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Coxeter-generalization: homotopy equivalence of the branched annulus complex to the orbit configuration space

Show that for any Coxeter group W and Coxeter element δ ∈ W, the bisimplicial complex Br_{W,δ}^{m}(closed annulus) is homotopy equivalent to its interior, which is homeomorphic to the orbit configuration space Y_W.

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Background

The authors extend their polynomial constructions from the symmetric group case to general Coxeter groups by introducing a bisimplicial complex Br_{W,δ}{m}(closed annulus), built from algebraic labels related to Coxeter factorizations. They conjecture that this compactification captures the homotopy type of the orbit configuration space Y_W.

If proven, this would bridge the dual Artin group A_{W,δ}* and the standard Artin group A_W, and—under additional compactification hypotheses—could imply their isomorphism, advancing the K(π,1) program for Artin groups.

References

\begin{conj}\label{conj:dual-artin-groups} Let $W$ be a Coxeter group and let $\delta \in W$ be a Coxeter element. Then the bisimplicial complex $Br_{W,\delta}{m}(\closedannulus)$ is homotopy equivalent to its interior, which is homeomorphic to the orbit configuration space $Y_W$. \end{conj}

Geometric Combinatorics of Polynomials II: Polynomials and Cell Structures (2410.03047 - Dougherty et al., 4 Oct 2024) in Generalizations and conjectures; Conjecture (label 'conj:dual-artin-groups')