OpenAI says an internal model produced a solution to the Navier-Stokes Millennium Prize problem

OpenAI published an analytical proof and a Lean formalization that a smooth 3D fluid under a smooth external force can develop a finite-time singularity, which it says establishes statements C and D of the official Millennium Prize formulation. The proof came from a coordinating swarm of about 10,000 agents over 88 hours, powered by an internal model described as significantly more capable than GPT-6 Astra, with 17 more hours of Lean verification. OpenAI says it will not claim the Clay prize, and it acknowledges concurrent priority work on forced Euler by mathematicians Tristan Buckmaster and Levent Alpoge, who accuse OpenAI of scooping work they had pursued for nearly a year; OpenAI says it cannot rule out that de-identified usage data helped improve the model.