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arXiv · 1604.05398

Stability of Valuations and Koll\'ar Components

Chi Li·Chenyang Xu
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Abstract

We prove that among all Koll\'ar components obtained by plt blow ups of a klt singularity $o \in (X, D)$, there is at most one that is (log-)K-semistable. We achieve this by showing that if such a Koll\'ar component exists, it uniquely minimizes the normalized volume function introduced in [Li15a] among all divisorial valuations. Conversely, we show any divisorial minimizer of the normalized volume function yields a K-semistable Koll\'ar component. We also prove that for any klt singularity, the infimum of the normalized function is always approximated by the normalized volumes of Koll\'ar components.

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Chi Li, Chenyang Xu. 2016-04-19. Stability of Valuations and Koll\'ar Components. https://arxiv.org/abs/1604.05398

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