Circum- and Inconic Invariants of 3-Periodics in the Elliptic Billiard
arXiv:2004.02680
Abstract
A Circumconic passes through a triangle's vertices; an Inconic is tangent to the sidelines. We study the variable geometry of certain conics derived from the 1d family of 3-periodics in the Elliptic Billiard. Some display intriguing invariances such as aspect ratio and pairwise ratio of focal lengths.
20 pages, 8 figures, 4 tables, 8 videos NOTE: the original contained two parts, after replacement only the 2nd part. the 1st part was moved to another submission: submit/3126471