A naive generalization of the hyperbolic metric

Abstract: Though the hyperbolic metric enjoys many interesting properties but it is not defined in arbitrary subdomains in $\mathbb{R}^n$, $n\geq 2$. The aim of this article is to introduce a hyperbolic-type metric that gives a new way to resolve the above problem. The new metric coincides with the hyperbolic metric on a ball and surprisingly matches with the quasihyperbolic metric not only in half-spaces but also in any unbounded domains. We calculate the density of the metric in some classical domains with some discussions on the curvature. A few characterizations of uniform domains and John disks in terms of this newly defined metric follow immediately. We also study some geometric properties of the metric including the existence of geodesics and the minimal length of a non-trivial closed curve in a multiply connected domains.