Sean Carroll's Mindscape 211318

Einstein's general theory of relativity, plus some reasonable assumptions about the universe and what it's made of, has a remarkable implication: that as we trace cosmic evolution into the far past, we ultimately hit a singularity of infinite density and curvature, the Big Bang. Did that really happen? Einstein's theory is classical, after all, and the world is quantum. And whose to say what assumptions are reasonable? Niayesh Afshordi and Phil Halper have written a new book, Battle of the Big Bang: The New Tales of Our Cosmic Origins, that surveys all of the mind-bending possibilities. Blog post with transcript: https://www.preposterousuniverse.com/podcast/2025/05/26/316-niayesh-afshordi-and-phil-halper-on-the-big-bang-and-before/ Mindscape on Patreon. Niayesh Afshordi received a Ph.D. in astrophysics from Princeton University. He is currently a professor of physics and astronomy at the University of Waterloo, and associate faculty in the cosmology and gravitation group at the Perimeter Institute for Theoretical Physics. Web site Perimeter web page Waterloo web page Google scholar publications Phil Halper is a science communicator and a fellow of the Royal Astronomical Society. His astronomy images have been featured in major media outlets including The Washington Post, the BBC, and The Guardian, and he has published several papers in peer-reviewed journals. YouTube channel (Skydivephil) See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Every time you see an apple spontaneously break away from a tree, it falls downward. You therefore claim that there is a law of physics: apples fall downward from trees. But how can you really know? After all, tomorrow you might see an apple that falls upward. How is science possible at all? Philosophers, as you might expect, have thought hard about this. Branden Fitelson explains how a better understanding of probability can help us decide when new evidence is actually confirming our beliefs. Blog post with transcript: https://www.preposterousuniverse.com/podcast/2025/05/19/315-branden-fitelson-on-the-logic-and-use-of-probability/ Mindscape on Patreon. Branden Fitelson received a Ph.D. in philosophy from the University of Wisconsin-Madison. He is currently Distinguished Professor of Philosophy at Northeastern University. He is a co-founder of the Formal Epistemology Workshop, and winner of the 2020 Wolfram Innovator Award. Web site Northeastern web page PhilPapers profile Google Scholar publications Wikipedia See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

There are living creatures dwelling deep below the surface of the Earth, as deep as we are able to drill. These hearty microorganisms are related to more familiar life forms on land and under water, but the operate and survive in ways that are quite different from what we're familiar with. They live off of nutrients that have penetrated from the surface, or sometimes off of pure electrons. Karen Lloyd is a scientist who has traveled around the world studying these organisms, as she explains in her new book Intraterrestrials: Discovering the Strangest Life on Earth. Blog post with transcript: https://www.preposterousuniverse.com/podcast/2025/05/12/314-karen-lloyd-on-the-deep-underground-biosphere/ Mindscape on Patreon. Karen Lloyd received a Ph.D. in marine sciences from the University of North Carolina. She is currently the Wrigley Chair in Environmental Studies and Professor of Earth Sciences at the University of Southern California. Among her awards are a Sloan Fellowship, a Simons Early Career Investigator, and a NASA Early Career Fellowship. Lab web site USC web page Google Scholar publications Bluesky See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Medical science is advancing at an astonishing rate. Today we talk with leading expert Eric Topol about two aspects of this story. First, the use of artificial intelligence in medicine, especially in diagnostics. This is an area that is a perfect match between an important question and the capabilities of machine learning, to the point where AI can out-perform human doctors. And second, our understanding of aging and what to do about it. Eric even gives some actionable advice on how to live more healthily into our golden years. Blog post with transcript: https://www.preposterousuniverse.com/podcast/2025/05/05/episode-313-eric-topol-on-the-changing-face-of-medicine-and-aging/ Mindscape on Patreon. Eric Topol received and M.D. from the University of Rochester. He is currently the Gary and Mary West Chair of Innovative Medicine in the Department of Translational Medicine at Scripps Research. He is also the Founder, Scripps Research Translational Institute, and Senior Consultant, Scripps Clinic, Division of Cardiovascular Diseases. Among his awards are the Hutchinson Medal from the University of Rochester and hip in the National Academy of Sciences. His books include Deep Medicine: How Artificial Intelligence Can Make Healthcare Human Again, and Super Agers: An Evidence-Based Approach to Longevity. Web site Scripps web page Google Scholar publications Wikipedia Substack Bluesky See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Welcome to the May 2025 Ask Me Anything episode of Mindscape! These monthly excursions are funded by Patreon ers (who are also the ones asking the questions). We take questions asked by Patreons, whittle them down to a more manageable number -- based primarily on whether I have anything interesting to say about them, not whether the questions themselves are good -- and sometimes group them together if they are about a similar topic. Enjoy! Blog post with AMA questions and transcript: https://www.preposterousuniverse.com/podcast/2025/04/28/ama-may-2025/ Mindscape on Patreon. See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

The germ theory of disease is a crowning achievement of science, up there with modern physics, continental drift, and evolution via natural selection. (Even if there will always be cranky skeptics.) But the road to widespread acceptance isn't always an easy one. Why did it take so long between Anton van Leeuwenhoek seeing "animalcules" in a microscope (1670s) to Louis Pasteur's work on pasteurization and vaccination (1860's)? Thomas Levenson is the author of a new book exploring this fascinating history: So Very Small: How Humans Discovered the Microcosmos, Defeated Germs--and May Still Lose the War Against Infectious Disease. Blog post with transcript: https://www.preposterousuniverse.com/podcast/2025/04/21/episode-312-thomas-levenson-on-the-mutual-history-of-humans-and-germs/ Mindscape on Patreon. Thomas Levenson received a B.A. in East Asian Studies from Harvard University. He is currently Professor of Science Writing and director of the graduate program in science writing at the Massachusetts Institute of Technology. He is the author of numerous books and has written and produced a number of science documentaries for television. Web site MIT web page Wikipedia Amazon author page Bluesky See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Questions about consciousness range from the precise and empirical -- what neurons fire when I have some particular experience -- to the deeply profound -- does consciousness emerge from matter, or does matter emerge from consciousness? While it might be straightforward to think that consciousness arises from the collective behavior of atoms in the brain, Annaka Harris and others argue that consciousness could be the fundamental stuff from which matter arises. She talks with a variety of experts in her new audio series, Lights On: How Understanding Consciousness Helps Us Understand the Universe. Blog post with show notes and transcript: https://www.preposterousuniverse.com/podcast/2025/04/14/311-annaka-harris-on-whether-consciousness-is-fundamental/ Mindscape on Patreon. Annaka Harris received a BFA from New York University. She is the author of Consciousness: A Brief Guide to the Fundamental Mystery of the Mind. She is a co-founder of Project Reason. Web site Wikipedia Amazon author page See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Welcome to the April 2025 Ask Me Anything episode of Mindscape! These monthly excursions are funded by Patreon ers (who are also the ones asking the questions). We take questions asked by Patreons, whittle them down to a more manageable number -- based primarily on whether I have anything interesting to say about them, not whether the questions themselves are good -- and sometimes group them together if they are about a similar topic. Enjoy! Blog post with questions and transcript: https://www.preposterousuniverse.com/podcast/2025/04/07/ama-april-2025/ Mindscape on Patreon. A couple of links relevant to the intro: Tariff formula (Snopes) Tufts student nabbed by ICE (plus video) See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Cosmologists were, let us be honest, pretty stunned in 1998 when observations revealed that the universe is accelerating. There was an obvious plausible explanation, the cosmological constant proposed by Einstein, which is equivalent to a constant vacuum energy pervading space. But the cosmological constant was known to be enormously smaller than its "natural" value, and it seems fine-tuned for it to be so small but not yet zero. Once burned, twice shy, and since then we have been looking for evidence that the dark energy might not be strictly constant, even though that's even more fine-tuned. We talk to cosmologist Marc Kamionkowski about recent evidence that dark energy might be changing with time, and what this might have to do with the Hubble tension and other cosmic anomalies. Blog post with transcript: https://www.preposterousuniverse.com/podcast/2025/03/31/310-marc-kamionkowski-on-dark-energy-and-cosmic-anomalies/ Mindscape on Patreon. Marc Kamionkowski received his Ph.D. in physics from the University of Chicago. He is currently the William R. Kenan Jr. Professor in the Department of Physics and Astronomy at Johns Hopkins University. Among his prizes are the Gruber Cosmology Prize, the Dannie Heineman Prize for Astrophysics, hip in the National Academy of Science, and a Guggenheim Fellowship. Johns Hopkins web page Google Scholar publications Wikipedia Kamionkowski and Riess, "The Hubble Tension and Early Dark Energy" Dark Energy Spectroscopic Instrument paper and followup Dark Energy Survey paper See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Consciousness is easier to possess than to define. One thing we can do is to look into the brain and see what lights up when conscious awareness is taking place. A complete understanding of this would be known as the "neural correlates of consciousness." Once we have that, we could hopefully make progress on developing a theoretical picture of what consciousness is and why it happens. Today's guest, Christof Koch, is a leader in the search for neural correlates and an advocate of a particular approach to consciousness, Integrated Information Theory. Blog post with transcript: https://www.preposterousuniverse.com/podcast/2025/03/24/309-christof-koch-on-consciousness-and-integrated-information/ Mindscape on Patreon. Christof Koch was awarded a Ph.D. from the Max Planck Institute for Biological Cybernetics. He is currently a Meritorious Investigator at the Allen Institute for Brain Science, where he was formerly president and chief scientist, and Chief Scientist at the Tiny Blue Dot Foundation. He is the author of several books, most recently Then I Am Myself the World - What Consciousness Is and How to Expand It. Web site Allen Center web page Google Scholar publications Amazon author page Wikipedia See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

We often study cognition in other species, in part to learn about modes of thinking that are different from our own. Today's guest, psychologist/philosopher Alison Gopnik, argues that we needn't look that far: human children aren't simply undeveloped adults, they have a way of thinking that is importantly distinct from that of grownups. Children are explorers with ever-expanding neural connections; adults are exploiters who (they think) know how the world works. These studies have important implications for the training and use of artificial intelligence. Blog post with transcript: https://www.preposterousuniverse.com/podcast/2025/03/17/308-alison-gopnik-on-children-ai-and-modes-of-thinking/ Mindscape on Patreon. Alison Gopnik received her D.Phil in experimental psychology from Oxford University. She is currently a professor of psychology and professor of philosophy at the University of California, Berkeley. Among her awards are the Association for Psychological Science Lifetime Achievement Award, the Rumelhart Prize for Theoretical Foundations of Cognitive Science, and a Guggenheim Fellowship. She is a past President of the Association for Psychological Science. She is the author of The Scientist in the Crib, The Philosophical Baby, and The Gardener and the Carpenter, among other works. Web site Lab web site Berkeley web page Google Scholar publications Amazon author page Wikipedia See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Welcome to the March 2025 Ask Me Anything episode of Mindscape! These monthly excursions are funded by Patreon ers (who are also the ones asking the questions). We take questions asked by Patreons, whittle them down to a more manageable number -- based primarily on whether I have anything interesting to say about them, not whether the questions themselves are good -- and sometimes group them together if they are about a similar topic. Enjoy! Link to the 2012 Moving Naturalism Forward workshop, mentioned in the episode. Blog post with questions and full transcript: https://www.preposterousuniverse.com/podcast/2025/03/10/ama-march-2025/ Mindscape on Patreon. See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

A lot of science goes into crafting the perfect cocktail. Balancing sweet and bitter notes, providing the right amount of aeration and dilution, getting it to just the right temperature and keeping it that way. And even if you have no interest in cocktails as such, the general principles extend to other activities in art and in life. I talk to scientist-turned-mixologist Kevin Peterson about how to think about the simple magic of a perfect drink. Blog post with transcript: https://www.preposterousuniverse.com/podcast/2025/03/03/307-kevin-peterson-on-the-theory-of-cocktails/ Mindscape on Patreon. Kevin Peterson received a Ph.D. in Mechanical Engineering from the University of Michigan. He is currently co-owner of both Castalia (an experimental craft cocktail bar) and Sfumato Fragrances in Detroit, Michigan. He is the author of Cocktail Theory: A Sensory Approach to Transcendent Cocktails. Mindscape Petrichor Negroni (from the episode) 1 part gin distilled from vetiver (alternative: herbaceous gin such as Moletto) 1 part St. George Bruto Americano 1 part Antica Formula vermouth Stir over an ice cube, express with orange peel (not shown). See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

It is commonplace to refer to the Earth's oceans as vast and largely unexplored. But we do understand some aspects, and improving that understanding is crucial to ensuring the continued viability and success of life on this planet. The oceans are a paradigmatic complex system: there are many components, distinct but mutually interacting, that add up to a nuanced whole. We talk with ocean physicist Helen Czerski about what the ocean is and how it's changing. Blog post with transcript: https://www.preposterousuniverse.com/podcast/2025/02/24/306-helen-czerski-on-our-energetic-oceans/ Mindscape on Patreon. Helen Czerski received her Ph.D. in physics from the University of Cambridge. She is currently an Associate Professor at the Department of Mechanical Engineering at University College London. She is the author of several books, most recently The Blue Machine: How the Ocean Works. She is a frequent television presenter for the BBC and elsewhere. Web site UCL web page Google Scholar publications Wikipedia Amazon author page Bluesky See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Political outcomes would be relatively simple to predict and understand if only people were well-informed, entirely rational, and perfectly self-interested. Alas, real human beings are messy, emotional, imperfect creatures, so a successful theory of politics has to for these features. One phenomenon that has grown in recent years is an alignment of cultural differences with political ones, so that polarization becomes more entrenched and even violent. I talk with political scientist Lilliana Mason about how this has come to , and how democracy can deal with it. Blog post with transcript: https://www.preposterousuniverse.com/podcast/2025/02/17/305-lilliana-mason-on-polarization-and-political-psychology/ Mindscape on Patreon. Lilliana Hall Mason received her Ph.D. in political psychology from Stony Brook University. She is currently an SNF Agora Institute Associate Professor of Political Science at Johns Hopkins University. She is the author of Uncivil Agreement: How Politics Became Our Identity and co-author (with Nathan Kalmoe) of Radical American Partisanship: Mapping Violent Hostility, Its Causes, and the Consequences for Democracy. Web Site Hopkins web page Google Scholar publications Bluesky See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

The Trump istration, led by Elon Musk and his Department of Government Efficiency, has proposed sweeping cuts to spending on science research here in the US, in particular at the National Institutes of Health and the National Science Foundation. I explain a little about what is being cut and why these funds are important to scientific progress. I try, for what it's worth, to provide these explanations in a way that would be informative to those who generally favor cutting government waste in dramatic fashion. Blog post with transcript: https://www.preposterousuniverse.com/podcast/2025/02/12/bonus-cuts-to-science-funding-and-why-they-matter/ Mindscape on Patreon. Indirect costs primer Cuts to NIH indirect costs Appropriated funds are mandated by statute Proposed NSF cuts Elon Musk doesn't understand indirect costs Bribing foreign officials Deleting NSA web pages Executive Orders are not laws History of impoundments See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

It is a feature of many human activities - sports, cooking, music, interpersonal relations - that being able to do them well doesn't necessarily mean you can accurately describe how to do them well. Science is no different. Many successful scientists are not very good at explaining what goes into successful scientific practice. To understand that, it's necessary to study science in a scientific fashion. What kinds of scientists, in what kinds of collaborations, using what kinds of techniques, do well? I talk with James Evans, an expert on collective intelligence and the construction of knowledge, about how science really works. Blog post with transcript: https://www.preposterousuniverse.com/podcast/2025/02/10/304-james-evans-on-innovation-consolidation-and-the-science-of-science/ Mindscape on Patreon. James Evans received his Ph.D. in Sociology from Stanford University. He is currently the Max Palevsky Professor of History and Civilizations, Director of Knowledge Lab, and Faculty Director of Computational Social Science at the University of Chicago; External Professor at the Santa Fe Institute; External Faculty at the Complexity Science Hub, Vienna; and Visiting Faculty Researcher at Google. Knowledge Lab web site University of Chicago web page Google scholar publications See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Welcome to the February 2025 Ask Me Anything episode of Mindscape! These monthly excursions are funded by Patreon ers (who are also the ones asking the questions). We take questions asked by Patreons, whittle them down to a more manageable number -- based primarily on whether I have anything interesting to say about them, not whether the questions themselves are good -- and sometimes group them together if they are about a similar topic. Enjoy! Blog post with questions and transcript: https://www.preposterousuniverse.com/podcast/2025/02/03/ama-february-2025/ Mindscape on Patreon. See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

A typical human lifespan is approximately three billion heartbeats in duration. Lasting that long requires not only intrinsic stability, but an impressive capacity for self-repair. Nevertheless, things do occasionally break down, and cancer is one of the most dramatic examples of such breakdown. Given that the body is generally so good at protecting itself, can we harness our internal security patrol - the immune system - to fight cancer? This is the hope of Nobel Laureate James Allison, who works on studying the structure and behavior of immune cells, and ways to coax them into fighting cancer. This approach offers hope of a way to combat cancer effectively, lastingly, and in a relatively gentle way. Mindscape on Patreon. Blog post with transcript: https://www.preposterousuniverse.com/podcast/2025/01/27/303-james-p-allison-on-fighting-cancer-with-the-immune-system/ James P. Allison received his Ph.D. in biology from the University of Texas at Austin. He is currently Regental Professor and Chair of the Department of Immunology, the Olga Keith Wiess Distinguished University Chair for Cancer Research, Director of the Parker Institute for Cancer Research, and Director of the James P. Allison Institute at MD Anderson Cancer Center. He is the subject of the documentary film Jim Allison: Breakthrough. Among his numerous awards are the Breakthrough Prize in Life Sciences and the Nobel Prize in Physiology or Medicine. Web page Nobel Prize citation Google Scholar publications Wikipedia See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Randomness plays an important role in the evolution of life (as my evil twin will tell you). But random doesn't mean arbitrary. Biological organisms are physical objects, after all, and subject to the same laws of physics as non-biological matter is. Those laws place constraints on how organisms can fulfill their basic functions of metabolism, reproduction, motility, and so on. Easy to say, but how can we turn this into quantitative understanding of actual organisms? Today I talk with physical biologist Chris Kempes about how physics can help us understand the size of organisms, their metabolisms, and features of major transitions in evolution. Mindscape on Patreon. Blog post with transcript: https://www.preposterousuniverse.com/podcast/2025/01/20/302-chris-kempes-on-the-biophysics-of-evolution/ Chris Kempes received his Ph.D. in physical biology from the Massachusetts Institute of Technology. He is currently Professor and a member of the Science Steering Committee at the Santa Fe Institute. His research involves the origin of life and the constraints placed by physics on biological function and evolution. Web site Santa Fe Institute web page Google Scholar publications Origins of Life online course See at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.