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arXiv · 2607.21420

Homotopy types of intervals in corank-three higher Bruhat orders

Daria Poliakova
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Abstract

We prove Reiner's conjecture for higher Bruhat orders in corank 3: the facial intervals of B(n,n-3) are precisely the spherical intervals, and all other intervals are contractible.

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Daria Poliakova. 2026-07-23. Homotopy types of intervals in corank-three higher Bruhat orders. https://arxiv.org/abs/2607.21420

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