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arXiv · 2011.01320

Hyperbolization and regular neighborhoods

Igor Belegradek
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Abstract

We show that the hyperbolization of polyhedra pulls back regular neighborhoods of PL submanifolds. Applying this to the Riemannian version of the hyperbolization due to Ontaneda gives open complete manifolds of pinched negative curvature that are homotopy equivalent to closed smooth manifolds but contain no smooth spines. We also find open complete negatively pinched manifolds that are homotopy equivalent to closed non-smoothable manifolds.

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Igor Belegradek. 2020-11-02. Hyperbolization and regular neighborhoods. https://arxiv.org/abs/2011.01320

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