Quantum field theory may be the most successful scientific theory of all time, predicting  experimental results with stunning accuracy and advancing the study of higher dimensional mathematics. Yet, there’s also reason to believe that it is missing something. Steven Strogatz speaks with David Tong, a theoretical physicist at the University of Cambridge, to explore the open questions of this enigmatic theory.

“The Joy of Why” is a podcast from Quanta Magazine, an editorially independent publication supported by the Simons Foundation. Funding decisions by the Simons Foundation have no influence on the selection of topics, guests, or other editorial decisions in this podcast or in Quanta Magazine. “The Joy of Why” is produced by Susan Valot and Polly Stryker. Our editors are John Rennie and Thomas Lin, with support by Matt Carlstrom, Annie Melchor and Leila Sloman. Our theme music was composed by Richie Johnson. Our logo is by Jackie King, and artwork for the episodes is by Michael Driver and Samuel Velasco. Our host is Steven Strogatz. If you have any questions or comments for us, please email us at quanta@simonsfoundation.org.