Fundamental Groups of Manifolds of Positive Sectional Curvature and Bounded Covering Geometry

Abstract

Let $M$ be an $n$-manifold of positive sectional curvature $≥ 1.$ In this paper, we show that if the Riemannian universal covering has volume at least $v > 0,$ then the fundamental group $\pi_1(M)$ has a cyclic subgroup of index bounded above by a constant depending only on $n$ and $v.$