Hermitian-Einstein Metrics on Noncompact Complex Manifolds in Complex Geometry
A Hermitian metric K on a holomorphic vector bundle E is Hermitian-Einstein when the trace of its Chern curvature against the base metric is a constant multiple of the identity endomorphism. On a compact manifold the Kobayashi-Hitchin correspondence says such a metric exists exactly when the bundle is slope-stable. This area asks what survives when the base is the complement M = X \\ Z of a closed (typically analytic or Zariski closed) subset of a compact Hermitian manifold, so the base is noncompact and the usual integration-by-parts and maximum-principle arguments lose their boundary control. The techniques are a perturbed nonlinear heat flow on exhausting subdomains with Dirichlet data, uniform estimates obtained by Moser iteration, a Liouville-type argument for bounded subharmonic functions, and a continuity method in the style of Uhlenbeck-Yau. The payoff is a correspondence on the noncompact base relating an analytic stability condition, formulated with saturated subsheaves and a Gauduchon or Kahler background metric, to the existence and uniqueness of a Hermitian-Einstein metric with prescribed behaviour near the removed set.
Hermitian-Einstein equations on noncompact manifolds
On a holomorphic vector bundle E over a complex manifold, a Hermitian metric H determines a Chern connection whose curvature is F_H; the metric is Hermitian-Einstein when the trace-free part of the c…