Local asymptotics near a smooth boundary point and estimates for a hyperbolic-type metric

In this paper, we investigate the local boundary behaviour of a recently developed hyperbolic-type metric $m_D$.

First, employing a boundary-flattening technique and local behaviour of $m_D$-geodesics, we establish its asymptotic formula near any $C^1$-smooth boundary point.

Next, we introduce a metric quantity analogous to the Nikolov--Andreev metric and show that $m_D$ is the inner metric associated with it.

Finally, by establishing a sharp two-sided comparison inequality, we obtain an improved lower bound for the $m_D$-metric.