Does infinity exist?

“Is anything in the Universe truly infinite, or is infinity something that only exists in mathematics?” This question came from father and son duo from Edinburgh in Scotland, Tom and Sorely Watson. First, we investigate the concept of infinity in mathematics with a story of mathematics, music and murder from Steven Strogatz from the Cornell University. Did you know that there are some infinities that are bigger than others? We discuss the mind-bending nature of infinity with mathematician Eugenia Cheng, author of Beyond Infinity. Next we turn to physics to see if we can find something in the Universe that is truly infinite. Theoretical physicist Sean Carroll from Caltech University discusses the infinitely small inside subatomic particles. Plus cosmologist Andrew Pontzen from University College London travels into the heart of a black hole to see if we can find a something that is infinitely dense. But if we’re looking for something that is infinite, how about the Universe itself? We find out how physicists measure the shape of the Universe, with the help of an orange and a game of Asteroids. However, if the Universe is not infinite, and it has an edge, what is on the other side? Presenters: Hannah Fry, Adam Rutherford Producer: Michelle Martin (Photo: The Infinity symbol in an exploding cloud of data. Credit: Wigglestick/Getty Images)