Renowned astrophysicist and educator Alex Filippenko joins Brian Greene to discuss an increasingly disturbing cosmological mismatch known as the Hubble Tension, a gap that may require a radical rewriting of the history of the universe. This program is part of the Big Ideas series, supported by the John Templeton Foundation. Participant: Alex Filippenko Moderator: Brian Greene 0:00:00 - Introduction 0:00:50 - Welcome to Alex Filippenko 0:03:58 - The Most Important Lesson of Science 0:06:47 - The Hubble Tension 0:12:04 - Measuring the Expansion Rate of the Universe 0:23:31 - How far out can we measure? 0:27:10 - Galaxies with Type 1A Supernovae and Cepheids 0:32:57 - Cosmic Distance Ladder Summary 0:37:30 - The Universe's Expansion Rate Today 0:47:20 - How can we be certain the measurements are correct? 0:51:00 - CMB and using Theoretical Models to Extrapolate the Expansion Rate 1:00:57 - Positive outcomes to this tension 1:02:14 - Filippenko's thoughts on the position of Wendy Free...