An 87‑year‑old math conjecture may have just collapsed and it happened during the World Cup final. ⚽📐 Mathematician Akhil Mathew raised the Jacobian conjecture problem, first proposed in 1939. Levent Alpöge then reported that Anthropic’s Claude Fable 5 produced an explicit counterexample. The conjecture claimed that any polynomial map with a constant, nonzero Jacobian determinant must have a polynomial inverse. But this new map keeps its determinant fixed at −2 while sending three different inputs to the same output. That collision means it cannot be reversed. This wasn’t just a claim Alpöge published the full formula, making it directly testable with symbolic algebra. Mathematicians quickly began verifying the determinant and the three matching outputs. If the counterexample holds, it disproves the Jacobian conjecture in three variables and every higher dimension. The two‑variable case would remain open. An AI model may have helped overturn nearly nine decades of mathematic...