1 3 Ju l 2 00 1 Stable forms and special metrics Nigel Hitchin
نویسندگان
چکیده
We show how certain diffeomorphism-invariant functionals on differential forms in dimensions 6, 7 and 8 generate in a natural way special geometrical structures in these dimensions: metrics of holonomy G2 and Spin(7), metrics with weak holonomy SU(3) and G2, and a new and unexplored example in dimension 8. The general formalism becomes a practical tool for calculating homogeneous or cohomogeneity one examples, and we illustrate this with some newly discovered examples of Spin(7) and G2 metrics.
منابع مشابه
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