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Harmonic morphisms between degenerate semi-Riemannian manifolds

Alberto Pambira
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Abstract

In this paper we generalize harmonic maps and morphisms to the \emph{degenerate semi-Riemannian category}, in the case when the manifolds $M$ and $N$ are \emph{stationary} and the map $ϕ:M\to N$ is \emph{radical-preserving}. We characterize geometrically the notion of \emph{(generalized) horizontal (weak) conformality} and we obtain a characterization for (generalized) harmonic morphisms in terms of (generalized) harmonic maps.

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Alberto Pambira. 2003-03-21. Harmonic morphisms between degenerate semi-Riemannian manifolds. https://arxiv.org/abs/math/0303275

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