Nonnegative Curvature, Symmetry and Fundamental Group
نویسندگان
چکیده
منابع مشابه
Nonnegative curvature, symmetry and fundamental group
We prove a result on equivariant deformations of flat bundles, and as a corollary, we obtain two “splitting in a finite cover” theorems for isometric group actions on Riemannian manifolds with infinite fundamental groups, where the manifolds are either compact of Ric ≥ 0, or complete of sec ≥ 0.
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Gromov conjectured that the fundamental group of a manifold with almost nonnegative Ricci curvature is almost nilpotent. This conjecture is proved under the additional assumption on the conjugate radius. We show that there exists a nilpotent subgroup of finite index depending on a lower bound of the conjugate radius.
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ژورنال
عنوان ژورنال: Geometriae Dedicata
سال: 2004
ISSN: 0046-5755
DOI: 10.1023/b:geom.0000033839.94207.d1