2 00 7 Manifolds admitting a G̃ 2 - structure
نویسنده
چکیده
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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تاریخ انتشار 2009