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A Suspension Lemma for Bounded Posets

Jörg Rambau
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Abstract

Let $P$ and $Q$ be bounded posets. In this note, a lemma is introduced that provides a set of sufficient conditions for the proper part of $P$ being homotopy equivalent to the suspension of the proper part of~$Q$. An application of this lemma is a unified proof of the sphericity of the higher Bruhat orders under both inclusion order (a known proved earlier by Ziegler) and single step inclusion order (which was not previously known).

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Jörg Rambau. 1997-03-27. A Suspension Lemma for Bounded Posets. https://arxiv.org/abs/math/9703212

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