How fast is the universe expanding? Two prominent approaches are finding different answers, propelling cosmology toward a crisis. Wendy Freedman, a renowned astronomer who has spent decades seeking the expansion rate, joins Brian Greene to discuss the latest thinking on this so-called Hubble Tension. This program is part of the Big Ideas series, supported by the John Templeton Foundation. Participant: Wendy Freedman Moderator: Brian Greene 00:00 - Introduction 02:40 - Participant introductions 04:40 - The History of Cosmic Expansion 9:40 - Henrietta Swan Leavitt's Contributions to Cosmology 11:45 - Cepheid Variable 15:04 - How did Hubble calculate Expansion Rate? 21:05 - Modern Measurements of Expansion Rate 26:09 - Determining Expansion rate using Microwave Background Radiation 28:30 - Can We Resolve Hubble Tension? 31:46 - James Webb Space Telescope's Impact on Expansion Rate 34:02 - The Future of Cosmology 35:19 - Credits WSF Landing Page: worldsciencefestival.com...