On noncollapsed almost Ricci-flat 4-manifolds

2016/06/29 by Kapovitch, Vitali, Lott, John
#Differential Geometry (math.DG) #FOS: Mathematics

paper · doi:10.48550/arxiv.1606.09041

Abstract

We give topological conditions to ensure that a noncollapsed almost Ricci-flat 4-manifold admits a Ricci-flat metric. One sufficient condition is that the manifold is spin and has a nonzero A-hat genus. Another condition is that the fundamental group is infinite or, more generally, of sufficiently large cardinality.

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