246 - Tim Maudlin: A Masterclass on General Relativity

Tim Maudlin is Professor of Philosophy at NYU and Founder and Director of the John Bell Institute for the Foundations of Physics. This is Tim’s seventh appearance on the show. He last appeared on episode 237 for a masterclass on Albert Einstein’s theory of special relativity, explaining it from the ground up and elucidating some common misconceptions. In this episode Tim returns for a discussion of another of Einstein’s major impacts on physics: his theory of general relativity. More particularly, Tim and Robinson discuss black holes, time, paradoxes of distance, Penrose diagrams, figures like Leonard Susskind and Richard Feynman, the curvature of space, and more. If you’re interested in the foundations of physics, then please check out the JBI, which is devoted to providing a home for research and education in this important area. Any donations are immensely helpful at this early stage in the institute’s life. Tim’s Website: www.tim-maudlin.site The John Bell Institute: https://www.johnbellinstitute.org 00:00:42 An Extended Prelude 00:05:08 Naming Names 00:10:02 The Difference Between Quantum Mechanics and General Relativity 00:13:46 Einstein on General Relativity and Metric 00:27:21 More on Coordinates 00:40:26 A Novel Coordinate System 00:46:25 What Is Special Relativity? 00:50:30 The Conflict Between Quantum Theory and Relativity 01:02:00 Doing Physics with Geometry 01:12:38 Geometry and Special Relativity 01:30:20 More on Geometry and Relativity 01:36:19 Lorentz Frames 01:46:56 Simultaneity 02:02:03 John Bell and Special Relativity 02:11:00 Paradoxes of Distance 02:22:12 A Penrose Diagram 02:27:47 Introducing General Relativity 02:32:23 The Most Important Experiment About Gravity  02:45:52 Changing the Geometry of Spacetime 02:55:28 Curvature of Space 03:02:03 Be Careful with Diagrams in Science  03:05:45 The Basic Idea of General Relativity 03:10:23 The Equivalence Principle 03:19:40 Clocks and Gravity 03:28:09 Richard Feynman on General Relativity 03:37:00 The Cosmological Constant 03:41:56 What Are Black Holes? 03:50:45 What Steven Weinberg Got Wrong About General Relativity  04:01:01 Black Holes and the Centrifugal Force Paradox 04:06:32 Curved Black Holes and Gödel Spacetime 04:19:34 The John Bell Institute Robinson’s Website: http://robinsonerhardt.com Robinson Erhardt researches symbolic logic and the foundations of mathematics at Stanford University.