Uniqueness of K-polystable degenerations of Fano varieties

被引:47
作者
Blum, Harold [1 ]
Xu, Chenyang [2 ,3 ]
机构
[1] Univ Utah, Salt Lake City, UT 84112 USA
[2] Beijing Int Ctr Math Res, Beijing, Peoples R China
[3] MIT, 77 Massachusetts Ave, Cambridge, MA 02139 USA
基金
中国国家自然科学基金; 美国国家科学基金会;
关键词
Fano varieties; K-stability; degenerations; moduli; KAHLER-EINSTEIN METRICS; MODULI SPACES; SCALAR CURVATURE; STABILITY; EXISTENCE; VOLUME; VALUATIONS;
D O I
10.4007/annals.2019.190.2.4
中图分类号
O1 [数学];
学科分类号
0701 ; 070101 ;
摘要
We prove that K-polystable degenerations of Q-Fano varieties are unique. Furthermore, we show that the moduli stack of K-stable Q-Fano varieties is separated. Together with recently proven boundedness and openness statements, the latter result yields a separated Deligne-Mumford stack parametrizing all uniformly K-stable Q-Fano varieties of fixed dimension and volume. The result also implies that the automorphism group of a K-stable Q-Fano variety is finite.
引用
收藏
页码:609 / 656
页数:48
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