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arXiv · 2610.02073

Quasi-contact metric structures from Sasaki-Einstein metrics

Beniamino Cappelletti-Montano·Antonio De Nicola
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Abstract

We construct the first examples of quasi-contact metric structures that are not contact metric in every odd dimension greater than or equal to $5$. In dimension $5$, we construct a one-parameter family of such examples with a Killing characteristic vector field by deforming Sasaki-Einstein $\mathrm{SU}(2)$-structures. This yields compact, homogeneous examples on $S^5$. In arbitrary dimensions, we investigate quasi-contact metric structures with a Killing characteristic vector field and derive a Ricci curvature criterion for the structure to be K-contact.

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Beniamino Cappelletti-Montano, Antonio De Nicola. 2026-10-01. Quasi-contact metric structures from Sasaki-Einstein metrics. https://arxiv.org/abs/2610.02073

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