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arXiv · 2202.05287

ACC for minimal log discrepancies of terminal threefolds

Jingjun Han·Jihao Liu·Yujie Luo
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Abstract

We prove that the ACC conjecture for minimal log discrepancies holds for threefolds in $[1-\delta,+\infty)$, where $\delta>0$ only depends on the coefficient set. We also study Reid's general elephant for pairs, and show Shokurov's conjecture on the existence of $(\epsilon,n)$-complements for threefolds for any $\epsilon\geq 1$. As a key important step, we prove the uniform boundedness of divisors computing minimal log discrepancies for terminal threefolds. We show the ACC for threefold canonical thresholds, and that the set of accumulation points of threefold canonical thresholds is equal to $\{0\}\cup\{\frac{1}{n}\}_{n\in\mathbb Z_{\ge 2}}$ as well.

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Jingjun Han, Jihao Liu, Yujie Luo. 2022-02-10. ACC for minimal log discrepancies of terminal threefolds. https://arxiv.org/abs/2202.05287

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