Index and stability of harmonic Gauss maps
\textit{E. A. Ruh} [J. Differ. Geom. 4, 509-513 (1970; Zbl 0206.502)] had proved that an immersed surface \(M\subset E^ 3\) has constant mean curvature h if and only if its Gauss map \(\nu\) : \(M\to S^ 2\) is a harmonic map. The author proves the following interesting result: Theorem. Suppose that \(M\subset E^ 3\) is a compact surface of constant mean curvature and genus g. Then Index(\(\nu\))\(\geq (l\arg est\) integer \(< 1+g/2)\).
scientific article; zbMATH DE number 4201191