Four-root-of-unity anti-concentration conjecture

About 4 years old · traced to

Let ξ1,ξ2,ξ3,ξ4\xi_1,\xi_2,\xi_3,\xi_4 be independent random variables, each uniformly distributed on the set of nnth roots of unity.

Four-root-of-unity anti-concentration conjecture. As n→∞n\to\infty,

P(∣Re⁡(ξ1+ξ2+ξ3+ξ4)∣<1n2)=1n2+o(1).\mathbb{P}\left(\left|\operatorname{Re}(\xi_1+\xi_2+\xi_3+\xi_4)\right|<\frac{1}{n^2}\right)=\frac{1}{n^{2+o(1)}}.

The conjecture is presented as an obstacle to proving regularity of the unperturbed eigenvalues without uniform boundary conditions. The source gives no resolution, so its status remains open.

References

Primary source

András Mészáros and Bálint Virág, “Eigenvectors of the square grid plus GUE”, arXiv:2212.09614 (2023).

Progress summary

Refreshed
Open

No public discussion or published progress appears to have changed this conjecture's open status.

No public discussion or published progress on this conjecture was found.

Current status (as of August 2026): the conjecture appears open, with no recorded public activity.

Solutions 0

No solutions have been posted yet.