GPT-5 generates the "most impressive LLM output" yet, says OpenAI researcher

OpenAI researcher Sebastien Bubeck says GPT-5's math skills saved him a month of work. In a post on X, Bubeck reports that GPT-5 tackled a highly complex mathematical task for him. The model designed the solution path, ran a simulation to check a formula, and then wrote a complete proof, effectively a seamless calculation. While this process would have previously taken him around a month, GPT-5 finished it in just an afternoon. Bubeck calls it the "most impressive LLM output" he has seen to date.

Generative AI is becoming increasingly apparent in high-level mathematics—and not just because of gold medals in Math Olympiads. Mathematician Terence Tao recently noted that AI saved him several hours of work, though he used the tool to verify his theoretical assumptions rather than relying on it autonomously. An OpenAI report backs this up, showing how GPT-5 can save significant research time across various scientific fields.