The Kustaanheimo-Stiefel map, the Hopf fibration and the square root map on \(\mathbb R^{3}\) and \(\mathbb R^{4}\)
An explicitly defined mapping called the Kustaanheimo-Stiefel map is described. This mapping is related with the Hopf fibration \(S^3 \to S^2\), generalizing the complex squaring map \(z \to z^2\) and not quaternion multiplication.
scientific article; zbMATH DE number 5156452