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arXiv · 2007.12425

On the positivity of high-degree Schur classes of an ample vector bundle

Jian Xiao
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Abstract

Let $X$ be a smooth projective variety of dimension $n$, and let $E$ be an ample vector bundle over $X$. We show that any non-zero Schur class of $E$, lying in the cohomology group of bidegree $(n-1, n-1)$, has a representative which is strictly positive in the sense of smooth forms. This conforms the prediction of Griffiths conjecture on the positive polynomials of Chern classes/forms of an ample vector bundle on the form level, and thus strengthens the celebrated positivity results of Fulton-Lazarsfeld for certain degrees.

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Jian Xiao. 2020-07-24. On the positivity of high-degree Schur classes of an ample vector bundle. https://arxiv.org/abs/2007.12425

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