Abstract
In the first part of this note we study compact Riemannian manifolds (M, g) whose Riemannian product with \({\mathbb{R}}\) is conformally Einstein. We then consider 6-dimensional almost Hermitian manifolds of type W 1 + W 4 in the Gray–Hervella classification admitting a parallel vector field and show that (under some mild assumption) they are obtained as Riemannian cylinders over compact Sasaki–Einstein 5-dimensional manifolds.
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Moroianu, A., Ornea, L. Conformally Einstein products and nearly Kähler manifolds. Ann Glob Anal Geom 33, 11–18 (2008). https://doi.org/10.1007/s10455-007-9071-y
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DOI: https://doi.org/10.1007/s10455-007-9071-y