Claude Solves Nine-Loop Scattering Amplitude, Breaking Physics Record

Anthropic's Claude computed a nine-loop scattering amplitude in the planar N=4 super-Yang-Mills model, surpassing the previous eight-loop record held by SLAC physicist Lance Dixon and collaborators. Given a single prompt, Claude ran largely unsupervised for days inside the Claude Science environment, at a total cost of a few thousand dollars. Dixon independently verified the result using his group's existing verification tools. The problem involves calculating six-particle scattering amplitudes, where each additional loop exponentially multiplies computational complexity; most such calculations stop at two or three loops. The N=4 super-Yang-Mills model is a simplified setting physicists use as a testing ground. The challenge was originally posed by a physicist and science writer known as @4gravitons, asking whether AI could advance past eight loops within an academic compute budget. Dixon said Claude "understands our 2019 and 2023 papers better than any human, aside from my co-authors." The computation ran with only periodic continuation prompts and no mid-run scientific corrections. Model inference costs dominated the overall expense, while the numerical calculation itself used modest conventional computing resources.