Classification of manifolds with weakly 1/4-pinched curvatures
- First Online:
- Cite this article as:
- Brendle, S. & Schoen, R.M. Acta Math (2008) 200: 1. doi:10.1007/s11511-008-0022-7
We show that a compact Riemannian manifold with weakly pointwise 1/4-pinched sectional curvatures is either locally symmetric or diffeomorphic to a space form. More generally, we classify all compact, locally irreducible Riemannian manifolds M with the property that M × R2 has non-negative isotropic curvature.