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arXiv · 1511.08557

An upper bound for the pseudoisotopy stable range

Oscar Randal-Williams
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Abstract

We prove that the pseudoisotopy stable range for manifolds of dimension 2n can be no better than (2n-2). In order to do so, we define new characteristic classes for block bundles, extending our earlier work with Ebert, and prove their non-triviality. We also explain how similar methods show that Top(2n)/O(2n) is rationally (4n-5)-connected.

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Oscar Randal-Williams. 2016-11-21. An upper bound for the pseudoisotopy stable range. https://arxiv.org/abs/1511.08557

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