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Positive Quaternionic Kaehler manifolds and symmetry rank: II

Fuquan Fang
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Abstract

Let M be a positive quaternionic Kaehler manifold of dimension 4m. If the isometry group Isom(M) has rank at least m/2 +3, then M is isometric to HP^m or Gr_2(C^{m+2}). The lower bound for the rank is optimal if m is even.

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Fuquan Fang. 2005-04-26. Positive Quaternionic Kaehler manifolds and symmetry rank: II. https://arxiv.org/abs/math/0402124

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