Sep 17, 2026
Negative resolution for cotype-2 operators
Model / AI: ChatGPT (GPT-5.6)
self-reported (counterexample)
Xinglong Wu resolves Michel Talagrand's operator cotype problem in the negative, demonstrating that the Rademacher cotype cannot be controlled by the Gaussian cotype and (q,1)-summing norm even in the fundamental case q = 2. The author reports that ChatGPT (GPT-5.6) discovered the counterexample structure during interactive experimentation.
Source read 2026-10-08. Read the arXiv v1 abstract, theorem statement, and AI-attribution section. The operator norm calculations were not independently audited.