Orbits of Quaternionic M\"obius Transformations

Abstract

M\"obius transformations of the extended complex plane are at the crossroads of many interesting topics, e.g., they form a group under composition, are the simplest form of rational function, and are a path to Lie theory. Quaternionic transformations are a subgroup of M\"obius transformations isomorphic to rotations of the Riemann sphere, which also represent quaternion conjugation. These representations yield formulas for the axis and radians of rotation, and thereby portray each particular quaternionic transformation as part of a continuous orbit of rotations sharing a common axis.