Coexistence of periodic-2 and periodic-3 caustics for nearly circular analytic billiard maps
arXiv:1711.10541 · doi:10.3934/dcds.2019278
Abstract
For symmetrically analytic deformation of the circle (with certain Fourier decaying rate), the necessary condition for the corresponding billiard map to keep the coexistence of periodic caustics is that the deformation has to be an isometric transformation.