Sean Carroll's Mindscape: Science, Society, Philosophy, Culture, Arts, and Ideas

The challenge to a theoretical physicist pushing beyond our best current theories is that there are too many ways to go. What parts of the existing paradigm do you keep, which do you discard, and why make those choices? Among today’s theorists, Lee Smolin is unusually reflective about what principles should guide us in the construction of new theories. And he is happy to suggest radical revisions to well-established ideas, in areas from the nature of time to the workings of quantum mechanics. We talk about time, the universe, the role of philosophy, a new picture of spacetime, and the future of physics.

Support Mindscape on Patreon.

Lee Smolin received his Ph.D. in physics from Harvard University. He is currently on the faculty of the Perimeter Institute in Waterloo, Canada, where he was a founding member. Among his awards are the Majorana Prize, the Klopsteg Memorial Award, and the Buchalter Cosmology Prize. He is the author of several books, most recently Einstein’s Unfinished Revolution: The Search for What Lies Beyond the Quantum.

• Web site
• Perimeter Institute page
• Google Scholar publications
• Amazon author page
• Wikipedia

See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

The 200th episode of Mindscape! Thanks to everyone for sticking around for this long. To celebrate, a solo episode discussing a set of issues naturally arising at the intersection of philosophy and physics: how to think about probabilities and expectations in a multiverse. Here I am more about explaining the issues than offering correct answers, although I try to do a bit of that as well.

Support Mindscape on Patreon.

References:

• Guth, “Inflation and Eternal Inflation“
• Weinberg, “Living In the Multiverse“
• Susskind, “The Anthropic Landscape of String Theory“
• Carroll, Johnson, and Randall, “Dynamical Compactification from De Sitter Space“
• Sebens and Carroll, “Self-Locating Uncertainty and the Origin of Probability in Everettian Quantum Mechanics“
• Wald, “Asymptotic behavior of homogeneous cosmological models in the presence of a positive cosmological constant“
• Gibbons and Hawking, “Cosmological Event Horizons, Thermodynamics, and Particle Creation“
• Carroll and Chatwin-Davies, “Cosmic Equilibration: A Holographic No-Hair Theorem from the Generalized Second Law“
• Dyson, Kleban, and Susskind, “Disturbing Implications of a Cosmological Constant“
• Albrecht and Sorbo, “Can the Universe Afford Inflation?“
• Boddy, Carroll, and Pollack, “De Sitter Space Without Dynamical Quantum Fluctuations“
• Carroll, “Why Boltzmann Brains Are Bad“
• Aguirre, Carroll, and Johnson, “Out of Equilibrium: Understanding Cosmological Evolution to Lower-Entropy States“
• Carroll, “Beyond Falsifiabiliy: Normal Science in a Multiverse“
• Carter and McCrea, “The Anthropic Principle and its Implications for Biological Evolution“
• Leslie, “Doomsday Revisited“
• Gott, “Implications of the Copernican Principle for Our Future Prospects“
• Bostrom, Anthropic Bias
• Vilenkin, “The Principle of Mediocrity“
• Olum, “Conflict Between Anthropic Reasoning and Observation“
• Elga, “Self-Locating Belief and the Sleeping Beauty Problem“
• Lewis, “Sleeping Beauty: Reply to Elga“
• Hartle and Srednicki, “Are We Typical?“
• Hartle and Srednicki, “Science in a Very Large Universe“
• Neal, “Puzzles of Anthropic Reasoning Resolved Using Fully Non-Indexical Conditioning“

See Privacy Policy at https://art19.com/privacy and California Privacy Notice ...

When it comes to social change, two questions immediately present themselves: What kind of change do we want to see happen? And, how do we bring it about? These questions are distinct but related; there's not much point in spending all of our time wanting change that won't possibly happen, or working for change that wouldn't actually be good. Addressing such issues lies at the intersection of philosophy, political science, and social dynamics. Sahar Heydari Fard looks at all of these issues through the lens of complex systems theory, to better understand how the world works and how it might be improved.

Blog post with transcript: https://www.preposterousuniverse.com/podcast/2024/03/18/269-sahar-heydari-fard-on-complexity-justice-and-social-dynamics/

Support Mindscape on Patreon.

Sahar Heydari Fard received a Masters in applied economics and a Ph.D. in philosophy from the University of Cincinnati. She is currently an assistant professor in philosophy at the Ohio State University. Her research lies at the intersection of social and behavioral sciences, social and political philosophy, and ethics, using tools from complex systems theory.

• Web site
• Ohio State web page
• PhilPeople profile
• Google Scholar publications

See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

In the 1860s, James Clerk Maxwell argued that light was a wave of electric and magnetic fields. But it took over four decades for physicists to put together the theory of special relativity, which correctly describes the symmetries underlying Maxwell's theory. The delay came in part from the difficulty in accepting that light was a wave, but not a wave in any underlying "aether." Today our most basic view of fundamental physics is found in quantum field theory, which posits that everything around us is a quantum version of a relativistic wave. I talk with physicist Matt Strassler about how we go from these interesting-but-intimidating concepts to the everyday world of tables, chairs, and ourselves.

Blog post with transcript: https://www.preposterousuniverse.com/podcast/2024/03/04/267-matt-strassler-on-relativity-fields-and-the-language-of-reality/

Support Mindscape on Patreon.

Matt Strassler received his Ph.D. in physics from Stanford University. He is currently a writer and a visiting researcher in physics at Harvard University. His research has ranged over a number of topics in theoretical high-energy physics, from the phenomenology of dark matter and the Higgs boson to dualities in gauge theory and string theory. He blogs at Of Particular Significance, and his new book is Waves in an Impossible Sea: How Everyday Life Emerges from the Cosmic Ocean.

• Web site
• Google Scholar publications

See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Mathematics is often thought of as the pinnacle of crisp precision: the square of the hypotenuse of a right triangle isn’t “roughly” the sum of the squares of the other two sides, it’s exactly that. But we live in a world of messy imprecision, and increasingly we need sophisticated techniques to quantify and deal with approximate statistical relations rather than perfect ones. Modern mathematicians have noticed, and are taking up the challenge. Tai-Danae Bradley is a mathematician who employs very high-level ideas — category theory, topology, quantum probability theory — to analyze real-world phenomena like the structure of natural-language speech. We explore a number of cool ideas and what kinds of places they are leading us to.

Support Mindscape on Patreon.

Tai-Danae Bradley received her Ph.D. in mathematics from the CUNY Graduate Center. She is currently a research mathematician at Alphabet, visiting research professor of mathematics at The Master’s University, and executive director of the Math3ma Institute. She hosts an explanatory mathematics blog, Math3ma. She is the co-author of the graduate-level textbook Topology: A Categorical Approach.

• Web site
• Google Scholar publications
• Twitter
• Video introduction to “At the Interface of Algebra and Statistics” Ph.D. thesis

See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.