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arXiv · 1511.08930

Formality of 7-dimensional 3-Sasakian manifolds

Marisa Fernández·Stefan Ivanov·Vicente Muñoz
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Abstract

We prove that any simply connected compact 3-Sasakian manifold, of dimension seven, is formal if and only if its second Betti number is $b_2<2$. In the opposite, we show an example of a 7-dimensional Sasaki-Einstein manifold, with second Betti number $b_2\geq 2$, which is formal. Therefore, such an example does not admit any 3-Sasakian structure. Examples of 7-dimensional simply connected compact formal Sasakian manifolds, with $b_2\geq 2$, are also given.

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Marisa Fernández, Stefan Ivanov, Vicente Muñoz. 2015-11-28. Formality of 7-dimensional 3-Sasakian manifolds. https://arxiv.org/abs/1511.08930

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