According to an OpenAI blog post published Tuesday, the agents arrived at the result on September 5, after 88 hours of computation, using approximately 130 billion output tokens for the Navier-Stokes problem alone. The proof has been formally checked in the programming language Lean, lending mathematical confidence to the result.
But the announcement came just 12 hours after Buckmaster published a preprint of his own AI-assisted findings on related problems, accompanied by a statement detailing a fraught exchange with OpenAI. Buckmaster said he and Alpöge had worked on the problem for nearly a year, using Claude and OpenAI's Codex. After a breakthrough on August 15, rumors spread that a major problem had been solved. Buckmaster said OpenAI admitted to launching its own effort on September 1 — after hearing those rumors.
"I asked when the first prompt had been sent by them. This question was not answered directly by OpenAI for some time. Eventually it was agreed that it had been sent in the past few days, after information about our work had reached OpenAI," Buckmaster wrote.
OpenAI's blog post acknowledged the timing: "On Tuesday, September 1, we heard rumors that two Millennium Prize problems had been resolved. Inspired by these rumors and by the step change in performance of our internal model, we launched an effort."
OpenAI offered to wait for Buckmaster to publish or to have him co-author a paper on their result. However, they made clear that Alpöge would not be included as a co-author, citing OpenAI's competitive relationship with Anthropic.