Seshadri constants on hyperelliptic surfaces

Krishna Hanumanthu; Praveen Kumar Roy

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arXiv · 1709.06788

Seshadri constants on hyperelliptic surfaces

Krishna Hanumanthu·Praveen Kumar Roy

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Abstract

We prove new results on single point Seshadri constants for ample line bundles on hyperelliptic surfaces. Given a hyperelliptic surface $X$ and an ample line bundle $L$ on $X$, we show that the least Seshadri constant $\varepsilon(L)$ of $L$ is a rational number when $X$ is not of type 6. We also prove new lower bounds for the Seshadri constant $\varepsilon(L,1)$ of $L$ at a very general point.

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Krishna Hanumanthu, Praveen Kumar Roy. 2017-09-20. Seshadri constants on hyperelliptic surfaces. https://arxiv.org/abs/1709.06788

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