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arXiv · 1711.07725

Effective cycles on the symmetric product of a curve, II: the Abel-Jacobi faces

Francesco Bastianelli·Alexis Kouvidakis·Angelo Felice Lopez·Filippo Viviani
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Abstract

In this paper, which is a sequel of [BKLV], we study the convex-geometric properties of the cone of pseudoeffective $n$-cycles in the symmetric product $C_d$ of a smooth curve $C$. We introduce and study the Abel-Jacobi faces, related to the contractibility properties of the Abel-Jacobi morphism and to classical Brill-Noether varieties. We investigate when Abel-Jacobi faces are non-trivial, and we prove that for $d$ sufficiently large (with respect to the genus of $C$) they form a maximal chain of perfect faces of the tautological pseudoeffective cone (which coincides with the pseudoeffective cone if $C$ is a very general curve).

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Francesco Bastianelli, Alexis Kouvidakis, Angelo Felice Lopez, Filippo Viviani. 2017-11-21. Effective cycles on the symmetric product of a curve, II: the Abel-Jacobi faces. https://arxiv.org/abs/1711.07725

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