Peak sections and Bergman kernels on Kähler manifolds with complex hyperbolic cusps
Shengxuan Zhou
TL;DR
This work establishes a higher-dimensional localization principle for Bergman kernels on Kähler manifolds with complex hyperbolic cusps by refining Tian's peak section method. It provides precise $C^k$-type comparisons between the global Bergman kernel and cusp-model kernels, including explicit expressions and asymptotics on complex hyperbolic cusps, Poincaré cusps, and ball quotients. The results yield sharp localization near cusps, KE-cusp refinements, and quotient-geometry asymptotics that have potential implications for log-K stability and Shimura-variety geometry. Overall, the paper delivers a rigorous framework for understanding how cusp geometry governs Bergman kernel behavior, with broad applicability to arithmetic and geometric contexts where cusped Kähler manifolds arise.
Abstract
By revisiting Tian's peak section method, we obtain a localization principle of the Bergman kernels on Kähler manifolds with complex hyperbolic cusps, which is a generalization of Auvray-Ma-Marinescu's localization result Bergman kernels on punctured Riemann surfaces [Auvray-Ma-Marinescu, Math. Ann., 2021]. Then we give some further estimates when the metric on the complex hyperbolic cusp is a Kähler-Einstein metric or when the manifold is a quotient of the complex ball. By applying our method directly to Poincaré type cusps, we also get a partial localization result.
