Nikolov-Ullman Pure-DP Query Release Conjecture
Nikolov and Ullman asked, as Open Problem 1 on DifferentialPrivacy.org, whether statistical queries over a universe of size can be released under pure differential privacy at the square-root error rate that the known lower bounds suggest, rather than the cube-root rate of the classical small-database method. They can: for every and there is an -differentially private mechanism with expected error .
- Result
- Proved(see note)
- Status
- Resolved
- AI contribution
- AI-assisted
- Method
- Argument
- Field
- Differential privacy
- Posed by
- Aleksandar Nikolov, Jonathan Ullman
- Year posed
- —
- Years open
- —
- Solved
- 2026-07-22
- Model
- Codex, Harmonic Aristotle
- Vendor
- OpenAI / Harmonic
- Collaborators
- Jack Fitzsimons
- Verification
- Unreviewed
- Publication
- Preprint
- Significance
- 20 / 100
- Disclosed cost
- —
- Wikipedia
- No dedicated article
What was actually shown
information-theoretic; a polynomial-time implementation remains open
What the AI did
The generative-AI disclosure states that Codex and Aristotle were used in connection with Lean formalization and proof search, and that Codex also gave editorial feedback on clarity and organization. Proof search is a mathematical contribution, but the disclosure does not say which steps came from where.
Verification
Single-author arXiv preprint with a companion Lean 4 development that the paper says machine-checks the finite construction, pure privacy after deterministic decoding, and the all-regimes upper bound, with an axiom audit and a paper-to-Lean crosswalk in the artifact. We have not compiled it. Not yet peer-reviewed.
Source
arXiv:2607.20418 - Pure-DP Statistical Query Release at the Conjectured Square-Root Rate