Abstract
We study $D_4$-singularities of constant mean curvature (CMC) surfaces in Riemannian and semi-Riemannian spaceforms. We will give criteria for $D_4^{-}$-singularities, which are related to the Hopf differential. We also show the non-existence of (spacelike) CMC surfaces with $D_4^+$-singularities.
Information
Digital Object Identifier: 10.2969/aspm/07810345