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arXiv · 2308.15971

Harmonic Morphisms on Lie groups and Minimal Conformal Foliations of Codimension two

Sigmundur Gudmundsson·Thomas Jack Munn
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Abstract

Let G be a Lie group equipped with a left-invariant semi-Riemannian metric. Let K be a semisimple subgroup of G generating a left-invariant conformal foliation F of codimension two on G. We then show that the foliation F is minimal. This means that locally the leaves of F are fibres of a complex-valued harmonic morphism. In the Riemannian case, we prove that if the metric restricted to K is biinvariant then F is totally geodesic.

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Sigmundur Gudmundsson, Thomas Jack Munn. 2023-08-30. Harmonic Morphisms on Lie groups and Minimal Conformal Foliations of Codimension two. https://arxiv.org/abs/2308.15971

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