On Some Properties of Squeezing Functions of Bounded Domains

TL;DR

This paper introduces and studies squeezing functions of bounded domains, exploring their properties, boundary behavior, and implications for geometric and analytic structures, including conditions for holomorphic homogeneous regularity.

Contribution

It defines squeezing functions for bounded domains, investigates their properties, and characterizes holomorphic homogeneous regular domains, providing new insights into boundary behavior and explicit examples.

Findings

Holomorphic homogeneous regular domains have squeezing functions with positive lower bounds.

Boundary behavior of squeezing functions characterizes finitely connected planar domains.

Explicit examples of domains with computable squeezing functions are provided.

Abstract

The main purpose of the present paper is to introduce the notion of squeezing functions of bounded domains and study some properties of them. The relation to geometric and analytic structures of bounded domains will be investigated. Existence of related extremal maps and continuity of squeezing functions are proved. Holomorphic homogeneous regular domains are exactly domains whose squeezing functions have positive lower bounds. Completeness of certain intrinsic metrics and pseudoconvexity of holomorphic homogeneous regular domains are proved by alternative method. In dimension one case, we get a neat description of boundary behavior of squeezing functions of finitely connected planar domains. This leads to a necessary and sufficient conditions for a finitely connected planar domain to be a holomorphic homogeneous regular domain. Consequently, we can recover some important results in complex analysis. For annuli, we obtain some interesting properties of their squeezing functions. We finally exhibit some examples of bounded domains whose squeezing functions can be given explicitly.