A counterexample to Pixton completeness in Chow

What OpenAI claims

Constructs a tautological relation on a moduli space of stable pointed curves that vanishes in rational Chow, hence in rational cohomology, but lies outside Pixton's original relation span. This disproves the Chow and rational-cohomological forms of his original completeness conjecture.

Paper

1. A high-arity counterexample to Pixton completeness in Chow

   24 September 2026 · Preprint, not peer reviewed · PDF

   We disprove the Chow and rational-cohomological forms of Pixton's completeness conjecture for his original relation system. We construct a formal tautological class outside the original Pixton relation span whose image is zero in the Chow ring and in rational cohomology. The example has genus 10⁶⁰ and 3(10⁶⁰ choose 3) markings.

Status

Preprint. The paper has not been independently reviewed. Treat the result as OpenAI's claim until other mathematicians have checked it. If a video exists, it illustrates the statement; it is not the proof.