English

Complex caustics of the elliptic billiard

Dynamical Systems 2020-02-25 v6 Algebraic Geometry Complex Variables

Abstract

The article studies a generalization of the elliptic billiard to the complex domain. We show that the billiard orbits also have caustics, and that the number of such caustics is bigger than for the real case. For example, for a given ellipse E, there exist exactly two confocal ellipses such that the triangular orbits of E are circumscribed about one of them, and each tangent line to one of those ellipses is a side of a triangular orbit. We also give a bound on the number of caustics for orbits with a fixed number of sides.

Keywords

Cite

@article{arxiv.1904.03706,
  title  = {Complex caustics of the elliptic billiard},
  author = {Corentin Fierobe},
  journal= {arXiv preprint arXiv:1904.03706},
  year   = {2020}
}

Comments

arXiv admin note: substantial text overlap with arXiv:1807.11903

R2 v1 2026-06-23T08:32:08.007Z