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Harmonic morphisms from the classical non-compact semisimple Lie groups

Sigmundur Gudmundsson·Anna Sakovich
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Abstract

We construct the first known complex valued harmonic morphisms from the non-compact Lie groups SL(n,R), SU*(2n) and Sp(n,R) equipped with their standard Riemannian metrics. We then introduce the notion of a bi-eigenfamily and employ this to construct the first known solutions on the non-compact Riemannian SO*(2n), SO(p,q), SU(p,q) and Sp(p,q). Applying a duality principle we then show how to manufacture the first known complex valued harmonic morphisms from the compact Lie groups SO(n), SU(n) and Sp(n) equipped with semi-Riemannian metrics.

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Sigmundur Gudmundsson, Anna Sakovich. 2007-03-13. Harmonic morphisms from the classical non-compact semisimple Lie groups. https://arxiv.org/abs/math/0701520

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