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arXiv · 1504.00255

Three new almost positively curved manifolds

Jason DeVito
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Abstract

A Riemannian manifold is called almost positively curved if the set of points for which all $2$-planes have positive sectional curvature is open and dense. We find three new examples of almost positively curved manifolds: $Sp(3)/Sp(1)^2$, and two circle quotients of $Sp(3)/Sp(1)^2$. We also show the quasi-positively curved metric of Tapp [26]} on $Sp(n+1)/Sp(n-1) Sp(1)$ is not almost positively curved if $n\geq 3$.

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Jason DeVito. 2015-04-01. Three new almost positively curved manifolds. https://arxiv.org/abs/1504.00255

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