Kähler-Einstein metrics with prescribed singularities on Fano manifolds
arXiv:2006.09130 · doi:10.1515/crelle-2022-0047
Abstract
Given a Fano manifold we develop a variational approach to characterize analytically the existence of Kähler-Einstein metrics with prescribed singularities, assuming that these singularities can be approximated algebraically. Moreover, we define a function on the set of prescribed singularities which generalizes Tian's -invariant, showing that its upper level set produces a subset of the Kähler-Einstein locus, i.e. of the locus given by all prescribed singularities that admit Kähler-Einstein metrics. In particular, we prove that many -stable manifolds admit all possible Kähler-Einstein metrics with prescribed singularities. Conversely, we show that enough positivity of the -invariant function at non-trivial prescribed singularities (or other conditions) implies the existence of genuine Kähler-Einstein metrics. Finally, through a continuity method, we also prove the strong continuity of Kähler-Einstein metrics on curves of totally ordered prescribed singularities when the relative automorphism groups are discrete.
Definition of the -function and Theorem A modified, other related changes. Improved and final version: to appear in "Journal für die reine und angewandte Mathematik (Crelle's Journal)"