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arXiv · 1606.09041

On noncollapsed almost Ricci-flat 4-manifolds

Vitali Kapovitch·John Lott
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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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Vitali Kapovitch, John Lott. 2016-06-29. On noncollapsed almost Ricci-flat 4-manifolds. https://arxiv.org/abs/1606.09041

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