The problem
By Faltings' theorem, a curve of genus 2 over has only finitely many rational points, but how many it can have is not known. Since 2008 the record has been a curve with 642 rational points found by Elkies and Stoll. Epoch AI's FrontierMath Open Problems asked for a curve with more.
What AI did
During Epoch AI's pre-release evaluation of OpenAI's GPT-6 Astra, the model found a genus-2 curve with 648 rational points. Epoch AI's problem page gives the curve's equation. Epoch does not give the date, so we list only the year.
How it was checked
The curve passed Epoch AI's verifier. Anyone can check a claimed list of rational points on an explicit curve directly.
Limitations
This is a new record, not a resolution of the underlying question: whether the number of rational points on a genus-2 curve is bounded uniformly (the question behind the work of Caporaso, Harris and Mazur) remains open. Problem description paraphrased from Epoch AI (CC BY 4.0).
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