Jul 21, 2026
ManyPress
Science

Harvard mathematician Levent Alpöge has used AI to provide a counterexample to the Jacobian conjecture, a long-standing mathematical problem first proposed in 1939.

ManyPress

ManyPress

ManyPress Editorial

3 min readSource:New Scientist Reviewed by editors
Mathematician uses AI to disprove 87-year-old Jacobian conjecture

Key facts

  • The Jacobian conjecture was included on a list of 18 difficult mathematical problems for the 21st century compiled by Stephen Smale in 1998.
  • Alpöge credited the AI model Claude Fable 5 for assisting with the work during the World Cup final.
  • The counterexample provided by Alpöge consists of a single line of mathematics that is 216 characters long.
  • Abhishek Saha stated that this is likely the most significant conjecture AI has played a role in addressing to date.
  • The discovery has raised questions about the future necessity of human mathematicians as AI capabilities in the field continue to advance.

Levent Alpöge, a mathematician at Harvard University, announced on July 19 that he has disproven the Jacobian conjecture. Alpöge shared a 216-character counterexample on X, crediting his work to the AI model Claude Fable 5, developed by Anthropic. The conjecture, which suggested that specific mathematical functions could operate in reverse, had remained unproven since it was formally introduced by Ott-Heinrich Keller in 1939.

Significance of the discovery

Experts in the field consider this the most difficult mathematical problem yet solved with the assistance of AI. Abhishek Saha of Queen Mary University of London noted that while the result is surprising, the single-line counterexample is relatively easy to verify. The finding is significant because many mathematicians had intuitively believed the conjecture to be true, leading most research efforts toward proving it rather than disproving it.

AI's role in mathematical research

While the counterexample addresses the conjecture for three variables, researchers note that a two-variable version of the problem may still hold true. The use of AI in this discovery has prompted discussions regarding the future of the field. Chris Bowman-Scargill of the University of York highlighted that while AI can identify counterexamples, human creativity remains essential for building the complex, multi-page theories often required for major mathematical proofs. Ivan Fesenko of Westlake University suggested that increasingly capable AI models could lead to fundamental changes in how mathematics is practiced, potentially reaching the level of PhD-quality work within a year.

Timeline

  1. 1939
    Ott-Heinrich Keller formally set out the Jacobian conjecture.
  2. 1998
    Stephen Smale included the conjecture on a list of 18 difficult problems for the 21st century.
  3. 19 July
    Levent Alpöge announced the disproof of the conjecture on X.

Advertisement

This article was independently rewritten by ManyPress editorial AI from reporting originally published by New Scientist.

Science