How Long Is Fermat's Last Theorem in Lean?
Alex Kontorovich says the Lean formalization of Fermat's Last Theorem is 13 million lines. He was sure that formalization was at least three years away.
He had just told a colloquium in the Princeton mathematics department that current systems build one or two layers on Mathlib and are weak at canonization, the cleanup that puts a lemma where it belongs in the library. A manuscript that pulls many areas together sat outside that halo. The statement of Fermat's Last Theorem is elementary, so there is no hidden meaning to check, and Lean reports the proof sorry-free. Whole textbooks formalize when they sit one or two steps from Mathlib. Three or four steps out, definitions made for different purposes clash and will not stitch back together.
#503 – AI Crisis in Math: Navier-Stokes, Riemann Hypothesis & Complexity Theory ·