Twistor fibrations over Hermitian symmetric spaces and harmonic maps (Q1001990)

The main theorem of the paper under review provides the construction of a certain holomorphic map from a twistor space of a given Hermitian symmetric space of compact type onto a twistor space of an inner symmetric space of compact type. The map referred to in the statement also preserves the superhorizontal distributions. The construction relies on the notion of a canonical element in a simple Lie algebra, as introduced by [\textit{F. E. Burstall} and \textit{J. H. Rawnsley}, Twistor theory for Riemannian symmetric spaces. With applications to harmonic maps of Riemann surfaces. Lecture Notes in Mathematics, 1424. (Berlin) etc.: Springer-Verlag. (1990; Zbl 0699.53059)]. Then the theorem is applied in order to construct isotropic harmonic maps from Riemann surfaces into inner symmetric spaces.