Polynomial harmonic morphisms between Euclidean spheres

Eells, James; Yiu, Paul

doi:10.1090/S0002-9939-1995-1273489-4

Polynomial harmonic morphisms between Euclidean spheres
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by James Eells and Paul Yiu PDF

Proc. Amer. Math. Soc. 123 (1995), 2921-2925 Request permission

Abstract:

A characterization is given of the harmonic morphisms between euclidean spheres whose component functions are harmonic homogeneous polynomials of the same degree, and also of polynomial harmonic morphisms between euclidean spaces which map spheres into spheres. These turn out to be isometric to the classical Hopf fibrations.

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