Some new examples with almost positive curvature

Kerin, Martin¹

¹ Mathematisches Institut, Fachbereich Mathematik und Informatik der Universität Münster, Einsteinstrasse 62, D-48149 Münster, Germany

Geometry & topology, Tome 15 (2011) no. 1, pp. 217-260.

Résumé

As a means to better understanding manifolds with positive curvature, there has been much recent interest in the study of nonnegatively curved manifolds which contain points at which all $2$–planes have positive curvature. We show that there are generalisations of the well-known Eschenburg spaces and quotients of $S^7\times S^7$ which admit metrics with this property.

Détail

DOI : 10.2140/gt.2011.15.217

Keywords: biquotient, positive curvature, Pontrjagin class

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