The b-conjecture and Airyβ soft-edge limit for the Jack–Plancherel process

For every β>0\beta>0, the standard edge-scaled Jack–Plancherel process converges at the soft edge, in its multi-time finite-dimensional statistics (in particular, in moments), to the corresponding Airyβ_\beta process. Equivalently, for every finite collection of times t1,…,tkt_1,\ldots,t_k and every admissible polynomial test function PP, one has lim⁡n→∞E ⁣[P ⁣(Xn(β)(t1),…,Xn(β)(tk))]=E ⁣[P ⁣(Aβ(t1),…,Aβ(tk))]\lim_{n\to\infty}\mathbb{E}\!\left[P\!\left(X_n^{(\beta)}(t_1),\ldots,X_n^{(\beta)}(t_k)\right)\right]=\mathbb{E}\!\left[P\!\left(\mathcal{A}_\beta(t_1),\ldots,\mathcal{A}_\beta(t_k)\right)\right], where Xn(β)X_n^{(\beta)} is the edge-scaled Jack–Plancherel process and Aβ\mathcal{A}_\beta is the Airyβ_\beta process.

References

Primary source

arXiv

Progress summary

Refreshed
Claimed progress

A September 2026 paper proves major limit theorems for this random-partition model, but does not claim to settle every version of the conjecture.

The problem concerns whether the Jack–Plancherel process has an Airy soft-edge limit and yields the predicted expansion associated with the bb-conjecture. The latest paper links this discrete model to Airy processes and develops the relevant asymptotic formulas.

Known results

  • Féray and Dołęga proved the law of large numbers and central limit theorem for Jack–Plancherel measure.
  • Féray and Dołęga conjectured the edge scaling limit.
  • Guionnet and Huang later proved that the edge limit is governed by the β\beta-Tracy–Widom law.

September 2026 progress

The paper establishes multi-time moment convergence, identifies the equal-time limit with Airyβ\beta statistics for β≥1\beta \ge 1, and derives an asymptotic β\beta-topological expansion, including a nonnegative β=2\beta=2 formula for Witten–Kontsevich intersection numbers. This is substantial progress, but the abstract does not claim a complete resolution of every formulation of the bb-conjecture; the claims remain unverified here.

Current status (as of September 2026): Major soft-edge and expansion results are claimed, while a complete resolution of the bb-conjecture remains open or unestablished.

Sources

Solutions 0

No solutions have been posted yet.