Izzie Clarke and Dr Becky Smethurst are rounding off 2023 with a biggie. Arguably the biggest of them all. This episode is ALL about the Multiverse. What is it? What does it mean? Does it even exist?   A big thank you to Andrew Pontzen from UCL and author of "Universe in a Box" for explaining the basics, Katie Mack from The Perimeter Institute for going from physicist to film reviewer, and to listener Wendy Entwistle who suggested the Supermassive team cover this topic. The Supermassive Podcast is a Boffin Media production for the Royal Astronomical Society. The producers are Izzie Clarke and Richard Hollingham.