Polynomial Littlewood–Offord conjecture

For every fixed integer d≥1d\ge 1, there exists a constant Cd>0C_d>0 such that the following holds. If F:Rn→RF:\mathbb{R}^n\to\mathbb{R} is a degree-dd multilinear polynomial containing rr degree-dd monomials whose sets of variables are pairwise disjoint, and ξ1,…,ξn\xi_1,\ldots,\xi_n are independent Rademacher random variables, then P[F(ξ1,…,ξn)=0]≤Cdr−1/2\mathbb{P}\bigl[F(\xi_1,\ldots,\xi_n)=0\bigr]\le C_d r^{-1/2}; equivalently, P[F(ξ1,…,ξn)=0]=Od(r−1/2)\mathbb{P}\bigl[F(\xi_1,\ldots,\xi_n)=0\bigr]=O_d(r^{-1/2}).

References

Primary source

arXiv

Additional references

Progress summary

Refreshed
Claimed solved

A new manuscript claims to remove the last known logarithmic loss and settle the conjecture, but its proof has not been independently checked.

The conjecture seeks the optimal anti-concentration bound for random evaluations of polynomials. The general case was previously known only with a logarithmic or subpolynomial loss, while the linear and quadratic cases were understood more completely.

Known results

  • The optimal-order bound is known for degrees d=1d=1 and d=2d=2; general dd previously incurred a factor (log⁡b)Od(1)(\log b)^{O_d(1)} (Kane; Meka, Nguyen, and Vu).
  • Kwan, Sah, and Sawhney disproved Costello's original stronger conjecture for d≥3d\ge 3.
  • The repaired conjecture is proved for dd-multilinear forms, and partial bounds are known for complex quadratics and high-rank quadratic parts.
  • A quadratic robust-dependence theorem gives an upper bound of order m−1/2m^{-1/2} under its stated hypothesis.

October 2026 claimed resolution

On October 6, 2026, Alexandr Grebennikov's manuscript Optimal bound for the polynomial Littlewood-Offord problem claimed removal of the polylogarithmic factor for polynomials containing rr disjoint degree-dd monomials, which would settle the stated conjecture and a related total-influence conjecture. The manuscript credits GPT-6 Pro, but the claim is unrefereed and has no independent mathematical corroboration in the retrieved evidence.

Current status (as of October 2026): The general conjecture remains unverified; the latest manuscript claims a complete proof, while established results cover important special cases and prior bounds with losses.

  • GPT-6 ProOpenAIsolved2026-10-06evidence

    Claimed optimal polynomial Littlewood–Offord bound

Sources

Solutions 0

No solutions have been posted yet.