3 problems

Let $M$ be a positive quaternionic Kähler manifold of dimension $8m+4$, and let $\operatorname{rank}(M)$ denote the rank of its isometry group. Improved symmetry-rank conjecture. I…

A quaternionic-Kähler manifold is a Riemannian manifold with holonomy contained in the quaternionic unitary group, and it has positive scalar curvature when its scalar curvature is…

A quaternionic Kähler manifold is a Riemannian manifold whose holonomy is contained in $\operatorname{Sp}(n)\operatorname{Sp}(1)$; its scalar curvature is positive when its scalar-…