Coherence and negative sectional curvature in complexes of groups
نویسندگان
چکیده
منابع مشابه
Negative sectional curvature and the product complex structure
Let M = M1 ×M2 be a product of complex manifolds. We prove that M cannot admit a complete Kähler metric with sectional curvature K < c < 0 and Ricci curvature Ric > d, where c and d are arbitrary constants. In particular, a product domain in Cn cannot cover a compact Kähler manifold with negative sectional curvature. On the other hand, we observe that there are complete Kähler metrics with nega...
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Manifolds with non-negative sectional curvature have been of interest since the beginning of global Riemannian geometry, as illustrated by the theorems of Bonnet-Myers, Synge, and the sphere theorem. Some of the oldest conjectures in global Riemannian geometry, as for example the Hopf conjecture on S × S, also fit into this subject. For non-negatively curved manifolds, there are a number of obs...
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ژورنال
عنوان ژورنال: Michigan Mathematical Journal
سال: 2013
ISSN: 0026-2285
DOI: 10.1307/mmj/1378757886