Sphere theorem
= Sphere theorem
{wiki=Sphere_theorem}
The Sphere Theorem is a result in differential geometry that describes the geometric properties of manifolds with certain curvature conditions. Specifically, it pertains to the behavior of Riemannian manifolds that have non-negative sectional curvature. The Sphere Theorem states that if a Riemannian manifold has non-negative sectional curvature and is simply connected, then it is homeomorphic to a sphere.