An analogue of adjoint ideals and PLT singularities in mixed characteristic
An analogue of adjoint ideals and PLT singularities in mixed characteristic
复制标题
混合特征中伴随理想和PLT奇点的类比
DOI:
10.1090/jag/797
复制
发表时间:
2022
影响因子:
1.8
通讯作者:
Witaszek, Jakub
中科院分区:
文献类型:
--
作者:
Ma, Linquan;Schwede, Karl;Tucker, Kevin;Waldron, Joe;Witaszek, Jakub
We use the framework of perfectoid big Cohen-Macaulay algebras to define a class of singularities for pairs in mixed characteristic, which we call purely BCM-regular singularities, and a corresponding adjoint ideal. We prove that these satisfy adjunction and inversion of adjunction with respect to the notion of BCM-regularity and the BCM test ideal defined by the first two authors. We compare them with the existing equal characteristic PLT and purely-regular singularities and adjoint ideals. As an application, we obtain a uniform version of the Brian\c{c}on-Skoda theorem in mixed characteristic. We also use our theory to prove that two-dimensional KLT singularities are BCM-regular if the residue characteristic, which implies an inversion of adjunction for three-dimensional PLT pairs of residue characteristic. In particular, divisorial centers of PLT pairs in dimension three are normal when. Furthermore, in the appendix we provide a streamlined construction of perfectoid big Cohen-Macaulay algebras and show new functoriality properties for them using the perfectoidization functor of Bhatt and Scholze.