Welcome to the first ever edition of Voices of Mathematics, a podcast from the Mathematics Faculty at the University of Cambridge. From number theory and geometry to cosmology and quantum physics, join us to explore topics across pure and applied mathematics, mathematical statistics and theoretical physics.   In this episode we talk to David Tong, Professor of Theoretical Physics at the Department of Applied Mathematics and Theoretical Physics. 2025 marks an important milestone in the history of physics: the 100th birthday of quantum mechanics. We ask David about the ongoing impact of the discovery a century ago, and explore how this links to his own research area of quantum field theory.  And, as he publishes a series of textbooks based on his celebrated lecture notes, David shares some of the exciting connections between very different areas of physics.   The podcast is hosted by Marianne Freiberger and Rachel Thomas, Editors of Plus, from the communications and outreach team at the Mathematics Faculty.   To find out more about topics mentioned in this podcast see: David Tong's series of text books A brief introduction to quantum mechanics on Plus A brief history of quantum field theory on Plus Sean Carroll's Mindscape podcast featuring David Tong   Discover more about the University of Cambridge Faculty of Mathematics at maths.cam.ac.uk.