Amateur mathematicians are using artificial intelligence chatbots to solve long-standing problems, in a move that has taken professionals by surprise. While the problems in question aren't the most advanced in the mathematical canon, the success of AI models in tackling them shows that their mathematical performance has passed a significant threshold, say researchers, and could fundamentally change the way we do mathematics. The questions being solved by AI originate from Hungarian mathematician Paul Erdős, who was famous for his ability to pose useful but difficult questions during a career that spanned over six decades. "The questions tended to be very simple, but very hard," says Thomas Bloom at the University of Manchester, UK. By his death in 1996, there were more than 1000 of these unsolved Erdős problems, spanning a wide range of mathematical disciplines, from combinatorics (the study of combinations) to number theory.

As rates of mental health conditions like depression spike, we desperately need new ways of identifying and treating people in distress. The last big breakthrough in treating depression was all the way back in the 1980s. That was when Prozac, the first SSRI antidepressant, was released. It and its subsequent copycats soon swept the globe, and hundreds of millions of people have now taken this kind of medication. But while three-quarters of people say the pills have helped them feel better, they don't work for everyone.