A 100-year-old conjecture was proved false on a laptop during the World Cup final. Anthropic's Levent Alpoge used Claude Fable 5 to find a three-dimensional counterexample disproving the Jacobian conjecture - we break down what the Jacobian actually is (in Google Maps terms) and why Anthropic is the only lab that can see whether Claude was brilliant or lucky.
Then: 50 companies including Nvidia, Microsoft, Meta, and a16z signed the Open Weights letter telling Washington hands off, OpenAI and Google quietly added their names a day later, and Anthropic is the lone holdout - while reportedly lobbying DC to restrict Chinese weights the whole time. Plus we do the math on the Kimi K3 distillation timeline: Fable 5 was live for 18 days before K3 shipped, so how much Claude is realistically in there?
What is Pretrained?
Everyone's talking about AI but most of it is hype, jargon, or someone trying to sell you something. Pierce Freeman and Richard Diehl Martinez are two Stanford friends who actually work in this space with nothing to sell you but good vibes. We'll make you smarter - and you might actually enjoy it.