Lower semi-continuity of the Waldschmidt constants

Daseul Bae

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arXiv · 1802.09755

Lower semi-continuity of the Waldschmidt constants

Daseul Bae

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Abstract

In this paper, we study the Waldschmidt constant of a generalized fat point subscheme $Z=m_1p_1+\cdots+m_rp_r$ of $\mathbb{P}^2$, where $p_1,\cdots,p_r$ are essentially distinct points on $\mathbb{P}^2$, satisfying the proximity inequalities. Furthermore, we prove its lower semi-continuity for $r\le 8$. Using this property, we also calculate the Waldschmidt constants of the fat point subschemes $Z=p_1+\cdots+p_5$ giving weak del Pezzo surfaces of degree 4.

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Daseul Bae. 2018-02-27. Lower semi-continuity of the Waldschmidt constants. https://arxiv.org/abs/1802.09755

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