Acyclicity conjecture for graphs of affine reversal sets

Let wS~nw\in \widetilde{\mathfrak{S}}_n, let Cw(n,k)\mathcal{C}_w(n,k) denote the relevant collection of consistent subsets, and let RCw(n,k)R\in \mathcal{C}_w(n,k). Define GRG_R by including edges XYX\to Y whenever X<Pw(n,k)YX<_{\mathcal{P}_w(n,k)}Y is a congruence relation. Acyclicity conjecture. For any RCw(n,k)R\in \mathcal{C}_w(n,k), the graph GRG_R is acyclic. This is the obstruction identified in the source to proving a complete affine analogue of the corresponding nonlongest-permutation result; the source reports computational verification for 1k81\leq k\leq 8 and affine permutations of bounded lengths, but gives no general proof.

Sources & referencesView supporting material

Primary source

Sara Billey, Herman Chau and Kevin Liu, “Commutation classes of reduced words and higher Bruhat orders for affine permutations”, arXiv:2604.24573 (2026).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.