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

Quantum field theory is the basis for our most successful theories of fundamental physics. And yet, there are things we don't understand about it. Some of these puzzles are relatively well-known, while others are less celebrated. David Tong joins us to talk about some of the more interesting and perplexing aspects of quantum field theory. He also discusses his new project to write a series of text...

Welcome to the July 2025 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...

Our universe started out looking very simple: hot, dense, smooth, rapidly expanding. According to our best current model, it will end up looking simple once again: cold, dark, empty. It's in between -- now, roughly speaking -- that things look complex. I have been working to understand the stages by which complexity comes into existence, thrives, and eventually disappears. Without going into techn...

It is common to refer to philosophy as "a series of footnotes to Plato." But in the original quote, Alfred North Whitehead was more careful: he limited his characterization to "the European philosophical tradition." There are other traditions, both ancient and ongoing: Chinese philosophy, Indian philosophy, Africana philosophy, and various indigenous philosophies. For the most part, these do not g...

Economics is seeing an upsurge in the importance of controlled, reproducible empirical studies. One area where this has had a great impact is on development economics, which studies the economies of low- and middle-income societies. Edward Miguel has been at the forefront of both the revolution in empirical methods, and in applying those techniques to alleviating poverty in sub-Saharan Africa and...

The human brain is extremely complicated, but decades of careful neuroscientific research have revealed quite a bit about how it works, including how certain genes affect particular brain behaviors. Nevertheless, this progress has not led to quite as much improvement in the treatment of brain disorders as we might expect. I talk with neuroscientist Nicole Rust about why this is and how to improve...

Welcome to the June 2025 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...

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 assum...

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 u...

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 L...

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 unders...

Welcome to the May 2025 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 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 pasteuriz...

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 consci...

Welcome to the April 2025 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...

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 fo...

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 gues...

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...

Welcome to the March 2025 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...

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 t...

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...

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 account for these features. One phenomenon that has grown in recent years is an alignment of cultural differences with political ones,...

The Trump administration, 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 e...

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 fa...

Welcome to the February 2025 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 grou...