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arXiv · 2308.15607

The Alexander trick for homology spheres

Soren Galatius·Oscar Randal-Williams
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Abstract

We show that the group of homeomorphisms of a compact contractible $d$-manifold which fix the boundary is contractible, as long as $d \geq 6$. We deduce this from a strong uniqueness statement for one-sided $h$-cobordisms.

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Soren Galatius, Oscar Randal-Williams. 2024-11-04. The Alexander trick for homology spheres. https://arxiv.org/abs/2308.15607

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