Expanded Horizons

In this new series, mathematician Dr. Hannah Fry explores the mystery of math. It underpins so much of our modern world that its hard to imagine life without its technological advances, but where exactly does math come from? Is it invented like a language or is it something discovered, part of the fabric of the universe? As we increasingly come to rely on math, this question becomes more important to answer.

In this episode, Hannah travels down the fastest zip wire in the world to learn more about Newton's ideas on gravity. His discoveries revealed the movement of the planets was regular and predictable. James Clerk Maxwell unified the ideas of electricity and magnetism, and explained what light was. As if that wasn't enough, he also predicted the existence of radio waves. His tools of the trade were nothing more than pure mathematics. All strong evidence for math being discovered.

But in the 19th century, math is turned on its head when new types of geometry are invented. No longer is the kind of geometry we learned in school the final say on the subject. If math is more like a game, albeit a complicated one, where we can change the rules, surely this points to math being something we invent - a product of the human mind. To try and answer this question, Hannah travels to Halle in Germany on the trail of perhaps one of the greatest mathematicians of the 20th century, Georg Cantor. He showed that infinity, far from being infinitely big, actually comes in different sizes, some bigger than others. This increasingly weird world is feeling more and more like something we've invented. But if that's the case, why is math so uncannily good at predicting the world around us? Invented or discovered, this question just got a lot harder to answer.