Jacobi fields along harmonic 2-spheres in $S^3$ and $S^4$ are not all integrable

Luc Lemaire; John C Wood

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arXiv · 0709.1417

Jacobi fields along harmonic 2-spheres in $S^3$ and $S^4$ are not all integrable

Luc Lemaire·John C Wood

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Abstract

In a previous paper, we showed that any Jacobi field along a harmonic map from the 2-sphere to the complex projective plane is integrable (i.e., is tangent to a smooth variation through harmonic maps). In this paper, in contrast, we show that there are (non-full) harmonic maps from the 2-sphere to the 3-sphere and 4-sphere which have non-integrable Jacobi fields. This is particularly surprising in the case of the 3-sphere where the space of harmonic maps of any degree is a smooth manifold, each map having image in a totally geodesic 2-sphere.

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BibTeX RIS

Luc Lemaire, John C Wood. 2007-12-20. Jacobi fields along harmonic 2-spheres in $S^3$ and $S^4$ are not all integrable. https://arxiv.org/abs/0709.1417

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