Stereographische Projektion und quadratisches Spurenprinzip imR ₄

Abstract

In this article a new method of representing the projective spaceR ₄ in the three-dimensional space Σ is described. This method is based on the stereographical projection of a hypersphere and transfers the straight lines, planes and hyperplanes ofR ₄ into the couples of points, circles and spheres of Σ; the points of theR ₄ are represented by the inversions on the spheres of Σ.