Between 1905 and 1910 the idea of the random walk, now a major topic in applied maths, was invented simultaneously and independently by multiple people in multiple countries for completely different purposes – in the UK, the story starts with Ronald Ross and the problem of mosquito control, but elsewhere, the theory was being developed in domains from physics to finance to winning a theological argument (really!).

Jordan tells some part of this story and also gesture at ways that random walks (or Markov processes, named after the theological arguer) underlie current approaches to artificial intelligence; he touches on some of his own work with DeepMind and speculates about the capabilities of those systems now and in the future.

Jordan Ellenberg is a Professor of Mathematics at the University of Wisconsin-Madison.