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Isomorphism Between Dual and Standard Artin Groups

Determine whether, for every Coxeter group W and Coxeter element w, the dual Artin group G^*_{W, w} defined from the noncrossing partition poset NC(W, w) via the dual presentation on reflections R_0 is isomorphic to the standard Artin group G_W associated to W.

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Background

The dual presentation constructs G*_{W, w} using maximal chains in NC(W, w) with generators given by reflections labeling cover relations. Bessis proved the isomorphism G*_{W, w} \cong G_W in spherical cases, and McCammond and Sulway established it in affine cases; it has also been confirmed for rank-three cases.

A uniform understanding across all Coxeter groups would clarify the relationship between combinatorial dual structures and classical Artin presentations, with implications for group theory and topology.

References

A key open question in the theory of Artin groups is the following: Is every dual Artin group $G*_{W, w}$ isomorphic to the corresponding standard Artin group $G_W$?

The $K(π, 1)$ conjecture for affine Artin groups (2509.00445 - Paolini et al., 30 Aug 2025) in Section 3 (The algebraic side: dual Artin groups)