The collapsing geometry of almost Ricci-flat 4-manifolds

John Lott

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arXiv · 1708.06780

The collapsing geometry of almost Ricci-flat 4-manifolds

John Lott

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Abstract

We consider Riemannian 4-manifolds that Gromov-Hausdorff converge to a lower dimensional limit space, with the Ricci tensor going to zero. Among other things, we show that if the limit space is two dimensional then under some mild assumptions, the limiting four dimensional geometry away from the curvature blowup region is semiflat Kaehler.

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John Lott. 2017-08-22. The collapsing geometry of almost Ricci-flat 4-manifolds. https://arxiv.org/abs/1708.06780

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