The normal homogeneous space (𝖲𝖴(3)×𝖲𝖮(3))/𝖴^{∙}(2) has positive sectional curvature

Wilking, Burkhard

doi:10.1090/S0002-9939-99-04613-4

The normal homogeneous space ${\bigl (\mathsf {SU}(3)\times \mathsf {SO}(3)\bigr )/\mathsf {U}^{\bullet }(2)}$ has positive sectional curvature
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Proc. Amer. Math. Soc. 127 (1999), 1191-1194 Request permission

Abstract:

We give a new description of the positively curved seven-dimensional Aloff-Wallach spaces $M^7_{kl}$. In particular, this description exhibits $M^7_{11}$ as a normal homogeneous space, although it does not occur in Berger’s classification (1961).

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