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arXiv · 0709.3937

Discrete behavior of Seshadri constants on surfaces

Brian Harbourne·Joaquim Roe
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Abstract

Working over C, we show that, apart possibly from a unique limit point, the possible values of multi-point Seshadri constant for general points on smooth projective surfaces form a discrete set. In addition to its theoretical interest, this result is of practical value, which we demonstrate by giving significantly improved explicit lower bounds for Seshadri constants on P^2 and new results about ample divisors on blow ups of P^2 at general points.

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Brian Harbourne, Joaquim Roe. 2007-09-25. Discrete behavior of Seshadri constants on surfaces. https://doi.org/10.1016/j.jpaa.2007.06.018

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