OpenAI announced that one of its general-purpose reasoning models has autonomously solved the planar unit distance problem, a famous open question in discrete geometry first posed by mathematician Paul Erdős in 1946. The AI discovered an entirely new family of constructions that outperforms the square-grid-based solutions that mathematicians had believed were optimal for nearly 80 years. This represents the first time an AI has independently solved a prominent open problem in pure mathematics, demonstrating advanced reasoning capabilities that could accelerate research across multiple scientific fields.