal{F})\to H^0(\mathcal{F}|_{D})$ for divisors $D$ in the linear system of a sufficiently large multiple of a big and semiample line bundle $\mathcal{L}$. Then, we apply this to the line bundle $\mathcal{L}$ given by the Hodge class on the Deligne Mumford compactification of $\mathcal{M}_g$.
title Holomorphic 1-forms on the moduli space of curves
topic Algebraic Geometry
Complex Variables
14H15, 32L10
url https://arxiv.org/abs/2009.10490