Multi-point Seshadri constants on ruled surfaces

Hanumanthu, Krishna; Mukhopadhyay, Alapan

doi:10.1090/proc/13670

Multi-point Seshadri constants on ruled surfaces
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by Krishna Hanumanthu and Alapan Mukhopadhyay

Proc. Amer. Math. Soc. 145 (2017), 5145-5155

DOI: https://doi.org/10.1090/proc/13670

Published electronically: June 22, 2017

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Abstract:

Let $X$ be a surface and let $L$ be an ample line bundle on $X$. We first obtain a lower bound for the Seshadri constant $\varepsilon (X,L,r)$, when $r \ge 2$. We then assume that $X$ is a ruled surface and study Seshadri constants on $X$ in greater detail. We also make precise computations of Seshadri constants on $X$ in some cases.

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