The existence of closed 3 - forms of G̃ 2 - type on 7 - manifolds ∗
نویسنده
چکیده
In this note we construct a first example of a closed 3-form of G̃2-type on S 3 × S. We prove that S × S does not admit a homogeneous 3-form of G̃2-type. Thus our example is a first example of a closed 3-form of G̃2-type on a compact 7-manifold which is not stably homogeneous.
منابع مشابه
2 00 7 Manifolds admitting a G̃ 2 - structure
We find a necessary and sufficient condition for a compact 7-manifold to admit a G̃2-structure. As a result we find a sufficient condition for an open 7-manifold to admit a closed 3-form of G̃2-type.
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