Cycling along Euler road
Dylan Wyrzykowski
TL;DR
The paper introduces $P_lambda$ points to parametrize the Euler line of $d$-dimensional polygons inscribed in a unit hypersphere and proves that these Euler lines arise inductively from sub-polygons via a central homothety, connecting higher-dimensional geometry to planar cases. Special choices of $\lambda$ recover classical centers, with the Euler line containing the centroid, circumcenter, orthocenter, and nine-point center; the construction shows the Euler line of a single point sprouts higher-dimensional Euler lines. By linking to triangle-center theory through Shinagawa coefficients, the authors derive $\lambda = (u+v)/(3u+v)$ for centers with constant coefficients and report a substantial population of Kimberling centers on the Euler line, including 721 centers known as of 2024-12-30. Specializing to the Encyclopedia of Triangle Centers situates well-known centers within the $P_lambda$ family, providing a dimension-spanning perspective on Euler-line phenomena.
Abstract
We introduce the notion of $P_λ$ points, which canonically parametrize points on the Euler line. This allows us to show that the Euler line of any $d$-dimensional inscribed polygon in Euclidean space arises from the Euler lines of its sub-polygons, beginning from the Euler line of a point in the plane. Furthermore, we situate $P_λ$ points in the literature of modern triangle centers.
