Hello everyone.
I am trying to prove that the in a planar domain U \subseteq C equipped with a metric \rho, the definition of the distance between P and Q, both lying in U is given by
\\ \\ d_{\rho}(P,Q)=inf \left\{ L_{\rho}(\gamma): \gamma \in C_{U}(P,Q)\right\},
where C_{U}(P,Q) denotes all...