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Harmonic maps in unfashionable geometries

F. E. Burstall·U. Hertrich-Jeromin
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Abstract

We describe some general constructions on a real smooth projective 4-quadric which provide analogues of the Willmore functional and conformal Gauss map in both Lie sphere and projective differential geometry. Extrema of these functionals are characterized by harmonicity of this Gauss map.

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F. E. Burstall, U. Hertrich-Jeromin. 2001-03-26. Harmonic maps in unfashionable geometries. https://doi.org/10.1007/s002290200269

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