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arXiv · 1808.09713

Regularity of structure sheaves of varieties with isolated singularities

Joaquín Moraga·Jinhyung Park·Lei Song
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Abstract

Let $X\subseteq \mathbb{P}^N$ be a non-degenerate normal projective variety of codimension $e$ and degree $d$ with isolated $\mathbb{Q}$-Gorenstein singularities. We prove that the Castelnuovo-Mumford regularity $\text{reg}(\mathcal{O}_{X})\le d-e$, as predicted by the Eisenbud-Goto regularity conjecture. Such a bound fails for general projective varieties. The main techniques are Noma's classification of non-degenerated projective varieties and Nadel vanishing for multiplier ideals. We also classify the extremal and the next to extremal cases.

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Joaquín Moraga, Jinhyung Park, Lei Song. 2019-09-10. Regularity of structure sheaves of varieties with isolated singularities. https://arxiv.org/abs/1808.09713

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