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The energy of unit vector fields on the 3-sphere

A. Higuchi·B. S. Kay·C. M. Wood
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Abstract

The stability of the 3-dimensional Hopf vector field, as a harmonic section of the unit tangent bundle, is viewed from a number of different angles. The spectrum of the vertical Jacobi operator is computed, and compared with that of the Jacobi operator of the identity map on the 3-sphere. The variational behaviour of the 3-dimensional Hopf vector field is compared and contrasted with that of the closely-related Hopf map. Finally, it is shown that the Hopf vector fields are the unique global minima of the energy functional restricted to unit vector fields on the 3-sphere.

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A. Higuchi, B. S. Kay, C. M. Wood. 2000-05-31. The energy of unit vector fields on the 3-sphere. https://doi.org/10.1016/s0393-0440(00)00034-6

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