quantamagazine.orgOn May 20, 2026, OpenAI made an announcement that shook the mathematical world. An internal AI model - one not available to the public - had come up with a counterexample to the "unit distance" problem, a conjecture made in 1946 by Paul Erdős, the prolific, itinerant Hungarian mathematician. Erdős posed thousands of questions, but this one was special: It was both simple to explain and…