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Speaker 1: How does the universe work? What are the rules that

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Speaker 1: govern its most microscopic nature. For a few hundred years,

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Speaker 1: we've been making progress on this question, mostly by taking

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Speaker 1: things apart, and when we zoom into the universe at

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Speaker 1: the smallest level, it seems so far like there are

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Speaker 1: two different categories of particles, matter particles like quarks and electrons,

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Speaker 1: and force particles like photons and gluons. For a long time,

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Speaker 1: it seems like that has to be all there is.

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Speaker 1: What else could there possibly be? But experiments aren't the

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Speaker 1: only way to reveal the secrets of the universe. Another

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Speaker 1: very fruitful path is to follow the math. When we

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Speaker 1: ask what else the math allows, we sometimes get predictions

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Speaker 1: for very weird phenomena like antimatter, or black holes or

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Speaker 1: Higgs bosons, which turn out to be real in the universe.

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Speaker 1: So can the math show us another kind of particle?

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Speaker 1: A weird third way beyond matter and forces. Welcome to

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Speaker 1: Daniel and Kelly's Extraordinary mathematical Universe.

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Speaker 2: Hello, I'm Kelly Wiersmith. I study parasites and space, and

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Speaker 2: I think there are four kinds of particles.

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Speaker 3: Are parasites the fourth particle?

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Speaker 2: I mean if physics were any good, the answer would

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Speaker 2: be yes. See what I think is that y'all like symmetry,

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Speaker 2: and I think that if you decide there's three kinds

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Speaker 2: of particles, that will be an odd number and you'll

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Speaker 2: have to decide there's another kind, so that it's even Hi.

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Speaker 3: I'm Daniel.

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Speaker 1: I'm a particle physicist, not a paraparticle physicist or a

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Speaker 1: parasitical particle physicist or any.

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Speaker 3: Those other varieties.

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Speaker 1: But I do love understanding the nature of the universe

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Speaker 1: and finding symmetry in.

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Speaker 2: It all amazing. So are you one of those physicists

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Speaker 2: who feels like there needs to be symmetry in these

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Speaker 2: answers or does it just kind of depend on the topic?

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Speaker 1: Wow, what a deep question to drop on me at

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Speaker 1: the top of the episode. I think what we've learned

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Speaker 1: so far is that there is symmetry in the universe.

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Speaker 1: Like all the rules we've discovered about physics seem to

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Speaker 1: follow symmetric patterns. There's like reflections and translations, and you

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Speaker 1: can generalize this into abstract algebra called group theory. So

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Speaker 1: the universe seems to be well described by symmetries in mathematics.

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Speaker 1: Does that mean the universe is symmetric or that's just

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Speaker 1: the way we like to think about it. I mean,

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Speaker 1: that's a deep question in philosophy. We're not going to

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Speaker 1: answer it today. But I appreciate symmetry.

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Speaker 3: I love it. I love the mathematical beauty of what

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Speaker 3: we've learned about the universe.

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Speaker 2: Why should the universe be symmetrical instead of like just

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Speaker 2: a mess? Like as an evolutionary biologist, like it all

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Speaker 2: being held together with like duct tape and zip ties

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Speaker 2: makes more sense to me then it being beautifully symmetrical.

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Speaker 2: But why is it symmetrical?

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Speaker 1: I think I have a natural preference for explanations that

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Speaker 1: are simple, that are harmonious and parsimonious, right, Like we

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Speaker 1: think that the universe should be in the end described

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Speaker 1: by one simple idea, and so we're constantly looking for that,

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Speaker 1: and symmetry helps us restrain that. It helps us reduce

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Speaker 1: the number of options, you know, like instead of having

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Speaker 1: to come up with ten numbers, what if there's a

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Speaker 1: symmetry that tells you that those numbers are all related,

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Speaker 1: so there really is just one number that turns into ten.

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Speaker 1: But you might also ask the basic question like, well,

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Speaker 1: why do we expect the universe to be simple and parsimonious,

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Speaker 1: and I don't have an answer for that, you know,

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Speaker 1: just so far that seemed to work, you know, looking

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Speaker 1: for the simplest explanation so far has found us things

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Speaker 1: that work in the universe. They predict experiments, they describe

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Speaker 1: things we haven't seen yet. So many times in the

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Speaker 1: history of science we followed the symmetry in mathematics to

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Speaker 1: make discoveries like particles or like electromagnetism. You know, Maxwell

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Speaker 1: looking at these equations and seeing a lack of symmetry

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Speaker 1: and penciling in the piece he needs to make the

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Speaker 1: equation symmetrical, discovering something real in the universe, or Peter

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Speaker 1: Higgs finding a piece that clicks together with all the

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Speaker 1: other pieces to answer why symmetry is broken, so it

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Speaker 1: seems to work, is the only real answer I can

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Speaker 1: give you.

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Speaker 2: Interesting, you know, So I was I'm reading this book

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Speaker 2: called The Remedy right now, and it is about how

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Speaker 2: like Coch and Pasteur determined that microorganisms caused disease. And

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Speaker 2: the author was arguing that actually this kind of flew

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Speaker 2: in the face of we should look for the simplest answer,

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Speaker 2: because the simplest answer at the time was that bad

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Speaker 2: air causes all of these maladies, and so having one

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Speaker 2: cause that explained all of this stuff seemed much simpler

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Speaker 2: than you know, Tuberculosis is caused by this tiny organism,

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Speaker 2: and smallpox is caused by that tiny organism that we

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Speaker 2: can't even see. And so the fact that bad air

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Speaker 2: was simple a sort of made people cling to it

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Speaker 2: a little bit longer than this more complicated answer that

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Speaker 2: tended to be right. And so I think in almost

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Speaker 2: every case it makes a lot more sense to look

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Speaker 2: for the simplest explanation first, but you should not let

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Speaker 2: it close your eyes to the more complex answers that

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Speaker 2: might actually be the reality of the situation.

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Speaker 1: Yeah, you should choose the simplest answer that works, that

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Speaker 1: actually describes the universe. Yes, not the simplest answer that

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Speaker 1: doesn't describe the universe. But you're right, you don't know

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Speaker 1: in advance what's going to work and what isn't, And

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Speaker 1: so we often start from the simplest thing because why

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Speaker 1: not right, And if that doesn't work, then we move

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Speaker 1: on to something more complicated.

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Speaker 3: And that's how we get chemistry and biology and.

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Speaker 1: All sorts of other delicious, beautiful messes of science. Right,

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Speaker 1: that have yet to pull themselves together into a single

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Speaker 1: parsimonious explanation. And that's also one reason why I am

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Speaker 1: a physicist, because physics, I feel like, is closer to

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Speaker 1: getting to a single answer than chemistry is. For example,

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Speaker 1: I was always frustrated in chemistry, like this rule for

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Speaker 1: this thing, and this rule for that thing, and this

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Speaker 1: other rule except for this other scenario. Maybe I just

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Speaker 1: have a bad memory and it's hard to hold all

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Speaker 1: those things in my head. But I just really like

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Speaker 1: to look, here's one equation. Start from that you can

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Speaker 1: get to anything. That just always appealed to me.

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Speaker 2: That's so interesting. I think we live on very different

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Speaker 2: sides of this gradient. So like for me, you know,

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Speaker 2: you said biologists and chemists have yet to come up

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Speaker 2: with a simple theory. I don't feel like that's what

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Speaker 2: we're trying for at all.

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Speaker 1: Like why maybe that's why you haven't found one.

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Speaker 2: Why would you assume that there is one? Like life

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Speaker 2: is beautifully complex, you know, the it depends is where

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Speaker 2: all the fun lives. I think. You know, you're like, oh,

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Speaker 2: that's frustrating, and I'm like, no, that's that's the exciting part.

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Speaker 2: Like what it depends on what life is complicated and

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Speaker 2: messy and that's what makes it beautiful.

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Speaker 1: But isn't it beautiful when you find things that are

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Speaker 1: true across all of life? Right Like DNA, for example,

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Speaker 1: undergirds a lot of life on Earth, and that's really

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Speaker 1: powerful to discover that and to understand it. Right, Yeah,

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Speaker 1: it's not as fascinating as like this one kind of

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Speaker 1: frog does this one kind of thing on random tuesdays

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Speaker 1: in my opinion.

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Speaker 2: Well, I will politely disagree with you. I think what

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Speaker 2: the frogs are doing on tuesdays I am deeply interested in.

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Speaker 2: But yes, you know, I think it's beautiful that you know,

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Speaker 2: the blueprint for life is stored in the same material

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Speaker 2: no matter what organism you're looking at. But we all

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Speaker 2: do very different things with that material. You know, bacteria

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Speaker 2: do horizontal gene transfer. They're swapping genes back and forth,

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Speaker 2: and you know, we have to have sex to swap

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Speaker 2: genetic material, and we've got recombination and I don't know anyway,

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Speaker 2: that's where the it depends gets fun again.

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Speaker 1: Well, we have made a lot of hay in physics,

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Speaker 1: at least in looking for symmetries and then trying to

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Speaker 1: understand when there are holes, is there something to fill

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Speaker 1: that hole? Right the way we did with antiparticles and

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Speaker 1: the way we did with all the quarks, and so

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Speaker 1: often mathematical beauty really does lead us to new discoveries.

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Speaker 1: And that's what we're talking about today on the podcast.

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Speaker 1: Whether there is another bucket, another kind of thing out

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Speaker 1: there in the universe that we can use to describe

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Speaker 1: how everything works, maybe explains why those toads do that thing.

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Speaker 3: On Tuesday, at.

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Speaker 2: The end of all of our banters, I'm like, how

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Speaker 2: are we going to get back on track? And you

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Speaker 2: always get us there.

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Speaker 1: Okay, it's sometimes a bigger step than I expect.

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Speaker 4: But.

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Speaker 2: You're good at jumping that chasm. So all right. So

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Speaker 2: today we're talking about paraparticles and I had never heard

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Speaker 2: of para particles before, and so let's see if our

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Speaker 2: audience is on the same page as Kelly. So we asked,

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Speaker 2: what are para particles? And here are the answers we got.

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Speaker 4: I wonder if it's something to do with larger things

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Speaker 4: showing particle light behavior in certain circumstances. I'm so glad

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Speaker 4: there isn't. TONI exam at the end of the podcast.

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Speaker 2: Piece of a particle, like a very small part of

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Speaker 2: the particle, some sort of entity that exists alongside the

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Speaker 2: traditional particles.

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Speaker 3: Somewhere between a real particle and a ghost particle, like

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Speaker 3: a virtual particle, and then it's enabling interactions with others.

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Speaker 4: I think it's like a super superposition. And it's one

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Speaker 4: of those weird things about quantum mechanics that if you

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Speaker 4: look at it, it just disappears off.

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Speaker 2: I might be particles that we believe exist but haven't

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Speaker 2: I prayed for yet.

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Speaker 3: Kind of like a particle but not quite.

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Speaker 2: Something that acts like a particle when certain conditions are.

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Speaker 3: Met at something that's almost a particle. Paraparticles rely on

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Speaker 3: their neighboring particle for existence. I'm completely stunned by this one.

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Speaker 2: The virtual particle pairs that spring to existence in a vacuum.

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Speaker 2: Is a paraparticle something that lives off of or takes

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Speaker 2: advantage of another particle?

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Speaker 3: Is it a paralyzed particle?

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Speaker 2: So lots of playing with what para means in other contexts.

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Speaker 2: I like it got you all are very clever.

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Speaker 1: But they missed the obvious. Nobody went for the connection

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Speaker 1: to parasites.

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Speaker 2: Guys, Guys, I work so oft hard so hard. Oh wait, no, no, no,

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Speaker 2: that's not true. Somebody said, relying on their neighbors for existence,

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Speaker 2: that's their parasitical particles. That's right way to go, that

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Speaker 2: particular audience member. Thank you for paying attention all this time.

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Speaker 1: I was just glad that nobody went for the sort

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Speaker 1: of anti academic grifter line, the like academics are just

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Speaker 1: parasites on society and they're sucking money and scams and

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Speaker 1: don't really believe anything they're doing, all that bad faith

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Speaker 1: nonsense you sometimes see in various corners of the internet.

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Speaker 2: Oh wow, are you I feel like there's a bit

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Speaker 2: of insecurity today.

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Speaker 1: I just want to address the reality, you know, that

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Speaker 1: kind of stuff is out there in the universe. Anyway,

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Speaker 1: I was very happy to hear all these positive and

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Speaker 1: constructive answers. Thanks everybody. If you'd like to contribute your

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Speaker 1: ideas for future episodes, don't be shy right to us

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Speaker 1: two questions at Daniel and Kelly dot org. You can

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Speaker 1: hear your voice on the podcast.

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Speaker 2: Amazing. All right, So let's dig in. So what are

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Speaker 2: a particle? So you said in the introduction that there

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Speaker 2: are maybe three kinds of particles. Can we start by

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Speaker 2: reviewing the first two kinds, because I'm sure that you've

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Speaker 2: mentioned in the past that particles come in matter and

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Speaker 2: force flavors. But every once in a while, at the

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Speaker 2: end of an episode, I'll discover my brain has reached

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Speaker 2: capacity and maybe some stuff overflowed out the top, and

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Speaker 2: so remind me what are meta particles? What are force particles?

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Speaker 2: And then we'll get into this third kind.

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Speaker 3: Yeah, sure, no problem. I'd be careful with the word flavor.

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Speaker 1: Though flavor has a particular meaning in particle physics, it

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Speaker 1: means something else, and it's not like you know, cookie

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Speaker 1: dough and mint chocolate chip. It's like the difference between

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Speaker 1: electrons and muons and towels or different flavors of leptons.

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Speaker 2: Like that's an actual like physics jargon term is flavors.

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Speaker 1: Oh absolutely, And there's amazing the whole subfield of particle

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Speaker 1: physics called flavor physics. And then the people who work

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Speaker 1: on the flavor of particles that have a lot of mass,

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Speaker 1: that's called heavy flavor physics, which sounds like it should

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Speaker 1: be a hip hop group, but it really is a

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Speaker 1: bunch of nerds.

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Speaker 2: Well, you know, nerds can have hip hop groups. You

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Speaker 2: don't have to be so judgy.

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Speaker 3: Yeah, heavy flavor flakes, let's hear it.

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Speaker 2: I love it.

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Speaker 3: All right.

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Speaker 1: So today we're talking about one way to distinguish particles,

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Speaker 1: and that's by their spin. So there are particles that

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Speaker 1: make up matter, me and you, and everything that's out

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Speaker 1: there and everything you've ever eaten are made out of

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Speaker 1: quarks and lectons. So the upcork and the down cork

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Speaker 1: make up protons and neutrons. You add electrons, which are

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Speaker 1: kind of lefton, and you can make any atom. Right

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Speaker 1: from that, you can make any molecule. And anything anybody

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Speaker 1: has ever seen or thrown at their sister is made

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Speaker 1: out of this kind of stuff, right, Okay, So this

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Speaker 1: is what we call matter particles. And all these particles

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Speaker 1: have something in common, which is their quantum spin has

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Speaker 1: units of one half, which means they can have spin

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Speaker 1: up one half or spin down one half. So all

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Speaker 1: these particles, which we call fermions after Enrico Fermi, these

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Speaker 1: are matter particles. They're particles with one half spin.

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Speaker 2: Can you help me like visualize that, like, are they

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Speaker 2: actually spinning?

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Speaker 1: M You know the answer to that question, Kelly is

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Speaker 1: nobody knows. Quantum spin is a super fascinating topic because

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Speaker 1: on one hand, it's very different from a real spin,

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Speaker 1: like normal spin, like you take a ball and you

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Speaker 1: spin it. We can talk about the angular momentum, we

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Speaker 1: can talk about the velocity on the surface. A classical

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Speaker 1: object has spin and it has angular momentum, right, And

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Speaker 1: we know that that angler momentum is important to the

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Speaker 1: universe because it's preserved. Like if you spin a ball

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Speaker 1: in space, it keeps spinning. And the reason that like

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Speaker 1: our galaxy is spinning is because of conservation of angular momentum.

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Speaker 1: The reason the solar system has the shape that it does,

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Speaker 1: it's like sort of flat. The way the galaxy is

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Speaker 1: a disc is because of angle momentum. Anglementum is a

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Speaker 1: really big important thing in the universe. Things really do spin.

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Speaker 1: Quantum particles don't spin in the same way because electrons

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Speaker 1: are not tiny little balls. And like one hundred years ago,

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Speaker 1: when they were thinking about this, they were like, well,

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Speaker 1: what if they spin, how fast would they be spin?

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Speaker 1: They try to calculate, like how fast the surface of

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Speaker 1: an electron is spinning, and you get an answer that's

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Speaker 1: like higher than the speed of light. So it's obviously nonsense.

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Speaker 1: Whenever you do physics and you get an answer that

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Speaker 1: doesn't make sense, like something has gone wrong along the

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Speaker 1: way right.

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Speaker 2: Or you've created a new field.

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Speaker 1: In this case, the answer is that these are quantum particles.

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Speaker 1: They're not classical, so you can think of them as

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Speaker 1: existing physically the same way, where every part of them

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Speaker 1: has a location every moment in time, so they don't

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Speaker 1: physically spin. You shouldn't think about these quantum particles as

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Speaker 1: like little balls that are spinning, and so you might ask, well,

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Speaker 1: if it's not spinning, why do you call it spin.

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Speaker 1: We call it spin because it has a lot of

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Speaker 1: the same properties as classical objects spin. For example, it's

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Speaker 1: conserved right, and it's conserved together with other kinds of

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Speaker 1: angular momentum, meaning that what the universe cares about is

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Speaker 1: the total angler momentum, including spin. So you can convert

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Speaker 1: like normal angler momentum like the Earth is spinning, into

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Speaker 1: quantum angle momentum spin, and back and forth. The universe

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Speaker 1: requires you to conserve the sum of those two, which

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Speaker 1: tells you they're like the same kind of thing the

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Speaker 1: same way that like energy is often conserved, but it's

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Speaker 1: the sum of kinetic and potential energies. Which tells you like, Okay,

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Speaker 1: these are two kinds of the same thing, because what

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Speaker 1: the universe cares about is the sum of them, not

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Speaker 1: the individual ones. So we know that quantum spin is

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Speaker 1: similar to real spin classical spin because the universe conserves

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Speaker 1: the sum of those things, and quantum spin has other

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Speaker 1: similar properties, like things that have quantum spin and electric

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Speaker 1: charge have little magnetic fields because charges in motion give

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Speaker 1: magnetic fields. So like an electron which is spinning, has

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Speaker 1: a little magnetic field, and that's why it's like bent

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Speaker 1: by magnetic fields, et cetera, et cetera. So we don't

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Speaker 1: really know what it is, but we know that it

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Speaker 1: acts a lot like spin, so we call it quantum spin,

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Speaker 1: which I think is a pretty good name, even though

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Speaker 1: it's not spinning.

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Speaker 2: Okay, all right, So I usually to hear things like

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Speaker 2: four times before they stick in my brain. I think

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Speaker 2: we're at like two, so be prepared to repeat that.

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Speaker 2: But so to try to help me, all right, So, fermions,

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Speaker 2: these are the mass or the matter particles. Yes, and

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Speaker 2: so I'm gonna think of fermions as like it's firm matter.

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Speaker 2: It makes us be although you know now you're gonna

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Speaker 2: misspell fermions from here on out because it's not spelled

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Speaker 2: like firm. But anyway, all right, that's how I'm remembering it.

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Speaker 2: And so now let's talk about force. And so I

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Speaker 2: always thought force was like a field, and I didn't

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Speaker 2: think of it as a particle anyway. So let's go on.

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Speaker 2: So the bosons are force particles.

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Speaker 1: Yes, And let me also liabrate on the comment you

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Speaker 1: made about field versus particles. There are two ways of

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Speaker 1: thinking about what stuff is and how it's pushed. One

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Speaker 1: is the field picture, which is really natural to a

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Speaker 1: lot of particle physicists. There's an electron field, and the

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Speaker 1: electron is actually just a ripple in that field, and

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Speaker 1: there's an electromagnetic field, and photons are ripples in that field.

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Speaker 1: And in that view, the fields are the fundamental thing,

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Speaker 1: and particles are just ripples in those things. They are

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Speaker 1: like emerging phenomena from the fields, and the fields can interact.

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Speaker 1: And we talk about that picture a lot on the podcast.

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Speaker 1: There's another way to think about things and say, you know,

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Speaker 1: fields are just like a construct in our minds. We

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Speaker 1: never see them directly. We only see them acting on particles,

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Speaker 1: and the particles are the things we can see. We

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Speaker 1: see dots on the screen, we see electrons moving through wires, etc.

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Speaker 1: So particles are the real things. And so from that

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Speaker 1: point of view, we have electrons and they're little particles,

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Speaker 1: and we have quarks and their little particles, and then

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Speaker 1: the forces we can talk about other particles. So we

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Speaker 1: have like the photon. What happens when two electrons repel

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Speaker 1: each other, they exchange photons. So this is the particle

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Speaker 1: picture of the universe. Everything is made out of little particles,

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Speaker 1: and it can explain matter. It's a little bit more awkward,

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Speaker 1: but it can also explain forces right in that picture,

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Speaker 1: like electrons exchange photons. That's the way they attract or

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Speaker 1: repel each other. And it's a little bit awkward because

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Speaker 1: like how exactly they do electrons and positrons attract each

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Speaker 1: other by exchanging photons.

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Speaker 3: It's hard to imagine you.

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Speaker 1: Could like attract Zach by throwing a ball at him, right,

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Speaker 1: it feels like it would only push him away. But

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Speaker 1: you know, this is the quantum world, and you can

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Speaker 1: do weird things like you can throw a photon with

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Speaker 1: negative momentum, so when Zach catches it, he's pulled towards you.

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Speaker 1: It's like a tractor beam photon.

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Speaker 2: And biology is too complicated, doesn't make sense. What are

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Speaker 2: you guys thinking?

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Speaker 1: Yeah, yeah, And this is one reason why I think

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Speaker 1: the field picture is a little bit more natural.

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Speaker 3: But anyway, we can.

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Speaker 1: Talk about these forces as mediated by particles. And these

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Speaker 1: particles have a property which is that they don't have

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Speaker 1: half integer spin like one half or negative one half.

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Speaker 1: They have integer spin. So a photon, for example, can

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Speaker 1: have spin one, spin zero or spin negative one. And

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Speaker 1: the W boson and the Z boson, and the Higgs

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Speaker 1: boson and the gluons, all the particles that correspond to

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Speaker 1: the forces and how matter particles exchange momentum, they all

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Speaker 1: have the same property that their spin is integer values,

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Speaker 1: you know, half it's like plus two minus one, this

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Speaker 1: kind of stuff. So those are particles we call bosons.

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Speaker 1: So the fermions and the matter particles, the bosons are

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Speaker 1: the force particles in this picture.

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Speaker 2: All right, So now we've got through the two kinds

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Speaker 2: of particles, and let's bring a little bit of pep

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Speaker 2: into this conversation after the break, So we'll talk about

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Speaker 2: the Paul exclusion principle when we get back all right,

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Speaker 2: So we've established that we have two kinds of particles.

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Speaker 2: We've got the fermions, which are the matter particles, and

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Speaker 2: the bosons, which are the force particles. Why does it

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Speaker 2: matter that we divide them in this way? Why can't

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Speaker 2: they all just be particles.

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Speaker 1: They are all just partticles or fields equivalently, but they

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Speaker 1: have very different behaviors, and that behavior is really important. Specifically,

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Speaker 1: bosons can do something fermions will never ever ever do,

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Speaker 1: which is, bosons can be in the same quantum state

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Speaker 1: and fermions never will. So you made this joke about PEP.

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Speaker 1: The poly exclusion principle, named after Wolfgunning Poll says that

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Speaker 1: no two fermions can ever be in the same quantum state.

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Speaker 1: So if you have two identical particles like two electrons,

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Speaker 1: they can't have all the same quantum description, which would

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Speaker 1: be like their location, their momentum, their spin, their energy,

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Speaker 1: all this kind of stuff. They can't be identical. They

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Speaker 1: have to be unique. Every fermion has to have a

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Speaker 1: different quantum state.

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Speaker 2: Does it make sense to think of that? So our

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Speaker 2: fermions are our matter particles. Does it make sense to

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Speaker 2: think of it as like two pieces of matter can't

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Speaker 2: take up the same space. Or this is like a

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Speaker 2: totally different thing than thinking about it that way.

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Speaker 1: Two pieces of matter can't up the same space as

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Speaker 1: long as they have something to differentiate them. So, for example,

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Speaker 1: electrons have two possible spins right, spin up and spin down.

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Speaker 1: So in the ground state of an atom, for example,

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Speaker 1: you can have two electrons with exactly the same energy,

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Speaker 1: the same momentum, the same location, the same energy, the

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Speaker 1: same everything, but one is spin up and the other

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Speaker 1: is spin down. That's why you have two electrons in

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Speaker 1: the lowest state. That's where that two comes from. Because

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Speaker 1: there are two options for spin. You can't have two

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Speaker 1: electrons both spin up, and you can't have two electrons

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Speaker 1: both spin down.

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Speaker 3: Because of this poly.

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Speaker 1: Exclusion principle, it says you can never have two electrons

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Speaker 1: in the same state, and that's why you don't get

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Speaker 1: all of the electrons in the ground state. If you

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Speaker 1: already have two electrons in that ground state, it's full.

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Speaker 1: It can't take anymore. There's no third spin right, So

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Speaker 1: when another electron comes along, it has to have a

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Speaker 1: higher energy, has to be in the next energy level

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Speaker 1: because the lowest rungs are filled and it's one electron

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Speaker 1: per unique state, right, So the lowest energy level has

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Speaker 1: two of those. The next one, because has more energy,

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Speaker 1: has more options for like where the electron it is

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Speaker 1: around the atom this p state. Now we're getting deep

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Speaker 1: into chemistry, some beyond my expertise right away. But that's

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Speaker 1: why you can have more electrons in that second one,

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Speaker 1: and then more in the third level and more in

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Speaker 1: the fourth because there's more options for differentiating exactly which

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Speaker 1: version of that energy level you're in. And this is

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Speaker 1: why we have chemistry. This is why gold looks the

437
00:22:26,720 --> 00:22:28,920
Speaker 1: way it does. This is why we have water, this

438
00:22:28,960 --> 00:22:32,119
Speaker 1: is why atoms bind together. This is why our whole

439
00:22:32,280 --> 00:22:36,479
Speaker 1: universe looks the way that it does, because fermions cannot

440
00:22:36,480 --> 00:22:37,359
Speaker 1: be in the same state.

441
00:22:37,680 --> 00:22:41,199
Speaker 2: Now, is this an observation of what's happening or do

442
00:22:41,280 --> 00:22:44,640
Speaker 2: we understand why it has to be that way.

443
00:22:45,240 --> 00:22:47,520
Speaker 1: It's still a little bit mysterious, Like, it's definitely an

444
00:22:47,560 --> 00:22:51,400
Speaker 1: observation and we've never ever seen it violated. And if

445
00:22:51,440 --> 00:22:53,840
Speaker 1: it was violated, like the whole universe would look different,

446
00:22:53,840 --> 00:22:56,440
Speaker 1: Like if somebody turned this rule off and said, hey, fermeons,

447
00:22:56,520 --> 00:22:59,080
Speaker 1: no problem. You can now share a state. All of

448
00:22:59,119 --> 00:23:00,000
Speaker 1: matter would collapse.

449
00:23:00,720 --> 00:23:03,440
Speaker 2: Bad news exactly, it would.

450
00:23:03,200 --> 00:23:04,880
Speaker 1: Be bad news. So I don't recommend it. If you're

451
00:23:04,920 --> 00:23:06,800
Speaker 1: sitting in the Universe control room and you have your

452
00:23:06,840 --> 00:23:10,520
Speaker 1: finger on that knob, call me please before you do anything.

453
00:23:11,119 --> 00:23:13,879
Speaker 1: We do have some handwavy explanations for why it is.

454
00:23:14,440 --> 00:23:17,040
Speaker 1: We don't have a really full formal proof. We can't

455
00:23:17,040 --> 00:23:20,760
Speaker 1: go from like, here are the fields, here's how Fermions

456
00:23:20,760 --> 00:23:23,600
Speaker 1: will behave. What we can do is prove the negative,

457
00:23:23,760 --> 00:23:27,680
Speaker 1: like we can show why Fermions can't do this thing,

458
00:23:28,440 --> 00:23:30,560
Speaker 1: Like we can show that if Fermions did this thing,

459
00:23:30,880 --> 00:23:33,320
Speaker 1: it would lead to some contradictions. So I'm trying to

460
00:23:33,320 --> 00:23:36,280
Speaker 1: walk you through a handwavy version of that proof in

461
00:23:36,320 --> 00:23:40,439
Speaker 1: a minute. But we couldn't have started from scratch and

462
00:23:40,640 --> 00:23:44,560
Speaker 1: really shown how this happens. And Fineman famously said that

463
00:23:44,560 --> 00:23:46,840
Speaker 1: we don't have a full proof, and also it's really

464
00:23:46,920 --> 00:23:50,679
Speaker 1: challenging to give an intuitive explanation for this because quote,

465
00:23:50,720 --> 00:23:53,399
Speaker 1: we do not have a complete understanding of the fundamental

466
00:23:53,400 --> 00:23:56,879
Speaker 1: principle involved. Finan was big on this theory that like,

467
00:23:57,040 --> 00:24:00,240
Speaker 1: if you can't explain it simply, you don't really understand it,

468
00:24:00,840 --> 00:24:03,400
Speaker 1: which I think is really interesting as a hypothesis because

469
00:24:03,400 --> 00:24:05,040
Speaker 1: it kind of lines up with what we were talking

470
00:24:05,040 --> 00:24:08,400
Speaker 1: about earlier, and it touches on something we were talking about,

471
00:24:08,440 --> 00:24:10,479
Speaker 1: I think on the discord of like how on this

472
00:24:10,520 --> 00:24:13,359
Speaker 1: pod we're constantly trying to explain complicated stuff in an

473
00:24:13,359 --> 00:24:15,800
Speaker 1: intuitive way. Without all the math. You can't just be like,

474
00:24:15,960 --> 00:24:17,960
Speaker 1: here's a bunch of math. This math tells you what

475
00:24:18,000 --> 00:24:20,520
Speaker 1: the answer is. We want to tell a story that

476
00:24:20,640 --> 00:24:23,399
Speaker 1: connects with the ideas in your head, so you go, oh,

477
00:24:23,680 --> 00:24:24,440
Speaker 1: that makes sense.

478
00:24:24,560 --> 00:24:25,000
Speaker 3: I get it.

479
00:24:25,119 --> 00:24:27,719
Speaker 1: Why it's this way and not the other way. And

480
00:24:27,760 --> 00:24:31,680
Speaker 1: that's very different from the mathematical explanation or concepts that

481
00:24:31,720 --> 00:24:33,959
Speaker 1: we often have in academia and we teach in college

482
00:24:34,000 --> 00:24:36,040
Speaker 1: and in graduate school, and that most physicists have in

483
00:24:36,080 --> 00:24:39,959
Speaker 1: their minds. This is like an intuitive grasp of something

484
00:24:40,320 --> 00:24:42,560
Speaker 1: you have to develop in order to explain it and

485
00:24:42,640 --> 00:24:44,960
Speaker 1: find me is saying that without that extra piece, this

486
00:24:45,160 --> 00:24:49,159
Speaker 1: like parallel explanation, that's intuitive, you don't really understand it.

487
00:24:49,560 --> 00:24:52,080
Speaker 1: And I think that's fascinating and maybe correct. But it's

488
00:24:52,280 --> 00:24:54,720
Speaker 1: a pretty strong statement of philosophy for a guy who

489
00:24:54,760 --> 00:24:56,360
Speaker 1: was famously against philosophy.

490
00:24:56,680 --> 00:24:59,040
Speaker 2: Yeah, and how do you think he would feel about

491
00:24:59,080 --> 00:25:02,080
Speaker 2: the current state of things today. Although I'm gonna go

492
00:25:02,080 --> 00:25:04,280
Speaker 2: ahead and admit that I hate questions where they're like,

493
00:25:04,280 --> 00:25:06,520
Speaker 2: what do you think Benjamin Franklin would think about blah

494
00:25:06,560 --> 00:25:09,159
Speaker 2: blah blah. It's like, I'm not Benjamin Franklin, and if

495
00:25:09,240 --> 00:25:11,040
Speaker 2: he was raised in our time, you might feel totally

496
00:25:11,080 --> 00:25:11,960
Speaker 2: different about things.

497
00:25:12,160 --> 00:25:15,040
Speaker 1: Yeah, Feineman is a complicated character because, on one hand,

498
00:25:15,560 --> 00:25:19,879
Speaker 1: super genius dude, lots of important insights, also lots of

499
00:25:19,920 --> 00:25:23,399
Speaker 1: great explanations, and he did something which I think is

500
00:25:23,440 --> 00:25:26,159
Speaker 1: really impressive that I've never seen before, which is he

501
00:25:26,200 --> 00:25:27,840
Speaker 1: came up with an explanation of or a concept in

502
00:25:27,840 --> 00:25:30,720
Speaker 1: this case Nuther's theorem in one of his popular books,

503
00:25:30,760 --> 00:25:35,240
Speaker 1: like for a popular Audience, and that explanation then got

504
00:25:35,240 --> 00:25:38,760
Speaker 1: transformed into a full rigorous proof, which is now the

505
00:25:38,760 --> 00:25:42,120
Speaker 1: go to rigorous proof you find in like formal physics books.

506
00:25:42,560 --> 00:25:44,520
Speaker 1: Usually things go the other way, you like, start with

507
00:25:44,520 --> 00:25:47,200
Speaker 1: a full rigorous proof and then you develop the intuitive explanation.

508
00:25:47,560 --> 00:25:49,720
Speaker 1: But he actually came up with it for the general

509
00:25:49,800 --> 00:25:52,760
Speaker 1: public and then it turned into a rigorous proof, So

510
00:25:52,840 --> 00:25:55,159
Speaker 1: that's pretty cool. Like, the guy definitely had talents and

511
00:25:55,200 --> 00:25:58,639
Speaker 1: lots of different directions. He's also famously kind of a jerk,

512
00:25:59,640 --> 00:26:02,680
Speaker 1: and so it's sort of a problematic figure in that sense.

513
00:26:02,720 --> 00:26:04,399
Speaker 1: I think if finally we're a lot today, he probably

514
00:26:04,400 --> 00:26:06,640
Speaker 1: would feel grumpy that people had come up with stuff

515
00:26:06,640 --> 00:26:07,120
Speaker 1: without him.

516
00:26:09,040 --> 00:26:11,960
Speaker 3: Great, I don't know Hardy.

517
00:26:12,160 --> 00:26:15,000
Speaker 2: Well, he's in our past. He's in the rear view mirror. Okay.

518
00:26:15,080 --> 00:26:19,240
Speaker 2: So we have observed that fermions don't occupy the same state.

519
00:26:19,520 --> 00:26:21,680
Speaker 2: We kind of understand why it would be nice to

520
00:26:21,760 --> 00:26:22,520
Speaker 2: understand better.

521
00:26:22,920 --> 00:26:26,119
Speaker 1: And we've observed that bosons can, right. We see this

522
00:26:26,240 --> 00:26:29,159
Speaker 1: all the time. Like you put two photons in a box,

523
00:26:29,240 --> 00:26:31,520
Speaker 1: they're very happy to sit right on top of each

524
00:26:31,560 --> 00:26:34,359
Speaker 1: other to be in exactly the same state. And this

525
00:26:34,440 --> 00:26:38,120
Speaker 1: lets you do things like make Bose Einstein condensates and

526
00:26:38,520 --> 00:26:42,800
Speaker 1: macroscopic objects that have quantum properties because all the photons

527
00:26:42,800 --> 00:26:44,639
Speaker 1: are in the same state, and you can't do that

528
00:26:44,680 --> 00:26:46,840
Speaker 1: with electrons. You put too many electrons together, they get

529
00:26:46,840 --> 00:26:48,800
Speaker 1: this degeneracy pressure. They don't want to be in the

530
00:26:48,800 --> 00:26:51,119
Speaker 1: same lowest state, so some of them have to be

531
00:26:51,160 --> 00:26:53,360
Speaker 1: in a higher energy state, and that's where you get

532
00:26:53,400 --> 00:26:57,440
Speaker 1: like pressure. That's why like white dwarves don't collapse because

533
00:26:57,440 --> 00:27:00,240
Speaker 1: the electrons inside them if they collapse would have to

534
00:27:00,320 --> 00:27:02,080
Speaker 1: end up being in the same lower energy state, and

535
00:27:02,080 --> 00:27:04,520
Speaker 1: they resist that they can't do it, and so like,

536
00:27:04,600 --> 00:27:07,560
Speaker 1: this has real impact in the universe, and it affects

537
00:27:07,600 --> 00:27:09,840
Speaker 1: how we do experiments and all sorts of stuff. And

538
00:27:09,880 --> 00:27:13,119
Speaker 1: so this is definitely real and we have some understanding

539
00:27:13,280 --> 00:27:13,760
Speaker 1: of how it.

540
00:27:13,720 --> 00:27:14,560
Speaker 3: Works, all right.

541
00:27:14,600 --> 00:27:19,840
Speaker 2: So fermions are our introverts and the bosons are our extroverts.

542
00:27:22,080 --> 00:27:24,399
Speaker 1: Electrons just want to be in their own house, like

543
00:27:24,440 --> 00:27:27,040
Speaker 1: watching their own TV show at night by themselves, and

544
00:27:27,080 --> 00:27:28,760
Speaker 1: photons are always up for a party.

545
00:27:29,040 --> 00:27:31,679
Speaker 2: Okay, So now we have a pretty good understanding of

546
00:27:32,200 --> 00:27:34,399
Speaker 2: fermions and bosons and what they can and can't do.

547
00:27:35,040 --> 00:27:36,840
Speaker 2: How do we get from here to paraparticles?

548
00:27:37,119 --> 00:27:37,480
Speaker 3: All right?

549
00:27:37,560 --> 00:27:41,200
Speaker 1: So to understand how paraparticles might fit into this picture,

550
00:27:41,280 --> 00:27:44,240
Speaker 1: because it sounds like there are only two options. Either

551
00:27:44,320 --> 00:27:47,160
Speaker 1: you have half into your spin, you know, one half,

552
00:27:47,200 --> 00:27:49,840
Speaker 1: three halves, five halves, or you have into your spin

553
00:27:50,040 --> 00:27:53,400
Speaker 1: zero one, two, three, whatever. What's another option? How could

554
00:27:53,440 --> 00:27:55,080
Speaker 1: you possibly have a third category?

555
00:27:55,200 --> 00:27:55,440
Speaker 3: Right?

556
00:27:55,800 --> 00:27:57,600
Speaker 1: And that was the prevailing wisdom for a long long

557
00:27:57,640 --> 00:28:01,600
Speaker 1: time until very recently. But to understand where the loophole is,

558
00:28:01,640 --> 00:28:05,120
Speaker 1: we've got to dig one level deeper into understanding why

559
00:28:05,160 --> 00:28:08,720
Speaker 1: fermions behave this way and why bosons behave the other way.

560
00:28:09,240 --> 00:28:11,280
Speaker 1: So we're going to go through this sort of rough

561
00:28:11,320 --> 00:28:14,920
Speaker 1: and imperfect proof of the poly exclusion principle to explain

562
00:28:15,040 --> 00:28:18,120
Speaker 1: why fermions behave one way and bosons the other way.

563
00:28:18,240 --> 00:28:20,000
Speaker 2: Daniel's got pep, All right, let's do that.

564
00:28:22,520 --> 00:28:26,720
Speaker 1: All right, So imagine two particles, particle one and particle two.

565
00:28:26,640 --> 00:28:29,480
Speaker 2: In typical physicist fashion. Those are very boring names for them, but.

566
00:28:29,520 --> 00:28:33,680
Speaker 1: Okay, okay, let's make them exciting names.

567
00:28:34,280 --> 00:28:36,479
Speaker 3: What would be exciting names for these particles? Now?

568
00:28:36,600 --> 00:28:38,720
Speaker 2: Feeling if we name them like Frank and Rita, it's

569
00:28:38,720 --> 00:28:41,600
Speaker 2: gonna be hard to keep track. Maybe one and two

570
00:28:41,760 --> 00:28:42,560
Speaker 2: was a good idea.

571
00:28:43,040 --> 00:28:48,440
Speaker 1: Okay, wow, that doctor criticism pretty quickly there. Alright, alright, alright,

572
00:28:48,480 --> 00:28:51,040
Speaker 1: so particle boring one in particle boring.

573
00:28:50,760 --> 00:28:51,520
Speaker 2: Two, all right.

574
00:28:51,760 --> 00:28:53,840
Speaker 1: Now, each of them can do one thing, right now,

575
00:28:53,920 --> 00:28:55,720
Speaker 1: They have two different options. They can be in state

576
00:28:55,760 --> 00:28:59,560
Speaker 1: A or state B. Okay, so particle A can do

577
00:28:59,600 --> 00:29:01,200
Speaker 1: two things. It can be in state A or it

578
00:29:01,240 --> 00:29:03,200
Speaker 1: can be in state B. Particle two can also be

579
00:29:03,240 --> 00:29:06,040
Speaker 1: in state A or state B. And then we can

580
00:29:06,040 --> 00:29:08,280
Speaker 1: describe the full quantum state of the pair of the

581
00:29:08,280 --> 00:29:12,200
Speaker 1: particles as saying like one A two B. That means

582
00:29:12,200 --> 00:29:14,960
Speaker 1: particle one is in state A, in particle two is

583
00:29:15,000 --> 00:29:15,760
Speaker 1: in state B.

584
00:29:16,120 --> 00:29:19,360
Speaker 2: Right, you could also have one B and two A, right,

585
00:29:19,400 --> 00:29:19,680
Speaker 2: and I.

586
00:29:19,640 --> 00:29:23,520
Speaker 1: Understanding absolutely exactly, And so let's do that. Let's take

587
00:29:23,520 --> 00:29:26,400
Speaker 1: our particles one A to B and let's swap them.

588
00:29:26,720 --> 00:29:30,160
Speaker 1: These are identical particles, okay, there's nothing different about them.

589
00:29:30,160 --> 00:29:32,200
Speaker 1: Every electron in the universe, for example, is the same.

590
00:29:32,840 --> 00:29:35,440
Speaker 1: And so let's just swap them. So we go from

591
00:29:35,480 --> 00:29:39,160
Speaker 1: one A to B to one B two A. Right now,

592
00:29:39,200 --> 00:29:42,640
Speaker 1: the quantum field theory of fermions, the math of fermions,

593
00:29:42,680 --> 00:29:45,960
Speaker 1: because they have spin one half. When you do this,

594
00:29:46,320 --> 00:29:49,160
Speaker 1: you get a minus sign. So you can't go from

595
00:29:49,160 --> 00:29:51,480
Speaker 1: one A to B just to one B two A.

596
00:29:52,120 --> 00:29:55,440
Speaker 1: You go to minus one B two A. You get

597
00:29:55,480 --> 00:29:59,160
Speaker 1: a negative sign in front of the quantum state. And

598
00:29:59,200 --> 00:30:01,800
Speaker 1: this has to do with what happens when you're swapping

599
00:30:01,840 --> 00:30:04,200
Speaker 1: them and you're making a face that tells me I

600
00:30:04,240 --> 00:30:05,760
Speaker 1: need to pause so you can ask a question.

601
00:30:06,680 --> 00:30:10,080
Speaker 2: Okay, So we said that you can have one A

602
00:30:10,320 --> 00:30:14,240
Speaker 2: to B as one state, and you can have one

603
00:30:14,280 --> 00:30:17,280
Speaker 2: B two A as another state. Yes, but I thought

604
00:30:17,320 --> 00:30:19,800
Speaker 2: that you were saying that, actually, you can't have one

605
00:30:19,840 --> 00:30:22,080
Speaker 2: B two A. It has to be negative one B

606
00:30:22,160 --> 00:30:22,480
Speaker 2: two A.

607
00:30:22,960 --> 00:30:24,959
Speaker 1: You can have one B two ah. Okay, but if

608
00:30:25,000 --> 00:30:27,080
Speaker 1: you start with one A two B and then you

609
00:30:27,160 --> 00:30:29,680
Speaker 1: swap them, you don't end up at one B two A,

610
00:30:29,840 --> 00:30:32,640
Speaker 1: which you end up with is negative one B two A.

611
00:30:32,960 --> 00:30:33,280
Speaker 2: Okay.

612
00:30:33,640 --> 00:30:36,200
Speaker 1: That's like saying, you know, take your driver's license and

613
00:30:36,720 --> 00:30:39,400
Speaker 1: or flip it around right, you don't necessarily get it

614
00:30:39,440 --> 00:30:41,800
Speaker 1: in this exactly the same orientation depending on how you

615
00:30:41,840 --> 00:30:42,280
Speaker 1: spin it.

616
00:30:42,400 --> 00:30:42,600
Speaker 3: Right.

617
00:30:43,120 --> 00:30:45,680
Speaker 1: Some things like a sphere, doesn't matter how you spin it,

618
00:30:45,680 --> 00:30:48,040
Speaker 1: you end up with exactly the same sphere as perfect symmetry.

619
00:30:48,560 --> 00:30:51,800
Speaker 1: Other things have like a handedness or an orientation right,

620
00:30:51,800 --> 00:30:54,440
Speaker 1: like or take your left hand and turn it around.

621
00:30:54,520 --> 00:30:56,960
Speaker 1: It doesn't look exactly like your right hand. Right, maybe

622
00:30:56,960 --> 00:30:59,000
Speaker 1: it looks like a mirror image of your right hand.

623
00:30:59,040 --> 00:31:02,040
Speaker 1: It's like negative of your right hand. So this is

624
00:31:02,040 --> 00:31:04,200
Speaker 1: the part where we're being like a little bit fuzzy

625
00:31:04,240 --> 00:31:07,880
Speaker 1: and sloppy. But fermions, because they spin one half when

626
00:31:07,920 --> 00:31:10,400
Speaker 1: you swap them, you get a negative sign in the

627
00:31:10,480 --> 00:31:11,160
Speaker 1: quantum state.

628
00:31:11,320 --> 00:31:15,360
Speaker 2: Okay, So that only happens with fermions, not with bosons.

629
00:31:15,560 --> 00:31:19,080
Speaker 1: Only with fermions, not with bosons. And that's what makes

630
00:31:19,120 --> 00:31:22,040
Speaker 1: this impossible. That's where we have a contradiction, right, because

631
00:31:22,720 --> 00:31:25,120
Speaker 1: say you have these two particles in the same state.

632
00:31:25,240 --> 00:31:28,160
Speaker 1: Say you started with one A two A, right, both

633
00:31:28,200 --> 00:31:29,400
Speaker 1: particles in the same state.

634
00:31:29,520 --> 00:31:32,360
Speaker 2: Can't do that, Okay, Oh no, you can with bosons.

635
00:31:32,000 --> 00:31:33,880
Speaker 1: You can with bosons. Well, let's say we have fermions

636
00:31:33,880 --> 00:31:35,720
Speaker 1: and we try to do that. Let's try to do

637
00:31:35,760 --> 00:31:38,040
Speaker 1: that and see what happens. Okay, so we have one

638
00:31:38,080 --> 00:31:40,640
Speaker 1: A two A where like we put two fermions in

639
00:31:40,720 --> 00:31:44,360
Speaker 1: the same place, in the same state. Okay, Well, now

640
00:31:44,400 --> 00:31:47,000
Speaker 1: let's swap them. Well, what happens. Quantum field theory says

641
00:31:47,040 --> 00:31:50,480
Speaker 1: we get negative one A two A. Okay, right, because

642
00:31:50,520 --> 00:31:52,880
Speaker 1: when we swap fermions we get a negative sign. But

643
00:31:52,880 --> 00:31:55,560
Speaker 1: these are supposed to be indistinguishable particles, so if you

644
00:31:55,600 --> 00:31:58,400
Speaker 1: swap them, you shouldn't get any change because there's no

645
00:31:58,440 --> 00:32:00,960
Speaker 1: real difference. You're swapping one A to two you have

646
00:32:01,040 --> 00:32:03,520
Speaker 1: to get one A two A. But quantum field theory says, no,

647
00:32:03,920 --> 00:32:06,640
Speaker 1: you have to get negative one A two A. So

648
00:32:06,680 --> 00:32:09,520
Speaker 1: we have two different rules. One that says if you

649
00:32:09,560 --> 00:32:12,160
Speaker 1: have particles in the same state and they're indistinguishable, and

650
00:32:12,200 --> 00:32:15,680
Speaker 1: you swap them, nothing happens. And the other rule from

651
00:32:15,760 --> 00:32:18,240
Speaker 1: field theory that says if they're fermions and you swap them,

652
00:32:18,320 --> 00:32:22,480
Speaker 1: you get a negative sign. Boom, that's a contradiction. So

653
00:32:22,520 --> 00:32:24,920
Speaker 1: that tells us you just can't do this. You can't

654
00:32:24,960 --> 00:32:27,800
Speaker 1: have fermions in the same state because then if you

655
00:32:27,800 --> 00:32:30,360
Speaker 1: swap them, you get a contradiction. Quantum field theory says

656
00:32:30,400 --> 00:32:33,200
Speaker 1: you're supposed to get a negative sign. Common sense says

657
00:32:33,520 --> 00:32:35,680
Speaker 1: you can't get a negative sign if you swap things

658
00:32:35,680 --> 00:32:36,440
Speaker 1: that aren't different.

659
00:32:36,680 --> 00:32:40,160
Speaker 2: Okay, So the Pauly exclusion principle is the result of

660
00:32:40,240 --> 00:32:41,960
Speaker 2: what happens with quantum field theory.

661
00:32:42,240 --> 00:32:45,320
Speaker 1: Yes, exactly. And you might think, well, what's this negative sign?

662
00:32:45,400 --> 00:32:47,960
Speaker 1: What is going on there? Remember that this negative sign

663
00:32:48,000 --> 00:32:51,720
Speaker 1: is part of the quantum state. It's not something we observe, right,

664
00:32:52,000 --> 00:32:54,240
Speaker 1: a negative sign and a quantum state is not observable

665
00:32:54,240 --> 00:32:56,840
Speaker 1: because every observable you make is only sensitive to the

666
00:32:56,920 --> 00:33:00,520
Speaker 1: quantum states squared. Remember quantum state. It can also be

667
00:33:00,600 --> 00:33:03,080
Speaker 1: like complex numbers. You can have like a wave function

668
00:33:03,160 --> 00:33:05,480
Speaker 1: has like four plus two I in it, and you

669
00:33:05,480 --> 00:33:08,000
Speaker 1: can't observe those things, but when you square it, the

670
00:33:08,040 --> 00:33:11,040
Speaker 1: imaginary part goes away, so we can't observe this. It's

671
00:33:11,080 --> 00:33:13,760
Speaker 1: like a hidden internal part of the quantum state. We

672
00:33:13,800 --> 00:33:16,680
Speaker 1: can't observe. And yet the math is there and it's real,

673
00:33:16,720 --> 00:33:18,960
Speaker 1: and it tells us that fermions cannot do this thing

674
00:33:19,000 --> 00:33:22,800
Speaker 1: because it leads to an inherent contradiction. Now, spin one particles,

675
00:33:22,840 --> 00:33:27,040
Speaker 1: bosons are different. Their rules when you swap them are different.

676
00:33:27,400 --> 00:33:29,640
Speaker 1: If you swap one A two B, and now you're

677
00:33:29,680 --> 00:33:32,680
Speaker 1: talking about bosons, you don't get the negative sign. You

678
00:33:32,800 --> 00:33:36,200
Speaker 1: just get one B two A. Everybody's happy. So if

679
00:33:36,240 --> 00:33:38,480
Speaker 1: you started with one A two A and you swap them,

680
00:33:38,720 --> 00:33:41,000
Speaker 1: quantum field theory says you get one A two A.

681
00:33:41,040 --> 00:33:43,920
Speaker 1: Common sense says you get one A two A, no contradiction.

682
00:33:44,360 --> 00:33:48,440
Speaker 1: Everybody's cool. It's that negative sign, that unobservable negative sign

683
00:33:48,480 --> 00:33:51,440
Speaker 1: in the quantum state that appears for fermions when you

684
00:33:51,480 --> 00:33:54,480
Speaker 1: swap them. That causes them to never be allowed to

685
00:33:54,480 --> 00:33:58,080
Speaker 1: be in the same quantum state if they're indistinguishable fermions.

686
00:33:58,520 --> 00:34:00,480
Speaker 2: Okay, so just to make sure that I'm under so

687
00:34:00,560 --> 00:34:03,440
Speaker 2: like negative one and one, they cancel each other out

688
00:34:03,480 --> 00:34:04,800
Speaker 2: when you add them together.

689
00:34:04,840 --> 00:34:06,560
Speaker 3: Or when you square them you get the same answer.

690
00:34:06,680 --> 00:34:09,759
Speaker 2: Okay, And so I should be keeping that in my head.

691
00:34:09,800 --> 00:34:13,400
Speaker 2: This isn't like we arbitrarily identified that some state is

692
00:34:13,480 --> 00:34:16,520
Speaker 2: negative one, and you could have called the states A, B,

693
00:34:16,680 --> 00:34:20,080
Speaker 2: and C. Like there is actually something about negative one

694
00:34:20,160 --> 00:34:24,680
Speaker 2: and one that is different in an important mathematical.

695
00:34:24,160 --> 00:34:28,040
Speaker 1: Way, exactly. And the important thing here is fermions have

696
00:34:28,120 --> 00:34:30,640
Speaker 1: a different kind of spin, and that changes what happens

697
00:34:30,640 --> 00:34:33,120
Speaker 1: when you swamp them and introduces this negative sign.

698
00:34:33,280 --> 00:34:33,560
Speaker 3: Okay.

699
00:34:33,680 --> 00:34:36,239
Speaker 1: And if you're curious about why that is exactly, this

700
00:34:36,320 --> 00:34:39,560
Speaker 1: is the bit that's famously impossible to explain with intuition.

701
00:34:39,920 --> 00:34:40,920
Speaker 3: We have math for it.

702
00:34:40,920 --> 00:34:43,720
Speaker 1: It's called the spin statistics theorem. And even Richard Meineman

703
00:34:43,800 --> 00:34:46,600
Speaker 1: couldn't come up with an intuitive explanation for it. So

704
00:34:46,680 --> 00:34:48,919
Speaker 1: I hope you're gonna excuse me for not having one either.

705
00:34:49,520 --> 00:34:51,279
Speaker 1: But if you take us out a word for that,

706
00:34:51,320 --> 00:34:53,240
Speaker 1: the fermions, when you swap them, you get a negative

707
00:34:53,280 --> 00:34:56,080
Speaker 1: sign that's not observable, but it does prevent them from

708
00:34:56,120 --> 00:34:58,400
Speaker 1: ever being in the same quantum state. Then you can

709
00:34:58,440 --> 00:35:01,920
Speaker 1: go from there to understand why the Fermi exclusion principle happens.

710
00:35:02,080 --> 00:35:04,640
Speaker 1: And it's going to lead us to think about the

711
00:35:04,680 --> 00:35:08,120
Speaker 1: third way that paraparticles might behave And if.

712
00:35:07,960 --> 00:35:11,080
Speaker 2: You are excited about that, then stick with us, because

713
00:35:11,080 --> 00:35:33,040
Speaker 2: we're gonna get to it after the break. Okay, so

714
00:35:33,360 --> 00:35:36,160
Speaker 2: we teased you before the commercial break that we're going

715
00:35:36,160 --> 00:35:39,360
Speaker 2: to explain to you how para particles behave. Your weight

716
00:35:39,480 --> 00:35:43,360
Speaker 2: is over, Daniel tell us about paraparticles and how they behave.

717
00:35:43,719 --> 00:35:46,920
Speaker 1: So for a long time, decades and decades, people thought

718
00:35:47,239 --> 00:35:51,000
Speaker 1: that fermions and bosons were the only options, not only

719
00:35:51,080 --> 00:35:54,279
Speaker 1: because hey, look, spin one half and integer spins seemed

720
00:35:54,320 --> 00:35:57,239
Speaker 1: like the only choices because like spin one third or

721
00:35:57,239 --> 00:35:59,880
Speaker 1: spin two thirds is impossible, but also in terms of

722
00:35:59,880 --> 00:36:02,319
Speaker 1: the explanation we just gave, it feels like there are

723
00:36:02,320 --> 00:36:04,560
Speaker 1: two options. Either you add a negative sign when you

724
00:36:04,560 --> 00:36:06,920
Speaker 1: swap them, like fermions, which means you can't be in

725
00:36:06,960 --> 00:36:10,359
Speaker 1: the same quantum state, or you don't like bosons, which

726
00:36:10,400 --> 00:36:12,680
Speaker 1: means you can be in the same quantum state. So

727
00:36:12,760 --> 00:36:14,799
Speaker 1: it seems like there's no crack there. It seems like

728
00:36:14,800 --> 00:36:18,120
Speaker 1: there's no room for another direction. And in the nineteen

729
00:36:18,160 --> 00:36:20,400
Speaker 1: seventies somebody went to a bunch of math to prove

730
00:36:21,000 --> 00:36:24,719
Speaker 1: that there is no third option under certain conditions. So

731
00:36:24,760 --> 00:36:27,160
Speaker 1: like if you live in a universe where space has

732
00:36:27,200 --> 00:36:30,160
Speaker 1: three dimensions, then there is no other option. You have

733
00:36:30,200 --> 00:36:32,840
Speaker 1: fermions and you have bosons, and that's its zip and period.

734
00:36:33,239 --> 00:36:35,279
Speaker 1: So people sort of put this away for a long time.

735
00:36:35,280 --> 00:36:38,279
Speaker 1: They were like, yeah, well that's done. Somebody proved it

736
00:36:38,680 --> 00:36:41,040
Speaker 1: dot dot dot. Nobody should ever spend time thinking about

737
00:36:41,080 --> 00:36:43,719
Speaker 1: it again. And that's like a famous place to make

738
00:36:43,760 --> 00:36:47,719
Speaker 1: a big discovery, because I'm sure this happens in biology. Also,

739
00:36:48,360 --> 00:36:51,239
Speaker 1: you have a paper which makes a big advance and

740
00:36:51,280 --> 00:36:54,319
Speaker 1: then it gets sort of summarized in a shorthanded sort

741
00:36:54,320 --> 00:36:57,359
Speaker 1: of way that ignores some of the assumptions that went

742
00:36:57,400 --> 00:36:59,920
Speaker 1: into it, and the conclusions just sort of get broaden

743
00:37:00,160 --> 00:37:02,160
Speaker 1: a little bit, and then people treat the lore as

744
00:37:02,200 --> 00:37:05,239
Speaker 1: if it was real and complete, and people rarely go

745
00:37:05,280 --> 00:37:07,920
Speaker 1: back and read the original paper to discover ooh, actually

746
00:37:08,000 --> 00:37:11,200
Speaker 1: there are coveyats here. So there are loopholes, and people

747
00:37:11,239 --> 00:37:13,759
Speaker 1: who do and discover those loopholes and then explore them

748
00:37:14,080 --> 00:37:17,200
Speaker 1: can like crack open a whole new area of physics.

749
00:37:17,200 --> 00:37:17,680
Speaker 3: Sometimes.

750
00:37:17,760 --> 00:37:19,799
Speaker 2: That's why it is so critical to read and to

751
00:37:19,880 --> 00:37:21,160
Speaker 2: read the original papers.

752
00:37:21,440 --> 00:37:23,320
Speaker 1: And for those of you wondering what that sound is

753
00:37:23,320 --> 00:37:26,680
Speaker 1: in the background. That's a big rainstorm in Virginia right now.

754
00:37:27,120 --> 00:37:30,200
Speaker 2: I love rain. Was that a dig on Virginia?

755
00:37:30,520 --> 00:37:32,560
Speaker 3: Why do you assume that's a dig? That's definitely not

756
00:37:32,640 --> 00:37:33,000
Speaker 3: a dig.

757
00:37:33,320 --> 00:37:34,360
Speaker 2: This is because I know you.

758
00:37:36,000 --> 00:37:38,680
Speaker 1: This week I'm an Aspen for the Aspen Center for Physics,

759
00:37:39,120 --> 00:37:41,759
Speaker 1: and it rains every afternoon and I love it. The

760
00:37:41,800 --> 00:37:45,200
Speaker 1: smell of it in the mountains is just wonderful. The

761
00:37:45,280 --> 00:37:47,200
Speaker 1: thing I do love about mountain rain is that it

762
00:37:47,360 --> 00:37:48,600
Speaker 1: ends also quickly.

763
00:37:48,800 --> 00:37:51,719
Speaker 2: Yeah, well, well those are rainstorms don't last very long.

764
00:37:52,360 --> 00:37:54,040
Speaker 2: And I am the reason you can hear it is

765
00:37:54,040 --> 00:37:57,400
Speaker 2: because I converted the tech room in the barn, the

766
00:37:57,440 --> 00:38:00,840
Speaker 2: horse barn that we have on our property to my office,

767
00:38:00,960 --> 00:38:03,000
Speaker 2: and so there's a metal roof above me, and so

768
00:38:03,080 --> 00:38:06,839
Speaker 2: the metal roof really makes the sound of rain much louder,

769
00:38:06,880 --> 00:38:09,080
Speaker 2: which I love when I'm sleeping up here at night.

770
00:38:09,120 --> 00:38:10,759
Speaker 2: Every once in a while I have sleepovers up here

771
00:38:10,800 --> 00:38:13,520
Speaker 2: with my daughter on Friday nights. But anyway, sorry about

772
00:38:13,520 --> 00:38:15,760
Speaker 2: the background noise, everyone, no problem.

773
00:38:16,080 --> 00:38:19,600
Speaker 1: And we now have enough background to understand paraparticles because

774
00:38:19,719 --> 00:38:23,879
Speaker 1: very recently two physicists at Rice University, which we both

775
00:38:23,960 --> 00:38:28,320
Speaker 1: know and love found some loopholes in this nineteen seventies

776
00:38:28,480 --> 00:38:31,200
Speaker 1: no go theorem, the one the famously said it's impossible

777
00:38:31,200 --> 00:38:34,239
Speaker 1: to have anything but a fermion and a boson. And

778
00:38:34,280 --> 00:38:37,239
Speaker 1: the loophole is, what if you give these particles some

779
00:38:37,440 --> 00:38:41,080
Speaker 1: other kind of properties, things that like a minus sign,

780
00:38:41,480 --> 00:38:46,239
Speaker 1: are not observable directly and disappear when you square it right.

781
00:38:46,280 --> 00:38:48,200
Speaker 1: So like a minus sign is a great example, because

782
00:38:48,239 --> 00:38:50,400
Speaker 1: you square it, you have plus one. If you didn't

783
00:38:50,400 --> 00:38:52,960
Speaker 1: have a minus sign, you can't tell plus one squared

784
00:38:53,000 --> 00:38:55,719
Speaker 1: and minus one squared have the same answer. But they

785
00:38:55,760 --> 00:38:58,400
Speaker 1: came up with another thing you can add to this particle,

786
00:38:58,480 --> 00:39:01,600
Speaker 1: like another category, another part of the description, not a

787
00:39:01,640 --> 00:39:05,600
Speaker 1: minus sign, but like a new dimension to this quantum field,

788
00:39:06,040 --> 00:39:08,279
Speaker 1: a new attribute, a new label you can give it,

789
00:39:08,840 --> 00:39:12,000
Speaker 1: and this kind of thing. Also when you square it,

790
00:39:12,000 --> 00:39:15,279
Speaker 1: it goes away. So there's some technical details here, but

791
00:39:15,320 --> 00:39:18,200
Speaker 1: the sort of way to understand it intuitively is that

792
00:39:18,280 --> 00:39:22,120
Speaker 1: these internal states depend on the observer a little bit.

793
00:39:22,560 --> 00:39:27,040
Speaker 1: So like you and I might see this electron differently

794
00:39:27,520 --> 00:39:30,800
Speaker 1: because we're different observers and we might make different observations.

795
00:39:31,040 --> 00:39:33,839
Speaker 3: So it's a little bit of like relativity there. So

796
00:39:33,880 --> 00:39:34,200
Speaker 3: if you.

797
00:39:34,200 --> 00:39:37,640
Speaker 1: Add this to some particle states in a weird mathematical way,

798
00:39:38,320 --> 00:39:41,759
Speaker 1: you can create a new kind of behavior. So it

799
00:39:41,880 --> 00:39:44,160
Speaker 1: sort of like fuzzes up a little bit, this notion

800
00:39:44,200 --> 00:39:48,640
Speaker 1: of indistinguishable particles. Are the particles indistinguishable or not? So

801
00:39:48,680 --> 00:39:51,360
Speaker 1: you might be wondering, well, we have electrons and we

802
00:39:51,440 --> 00:39:54,480
Speaker 1: have photons. Are there things out there in the universe

803
00:39:54,520 --> 00:39:57,920
Speaker 1: that follow this new weird quantum math. The answer is,

804
00:39:58,239 --> 00:40:02,280
Speaker 1: we don't know, not yet. What they've done is show

805
00:40:02,360 --> 00:40:07,160
Speaker 1: that there is another mathematical description of fields and particles

806
00:40:07,160 --> 00:40:10,239
Speaker 1: that you can construct that has like a third kind

807
00:40:10,239 --> 00:40:13,360
Speaker 1: of behavior. It's not a fermion and it's not a boson,

808
00:40:13,960 --> 00:40:18,480
Speaker 1: but it is self consistent and mathematical. Nobody's built one,

809
00:40:18,680 --> 00:40:21,799
Speaker 1: but they just sort of like mathematically shown that as

810
00:40:21,840 --> 00:40:24,200
Speaker 1: far as we know, the rules of the universe don't

811
00:40:24,200 --> 00:40:24,960
Speaker 1: disallow this.

812
00:40:25,400 --> 00:40:28,680
Speaker 2: So I don't want to ever question the amazing research

813
00:40:28,680 --> 00:40:31,760
Speaker 2: that comes out of Rice University. But it sounds like okay,

814
00:40:31,760 --> 00:40:33,400
Speaker 2: So they're like, well, there's this one thing we can't

815
00:40:33,440 --> 00:40:37,520
Speaker 2: see and can't measure, and so let's add another thing

816
00:40:37,560 --> 00:40:39,799
Speaker 2: we can't see or we can't measure. It's just like fire,

817
00:40:40,000 --> 00:40:41,799
Speaker 2: you know, like biologists can't be like, well, what if

818
00:40:41,800 --> 00:40:45,440
Speaker 2: the viruses we're wearing hats, maybe we should look for

819
00:40:46,719 --> 00:40:49,520
Speaker 2: what's a good combination of hat and viruses?

820
00:40:49,800 --> 00:40:50,000
Speaker 3: Right.

821
00:40:50,239 --> 00:40:52,439
Speaker 1: This is like taking the quantum particles and saying, hey,

822
00:40:52,760 --> 00:40:55,279
Speaker 1: we've only been thinking about them wearing cowboy hats.

823
00:40:55,280 --> 00:40:56,760
Speaker 3: What if they wear other kinds of hats?

824
00:40:56,920 --> 00:40:59,200
Speaker 1: What if choice of hats is another like degree of

825
00:40:59,239 --> 00:41:03,160
Speaker 1: freedom for describing these particles. And it turns out if

826
00:41:03,160 --> 00:41:05,520
Speaker 1: you do that, it cracks this open a little bit

827
00:41:05,560 --> 00:41:07,759
Speaker 1: and it lets you have another category. And so that's

828
00:41:07,800 --> 00:41:12,840
Speaker 1: interesting mathematically. It's only interesting physically if it describes the universe.

829
00:41:12,880 --> 00:41:15,000
Speaker 1: If the universe does this in the same way that

830
00:41:15,080 --> 00:41:18,680
Speaker 1: like DrAk looked at the solutions to the Shortener equation

831
00:41:18,760 --> 00:41:21,160
Speaker 1: and he was like, oh, this is interesting. This allows

832
00:41:21,200 --> 00:41:23,799
Speaker 1: you to have electrons but also allows you to have

833
00:41:23,960 --> 00:41:28,160
Speaker 1: positively charged particles. That doesn't mean the universe does it, right.

834
00:41:28,520 --> 00:41:31,120
Speaker 1: It could have just been like a mathematical oddity like, oh,

835
00:41:31,200 --> 00:41:33,799
Speaker 1: the math allows this, but does the universe choose it?

836
00:41:33,840 --> 00:41:36,680
Speaker 1: And turns out yes, the universe does choose to make antiparticles,

837
00:41:37,080 --> 00:41:40,960
Speaker 1: and the universe in many other cases chooses to explore

838
00:41:41,120 --> 00:41:44,040
Speaker 1: all the avenues of symmetries. We don't know if it does.

839
00:41:44,080 --> 00:41:44,680
Speaker 3: In this case.

840
00:41:45,080 --> 00:41:48,000
Speaker 1: What we've shown is that the mathematics of our description

841
00:41:48,120 --> 00:41:52,040
Speaker 1: of the universe do allow for our third category particles paraparticles,

842
00:41:52,520 --> 00:41:54,799
Speaker 1: but we don't know if they do ever exist in

843
00:41:54,840 --> 00:41:57,640
Speaker 1: the universe, and if they do, we don't think they

844
00:41:57,640 --> 00:42:01,520
Speaker 1: would be fundamental particles the way like photons and electrons are,

845
00:42:01,560 --> 00:42:04,600
Speaker 1: because there are no fundamental particles we know of that

846
00:42:04,680 --> 00:42:07,560
Speaker 1: fall into this category. You'd have to make like quasi

847
00:42:07,600 --> 00:42:12,480
Speaker 1: particles the way you make like anions or plasmons or phonons.

848
00:42:12,960 --> 00:42:16,480
Speaker 1: These are things that follow the math of particles. But

849
00:42:16,719 --> 00:42:20,520
Speaker 1: our waves not in a fundamental field like the electromagnetic

850
00:42:20,520 --> 00:42:23,360
Speaker 1: field or the electron field, but a wave in something else,

851
00:42:23,600 --> 00:42:25,560
Speaker 1: like a wave in air, or a wave in water,

852
00:42:26,160 --> 00:42:30,000
Speaker 1: or a wave in electron gas in some weird meta

853
00:42:30,040 --> 00:42:33,000
Speaker 1: material that solid state physicists cook up in their dark

854
00:42:33,040 --> 00:42:36,600
Speaker 1: little labs. And so it might be something that people

855
00:42:36,680 --> 00:42:39,680
Speaker 1: can create in the labs someday in the future and show, oh, look,

856
00:42:39,960 --> 00:42:43,640
Speaker 1: we've created this new quasi particle that has a different

857
00:42:43,680 --> 00:42:47,640
Speaker 1: kind of mathematical behavior than fermions or bosons. So that

858
00:42:47,640 --> 00:42:50,440
Speaker 1: would be cool and something nobody had seen before. Doesn't

859
00:42:50,480 --> 00:42:53,440
Speaker 1: mean we can make hoverboards or we can make wormholes

860
00:42:53,560 --> 00:42:56,319
Speaker 1: or anything like that yet, But you never know with

861
00:42:56,360 --> 00:42:58,440
Speaker 1: fundamental physics, like what's this going to lead to?

862
00:42:58,920 --> 00:42:59,640
Speaker 3: It's very deep.

863
00:42:59,600 --> 00:43:02,480
Speaker 1: It's very much at the foundation of quantum field theory

864
00:43:02,480 --> 00:43:04,920
Speaker 1: and our understanding of like the mathematics of it. So

865
00:43:04,960 --> 00:43:08,400
Speaker 1: it's exciting when anybody makes any progress in that area.

866
00:43:08,520 --> 00:43:10,520
Speaker 1: And it's a great example to push back on the

867
00:43:10,560 --> 00:43:13,120
Speaker 1: nonsense you might hear online that like physics hasn't made

868
00:43:13,160 --> 00:43:16,359
Speaker 1: any progress since the nineteen seventies. Like, dude, we're making

869
00:43:16,360 --> 00:43:18,640
Speaker 1: progress all the time. And here's a great example.

870
00:43:19,160 --> 00:43:21,719
Speaker 2: So are people currently working on experiments to try to

871
00:43:21,760 --> 00:43:22,880
Speaker 2: find these particles?

872
00:43:23,280 --> 00:43:28,680
Speaker 3: Yeah, more create than find. People are trying to engineer weird.

873
00:43:28,480 --> 00:43:31,920
Speaker 1: Exotic materials that might have these behaviors. And this is

874
00:43:31,960 --> 00:43:34,120
Speaker 1: the kind of stuff solid state physicists love to do,

875
00:43:34,280 --> 00:43:36,480
Speaker 1: you know. They're like, what if we made super thin

876
00:43:36,600 --> 00:43:39,640
Speaker 1: layers of graphene and then super thin layers of this,

877
00:43:40,000 --> 00:43:42,920
Speaker 1: and could we force the electrons to act as if

878
00:43:42,920 --> 00:43:45,640
Speaker 1: they're in a two D universe? Or can we see

879
00:43:45,760 --> 00:43:51,080
Speaker 1: superconductivity or whatever. So they're very clever at engineering materials

880
00:43:51,440 --> 00:43:54,160
Speaker 1: to make quantum states behave in new ways, and that's

881
00:43:54,400 --> 00:43:57,480
Speaker 1: the most promising way. We might see something that's a paraparticle,

882
00:43:57,800 --> 00:44:00,840
Speaker 1: you would be an emergent phenomenon, a quad particle that

883
00:44:00,960 --> 00:44:05,919
Speaker 1: comes out of the behavior of these weird exotic systems

884
00:44:06,400 --> 00:44:10,239
Speaker 1: and not exotic and like impossible or wrong in any way,

885
00:44:10,440 --> 00:44:13,600
Speaker 1: just like not something we find in nature usually. But

886
00:44:13,640 --> 00:44:16,080
Speaker 1: that's the cool thing about being humans. We're like constantly

887
00:44:16,480 --> 00:44:18,799
Speaker 1: pushing the boundaries and saying, hey, can the universe do this?

888
00:44:18,880 --> 00:44:21,400
Speaker 1: What happens if we do that? And it teaches us

889
00:44:21,440 --> 00:44:23,560
Speaker 1: things about the universe. This is how we learn where

890
00:44:23,600 --> 00:44:26,000
Speaker 1: the boundaries are by pushing them, right, yeah.

891
00:44:26,080 --> 00:44:28,120
Speaker 2: Yeah, So when we have a guest on our show,

892
00:44:28,680 --> 00:44:32,200
Speaker 2: you usually end the interview by asking them if an

893
00:44:32,239 --> 00:44:35,879
Speaker 2: alien were to visit our planets from an advanced civilization,

894
00:44:36,600 --> 00:44:39,080
Speaker 2: and you ask them if their thing exists on their

895
00:44:39,080 --> 00:44:41,879
Speaker 2: home planets. That's your way of testing how confident they

896
00:44:41,880 --> 00:44:45,320
Speaker 2: are that the thing actually exists. So, Daniel, if aliens

897
00:44:45,360 --> 00:44:48,040
Speaker 2: from an advanced civilization landed on Earth, do you think

898
00:44:48,120 --> 00:44:51,960
Speaker 2: they would know about paraparticles and would think that paraparticles existed?

899
00:44:52,400 --> 00:44:54,359
Speaker 1: This is a great question and a fair one, since

900
00:44:54,360 --> 00:44:56,799
Speaker 1: I just wrote a whole book on how aliens might

901
00:44:56,840 --> 00:44:59,040
Speaker 1: think about the universe. Y'all should check it out. It's

902
00:44:59,040 --> 00:45:02,120
Speaker 1: coming out in November. It's called Do Aliens Speak Physics.

903
00:45:02,560 --> 00:45:03,799
Speaker 1: I'm really excited about it.

904
00:45:03,840 --> 00:45:04,919
Speaker 2: Two sums way up.

905
00:45:05,160 --> 00:45:10,400
Speaker 1: My personal suspicion is that particle physicists are too up

906
00:45:10,480 --> 00:45:12,919
Speaker 1: in their own heads and they think that the whole

907
00:45:13,040 --> 00:45:17,279
Speaker 1: universe uses their mathematical description of how things work. And

908
00:45:17,320 --> 00:45:20,640
Speaker 1: that's just like too self centered to put ourselves at

909
00:45:20,680 --> 00:45:24,280
Speaker 1: the heart of the understanding of the universe. And likely

910
00:45:24,360 --> 00:45:27,200
Speaker 1: there's a bunch of arbitrary assumptions we've made, and probably

911
00:45:27,280 --> 00:45:30,600
Speaker 1: aliens have a completely different description of how the universe works,

912
00:45:30,840 --> 00:45:33,720
Speaker 1: and they're like, what, why are we even using quantum fields?

913
00:45:33,760 --> 00:45:36,520
Speaker 1: That makes no sense. Here's a much simpler way. But

914
00:45:36,920 --> 00:45:39,560
Speaker 1: if they are using quantum fields, then I think this

915
00:45:39,600 --> 00:45:41,520
Speaker 1: is an inevitable discovery.

916
00:45:41,000 --> 00:45:41,480
Speaker 3: They would make.

917
00:45:41,480 --> 00:45:43,680
Speaker 1: And they might have even found other ways, like there

918
00:45:43,719 --> 00:45:46,880
Speaker 1: might be four, seventeen or ninety two different kinds of

919
00:45:46,880 --> 00:45:49,680
Speaker 1: particles and they're like, what y'all have only found three?

920
00:45:49,840 --> 00:45:51,960
Speaker 1: Come back to us. You can join the cosmic society

921
00:45:51,960 --> 00:45:52,759
Speaker 1: when you're up to ten.

922
00:45:53,000 --> 00:45:58,040
Speaker 2: When you found particles, Then if they talk to us exactly.

923
00:45:59,000 --> 00:46:01,760
Speaker 1: Yeah, and maybe they'll listen this podcast and ooh, particles

924
00:46:01,760 --> 00:46:02,360
Speaker 1: and parasites.

925
00:46:02,360 --> 00:46:03,759
Speaker 3: Maybe these guys are on the right track.

926
00:46:03,920 --> 00:46:06,840
Speaker 2: Oh my gosh. Yeah, at least they'll think that we're interesting.

927
00:46:07,480 --> 00:46:10,160
Speaker 1: Aliens, if you are listening, please don't zap ups from

928
00:46:10,160 --> 00:46:10,720
Speaker 1: outer space.

929
00:46:10,840 --> 00:46:12,920
Speaker 2: Come talk to us, tell us about your secrets, and

930
00:46:12,920 --> 00:46:15,480
Speaker 2: tell us about your parasites, but keep it to yourselves,

931
00:46:17,719 --> 00:46:18,080
Speaker 2: all right.

932
00:46:18,120 --> 00:46:20,799
Speaker 1: Thanks everyone for going on this journey with us into

933
00:46:20,800 --> 00:46:23,200
Speaker 1: the heart of particle physics, how it works, what we know,

934
00:46:23,280 --> 00:46:26,040
Speaker 1: what we don't know, and the hints that mathematics is

935
00:46:26,040 --> 00:46:28,880
Speaker 1: giving us about what we might learn about the fundamental

936
00:46:28,960 --> 00:46:33,000
Speaker 1: nature of space and time and matter and energy and aliens.

937
00:46:33,320 --> 00:46:43,400
Speaker 2: See y'all next time. Daniel and Kelly's Extraordinary Universe is

938
00:46:43,440 --> 00:46:46,480
Speaker 2: produced by iHeartRadio. We would love to hear from you,

939
00:46:46,719 --> 00:46:47,800
Speaker 2: We really would.

940
00:46:47,880 --> 00:46:50,640
Speaker 1: We want to know what questions you have about this

941
00:46:50,840 --> 00:46:52,480
Speaker 1: Extraordinary Universe.

942
00:46:52,600 --> 00:46:55,520
Speaker 2: We want to know your thoughts on recent shows, suggestions

943
00:46:55,560 --> 00:46:58,560
Speaker 2: for future shows. If you contact us, we will get

944
00:46:58,600 --> 00:46:59,000
Speaker 2: back to you.

945
00:46:59,239 --> 00:47:03,000
Speaker 1: We really mean we answer every message. Email us at

946
00:47:03,080 --> 00:47:05,960
Speaker 1: questions at Danielankelly.

947
00:47:05,080 --> 00:47:07,160
Speaker 2: Dot org, or you can find us on social media.

948
00:47:07,280 --> 00:47:11,080
Speaker 2: We have accounts on x, Instagram, Blue Sky, and on

949
00:47:11,160 --> 00:47:13,120
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950
00:47:13,560 --> 00:47:15,040
Speaker 2: and K Universe.

951
00:47:15,280 --> 00:47:16,839
Speaker 3: Don't be shy, write to us,