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arXiv · 2501.05065

Seshadri constants and negative curves on blowups of ruled surfaces

Cyril J. Jacob·Bivas Khan·Ronnie Sebastian
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Abstract

In this article we compute Seshadri constants of ample line bundles on the blowup of Hirzebruch surface $\mathbb{F}_e$ at $r\leqslant e+3$ very general points. Similarly, we compute Seshadri constants on the blowups of certain decomposable ruled surfaces over smooth curves of non-zero genus. We also prove some results related to bounded negativity of blowups of Hirzebruch surfaces and ruled surfaces.

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Cyril J. Jacob, Bivas Khan, Ronnie Sebastian. 2025-01-09. Seshadri constants and negative curves on blowups of ruled surfaces. https://arxiv.org/abs/2501.05065

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