波動セミナー Remarks on some isoperimetric properties of the k-1 flow

We consider the evolution of a convex closed plane curve along its inward

normal direction with speed k-1, where k is the curvature. This flow has the

feature that it is the gradient flow of the (length-area) functional and has been

previously studied by Chou-Zhu and Yagisita. Here we revisit the flow again

and point out some interesting isoperimetric properties not discussed before.