Nef cone and Seshadri constants on products of projective bundles over curves

Rupam Karmakar; Snehajit Misra

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arXiv · 1812.03957

Nef cone and Seshadri constants on products of projective bundles over curves

Rupam Karmakar·Snehajit Misra

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Abstract

Let $X = \mathbb{P}(E_1) \times_C \mathbb{P}(E_2)$ where $C$ is a smooth curve and let $E_1$, $E_2$ be vector bundles over $C$. In this paper, we extend the results in \cite{K-M-R} by computing the nef cone of $X$ without restriction on the rank or semistability of $E_1$ and $E_2$. We also study the Seshadri constants of ample line bundles on $X$. We calculate the Seshadri constants in some cases and give bounds in some of the remaining cases.

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BibTeX RIS

Rupam Karmakar, Snehajit Misra. 2018-12-10. Nef cone and Seshadri constants on products of projective bundles over curves. https://arxiv.org/abs/1812.03957

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