@pustam_egr
Pustam Raut wrote:
> <em> Is it </em>

... \(\left(\text{Lenght}[ \, \alpha \, ] - \text{Lenght}[ \, \beta \, ]\right)^2 = 4 \, \pi^2 \, \left(\text{Distance}_{\text{Hausdorff}}[ \, \alpha, \beta \, ]\right)^2\) ...

> <em> true for two "parallel" closed smooth curves [ \(\alpha\), \(\beta\) ] ? </em>

Surely not e.g. for just any pair of "parallel" (or "equi-distant") closed curves on a globe, cmp. [Parallel (latitude)](https://en.wikipedia.org/wiki/Parallel_(latitude)].

#Length #ArcLength #geometry