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

Welcome to the October 2026 Ask Me Anything episode of Mindscape! These monthly excursions are funded by Patreon supporters (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 t...

One reason it's been so hard to directly detect the dark matter is that we're not sure what it is. But for a long time, a leading candidate has been "Weakly Interacting Massive Particles" (WIMPs), so an impressive amount of experimental effort has been put into trying to detect them. Recently, a single provocative event appeared in the LUX-ZEPLIN (LZ) dark matter experiment. Daniel Akerib, a physi...

The worry about debates over free will is that they degenerate into semantics -- what do you mean by "free will," really? But there are important substantive issues that shouldn't be ignored. Do people deserve blame for doing wrong things? Can we make choices that create meaning for our lives? Philosopher Gregg Caruso denies the reality of free will, but is in favor of making good choices, as he d...

In all sorts of ways, the modern world makes it difficult to nurture our individual humanity and connect with the humanity of others. The disciplines that try to do so are, naturally enough, the humanities. Poet Elizabeth Alexander's new book, Signals Across Vast Distances , grapples with the question of how literature and other humanistic studies can help us build empathy and become better people...

Welcome to the September 2026 Ask Me Anything episode of Mindscape! These monthly excursions are funded by Patreon supporters (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...

The course of history is affected by many things, including the political and social situations of large groups of people, their biological and physical abilities, and their geographical and environmental contexts. Sometimes, it would seem, history -- or corporations, or religions, or sports teams -- can be affected by the actions of just a few influential persons. In his new book, Profits, Prophe...

Everyone lives through time, but we continue to struggle to fully understand it. We remain unsure whether time is fundamental or emergent, why it has an arrow pointing from past to future, and how that arrow connects to our experience of time's passage. Jim Al-Khalili's new book is On Time: The Physics that Makes the Universe Tick . We discuss what time is at the most basic level, and how it conne...

Black holes, as Stephen Hawking discovered, do grow old: they emit radiation, lose mass, and eventually evaporate away. But our fascination with black holes never grows old. This is especially true today, as we are seeing a flood of new data and intriguing theoretical ideas, which both tests the limits of Einstein's general relativity and teach us new things about the astrophysical universe. At th...

One of the paradoxes of science is that it seeks objectively true understanding of the world, but its methodology is driven by ignorance, failure, and uncertainty. Some phenomena we understand pretty well, but interesting research happens at the boundary of what we do and don't know. And there is no foolproof algorithm for moving in the right direction; we need to make conjectures and test them ag...

Large Language Models display an uncanny ability to construct human-sounding speech, and can synthesize concepts in novel ways. Is this because they are truly thinking like human beings in some way, or have they found a way to be human-like without reproducing the internal mechanisms of human thought? Chandra Sripada argues that LLM cognition is more human-like than we suppose, and offers evidence...

Welcome to the August 2026 Ask Me Anything episode of Mindscape! These monthly excursions are funded by  Patreon supporters  (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...

People who live in large cities produce more patents per person than those who live in small towns. They also walk faster down the street, and use less infrastructure per person. Indeed, the relationships between these quantities and city population obey power laws with apparently universal exponents, reminiscent of scaling laws is biological organisms? Luis Bettencourt argues that they can be exp...

One of the characteristics of life is that living organisms gather information and put it to use. Even one of the simplest lifeforms, bacteria, are able to sense features of their surroundings and alter their behavior accordingly. Most impressively, they are able to sense the presence of similar bacteria by a process called  quorum sensing . Today's guest, Bonnie Bassler, is a leader in this field...

Welcome to the July 2026 Ask Me Anything episode of Mindscape! These monthly excursions are funded by  Patreon supporters  (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 th...

Modern life has, in many ways, removed us from the environments in which our ancestors lived and adapted. Not only do we spend time looking at screens, but we spend time indoors, or outdoors but in urban spaces. How does this affect how we think and feel? Psychologist Marc Berman is a pioneer of "environmental neuroscience." In his recent book,  Nature and the Mind: The Science of How Nature Impro...

The cosmological constant, as discussed last episode, provides a perfectly good (thus far) explanation for why we observe the universe to be accelerating. But it might not be the right explanation, and demonstrating that would be yet another foundational discovery. In this episode I discuss what is required to invent a plausible theory of dynamical  dark energy , This includes considerations from...

The most surprising discovery in fundamental physics during my career as a scientist was undoubtedly the  acceleration of the universe , announced in 1998. The most straightforward explanation for these observations is a positive cosmological constant, or vacuum energy. I talk about the origin of the idea with Einstein, how quantum physicists started to think about it and understand the "cosmologi...

Messenger RNA (mRNA) plays a literally central role in the functioning of life as we know it, shuttling information back and forth between the DNA where it is stored to the ribosome where it is used to produce proteins. RNA may even have been the first molecule to kick-start the origin of life. Today, scientists are learning how to manipulate mRNA to cure and prevent diseases, whether through vacc...

All ideas have a history, no matter how inevitable and well-entrenched they may seem to us today. The later Enlightenment was a heady time when people were exploring new conceptions of nature, humanity, and the self. Andrea Wulf is a writer of narrative histories, examining the origins of ideas through the lives of the people who explored them. In this episode we discuss three of her books:  The I...

Welcome to the June 2026 Ask Me Anything episode of Mindscape! These monthly excursions are funded by  Patreon supporters (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 the...

One of the major obstacles to understanding quantum mechanics is the difficulty we have in simply accepting what the theory itself is telling us. The problem is that we know what the everyday world looks like -- stuff, arranged in space, evolving through time. So we can't resist the temptation to impose that picture on the quantum description, even if it's not actually there. In this solo episode...

Did I have any freedom in choosing this particular podcast guest? At the level of particles, fields, and the fundamental laws of physics; no. At the level of human agents navigating the world, yes. Today's guest, Christian List, is a philosopher and political scientist who has arguably done the most to articulate the "compatibilist" perspective on free will, according to which the freedom of ratio...

Economic markets are efficient ways of deciding fair prices, at least in ideal circumstances of perfect competition, information, and choice. But there is more to life than fair prices. Two people might decide on a fair price to carry out a contract killing, but society generally frowns on the idea. Many examples of morally contestable markets feature less consensus than that one: sex work, drugs,...

Welcome to the May 2026 Ask Me Anything episode of Mindscape! These monthly excursions are funded by  Patreon supporters  (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 the...

The connectome is the wiring diagram of a brain, a big matrix that tells us what neurons talk to what other neurons. Understanding it is an important step to understanding how brains work, but a long way from the final answer. A big next step is understanding how neuronal circuits connect to and guide bodily behavior. Very recent work on mapping the fruit-fly connectome has brought us closer to th...