CAT(0) metrics on contractible manifolds

Karim A. Adiprasito; Louis Funar

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arXiv · 1512.06403

CAT(0) metrics on contractible manifolds

Karim A. Adiprasito·Louis Funar

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Abstract

We prove that an open manifold $M$ of dimension at least $5$ which admits a complete CAT(0) polyhedral metric is pseudo-collarable, its fundamental group at infinity is strongly perfectly semistable and has vanishing Chapman-Siebenmann obstruction $\tau_{\infty}(M)$. Moreover, this implies that $M$ is topologically collapsible, when $n\geq 6$. Conversely, any finite dimensional collapsible polyhedron is PL homeomorphic to a CAT(0) cubical complex.

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Karim A. Adiprasito, Louis Funar. 2015-12-20. CAT(0) metrics on contractible manifolds. https://arxiv.org/abs/1512.06403

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