Log-concavity conjecture for marginals of the sine process

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Consider a determinantal point process on the real line with correlation kernel

K(x,y)=sin⁡(π(y−x))y−x.K(x,y)=\frac{\sin(\pi(y-x))}{y-x}.

Label its points by ⋯<Z−1<Z0<Z1<Z2<⋯\cdots<Z_{-1}<Z_0<Z_1<Z_2<\cdots so that Z−1<0≤Z0Z_{-1}<0\leq Z_0. The sine-process marginal conjecture. For every sub-collection (Zi1,…,Zik)(Z_{i_1},\ldots,Z_{i_k}), its marginal density on Rk\mathbb{R}^k is log-concave. The conjecture is motivated by the log-concavity of marginals for uniform Gelfand–Tsetlin functions and the identification of bead-process marginals with the sine process; the source presents it as unresolved.

References

Primary source

Samuel G. G. Johnston and Joscha Prochno, “The macroscopic shape of Gelfand-Tsetlin patterns and free probability”, arXiv:2410.10754 (2026).

Progress summary

Refreshed
Open

The conjecture remains open: no public proof, counterexample, or substantive advance has been found.

The conjecture asks whether every finite selection of points from the sine process has a log-concave joint density. The directly relevant source, from October 2024, presents the question as unresolved; no proposer or later resolution is recorded.

Current status (as of September 2026): The conjecture remains open, with no publicly recorded proof, counterexample, or substantive progress.

Sources

Solutions 0

No solutions have been posted yet.