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Sur la dimension de l'ensemble des points base du fibre determinant sur l'espace des modules des fibres vectoriels semi stables sur une courbe

Olivier Schneider
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Abstract

Resume Soit SU_C(r) l'espace des modules des fibrés vectoriels semi-stables de déterminant trivial sur une courbe lisse $C$ de genre $g \geq 2$ sur $\mathbb{C}$. On étudie dans cet article, un exemple de fibré introduit par Raynaud dans ~\cite{R}, ne possédant pas de diviseur thêta. On construit ensuite des extensions stables de ce fibré ce qui conduit à une majoration de la codimension du lieu de base du fibré déterminant sur $\mathcal{SU}_{C}(r)$. Abstract Let $\mathcal{SU}_{C}(r)$ be the moduli space of semi stable bundles with trivial determinant on a smooth curve $C$ of genus $g\geq 2$ on $\mathbb{C}$. In this article, we are studiying a vector bundle introduced by Raynaud in ~\cite{R}, with no theta divisor. Then we build some stable extension of this bundle wich gives us an upper bound of the codimension of the base locus of the determinant bundle on $\mathcal{SU}_{C}(r)$.

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Olivier Schneider. 2005-01-24. Sur la dimension de l'ensemble des points base du fibre determinant sur l'espace des modules des fibres vectoriels semi stables sur une courbe. https://arxiv.org/abs/math/0501320

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