منابع مشابه
Pontryagin Numbers and Nonnegative Curvature
We prove that any rational linear combination of Pontryagin numbers that is not a multiple of the signature is unbounded on connected closed oriented manifolds of nonnegative sectional curvature. Combining our result with Gromov’s finiteness result for the signature yields a new characterization of the L-genus.
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The purpose of this survey is to give an overview of the results which characterize Riemannian manifolds with nonnegative or positive sectional, Ricci and scalar curvature, putting an emphasis on the differences between these increasingly strong conditions on curvature. All manifolds considered here are assumed to be complete. First we consider how nonnegative curvature is different from positi...
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ژورنال
عنوان ژورنال: Mathematische Annalen
سال: 2016
ISSN: 0025-5831,1432-1807
DOI: 10.1007/s00208-016-1457-3