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The maximum symmetry metric on real projective space $ \mathbb{RP}^n $ is the round metric.

The maximum symmetry metric on complex projective space $ \mathbb{CP}^n $ is the Fubini-Study metric.

https://mathoverflow.net/questions/433847/maximum-symmetry-metric-on-mathbbcpn

Let $ M $ be a compact connected manifold. The degree of symmetry of $ M $, denoted $ N(M) $, is the maximum of the dimensions of the isometry groups of all possible Riemannian structures on $ M $. See for example

https://www.ams.org/journals/tran/1969-146-00/S0002-9947-1969-0250340-1/S0002-9947-1969-0250340-1.pdf

Two metrics are considered to be equivalent if they are isometric up to a constant multiple.

I'm interested in manifolds $ M $ for which there is a unique up to equivalence metric with isometry group of dimension $ N(M) $.

Is the pushforward of the biinvariant metric of $ F_4 $ onto the Cayley projective plane $$ \mathbb{OP}^2 \cong F_4/Spin(9) $$ a maximum symmetry metric in this sense?

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