Oct 6, 2026
Lean formalization in OpenAI math repository (Result 213)
Model / AI: OpenAI (unreleased)
machine-checked (formal proof)self-reported (formal proof)
OpenAI's internal frontier model proved and formalized in Lean the main result of 'Critical bond and site percolation on the cubic lattice'. We prove that nearest-neighbor Bernoulli bond and site percolation on ℤ3 have no infinite cluster at their respective critical parameters. The proof combines a finite connection inequality for independent hyperedges with a finite-scale extension estimate and an adaptive exploration.
Source read 2026-10-08. Cataloged from OpenAI's formalization.yaml (Family 213). The Lean development was not rebuilt locally.