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arXiv · 1912.12961

On positivity of the CM line bundle on K-moduli spaces

Chenyang Xu·Ziquan Zhuang
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Abstract

In this paper, we consider the CM line bundle on the K-moduli space, i.e., the moduli space parametrizing K-polystable Fano varieties. We prove it is ample on any proper subspace parametrizing reduced uniformly K-stable Fano varieties which conjecturally should be the entire moduli space. As a corollary, we prove that the moduli space parametrizing smoothable K-polystable Fano varieties is projective. During the course of proof, we develop a new invariant for filtrations which can be used to test various K-stability notions of Fano varieties.

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Chenyang Xu, Ziquan Zhuang. 2020-08-31. On positivity of the CM line bundle on K-moduli spaces. https://doi.org/10.4007/annals.2020.192.3.7

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