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The existence of closed 3-forms of $\tilde G_2$-type on 7-manifolds

Hong-Van Le
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Abstract

In this note we construct a first example of a closed 3-form of $\tilde G_2$-type on $S^3\times S^4$. We prove that $S^3\times S^4$ does not admit a homogeneous 3-form of $\tilde G_2$-type. Thus our example is a first example of a closed 3-form of $\tilde G_2$-type on a compact 7-manifold which is not stably homogeneous.

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Hong-Van Le. 2008-05-03. The existence of closed 3-forms of $\tilde G_2$-type on 7-manifolds. https://arxiv.org/abs/math/0603182

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