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A class of nonsymmetric harmonic Riemannian spaces

Ewa Damek·Fulvio Ricci
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Abstract

Certain solvable extensions of $H$-type groups provide noncompact counterexamples to the so-called Lichnerowicz conjecture, which asserted that ``harmonic'' Riemannian spaces must be rank 1 symmetric spaces.

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Ewa Damek, Fulvio Ricci. 1992-07-01. A class of nonsymmetric harmonic Riemannian spaces. https://arxiv.org/abs/math/9207213

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