Nevanlinna Theory of Algebroid Functions on Complete Kähler Manifolds
Xianjing Dong
TL;DR
This work extends classical Nevanlinna value distribution theory from one complex variable to algebroid functions on complete non-compact Kähler manifolds with curvature constraints, introducing a ν-leaf uniformization to realize algebroid functions as meromorphic objects on a higher-dimensional covering. It develops a full Nevanlinna framework on such manifolds, including First and Second Main Theorems, Defect relations, and Picard-type results, by leveraging Green function techniques, Ricci and curvature bounds, and a detailed analysis of branch structures. The paper further advances algebroid theory by establishing First/Second Main Theorems for algebroid functions, estimating branch divisors, and proving propagation of algebraic dependence and five-value unicity theorems, with separate treatments under non-negative Ricci curvature and non-positive sectional curvature. Overall, the results substantially generalize value distribution and unicity theory to geometric settings, enabling applications to complex geometry and value distribution on Kähler manifolds with curvature constraints.
Abstract
In this paper, we generalize the classical Nevanlinna theory of algebroid functions from $\mathbb C$ to a complete Kähler manifold with either non-negative Ricci curvature or non-positive sectional curvature. As its applications, we establish some Picard type theorems and five-value type theorems for algebroid functions under certain conditions.
