Speaker 1: What's the point of building bigger and bigger colliders other
Speaker 1: than the obvious fun and awesomeness of it all. It's
Speaker 1: a machine that opens up the sub atomic world. It's
Speaker 1: not just because we like to see things go boom,
Speaker 1: though of course we do, but because we want to
Speaker 1: know what happens when you pull things apart. What's inside me,
Speaker 1: what's inside you, what's inside everything. At the root of
Speaker 1: it all is a desire to dig as deep as
Speaker 1: we can into the very nature of matter, to hope
Speaker 1: to reveal its inner workings and understand how it all
Speaker 1: comes together to make our amazing, crazy and delicious world.
Speaker 1: Is the universe made of quarks and leptons and dark matter?
Speaker 1: Or is it made of strings or shmings or bada bings?
Speaker 1: Right now we don't know. We might never know, or
Speaker 1: one day and we might build a collider powerful enough
Speaker 1: to show us the universe's fundamental lego bricks. Then we
Speaker 1: can turned to the philosophers and ask them, hey, so
Speaker 1: what does this mean? Dude? But what if we don't
Speaker 1: get the billions to build a bigger collider? Is that
Speaker 1: the only way forward? Can we find some other clever
Speaker 1: way to get this information through the universe's back door.
Speaker 1: That's what we're going to talk about on today's episode.
Speaker 1: Welcome to Daniel and Kelly's Extraordinary Universe, brought to you
Speaker 1: by all the tiny particles that make it possible.
Speaker 2: Hello. I'm Kelly leader Smith. I'm a parasitologist who also
Speaker 2: studies space, and I'm wondering if today we're going to
Speaker 2: be talking about something that Daniel studies staring his day job.
Speaker 1: Hi. I'm Daniel. I'm a particle physicist and my job
Speaker 1: is to play with taxpayer funded billion dollar toys.
Speaker 2: Ooh, my job usually involves playing with fish bomb and
Speaker 2: I think your job might be better.
Speaker 1: I hope nobody I've ever paid a billion dollars for
Speaker 1: fish vomit.
Speaker 2: There are some important questions that can get answered with
Speaker 2: a lot of fish vomit. But yeah, probably not a
Speaker 2: billion dollars worth. I'll give you that. Maybe a million
Speaker 2: dollars worth. So you work at the LAC and we're
Speaker 2: going to be talking about research happening at the LAC.
Speaker 2: Is the thing that we're talking about today? Is this
Speaker 2: a question that you were working on or what does
Speaker 2: your lab do exactly? Daniel?
Speaker 1: Mostly I take naps, in my office. Isn't that enough?
Speaker 2: Yeah, I'm sure everyone feels great about where their taxpayer
Speaker 2: dollars are going right now.
Speaker 1: Yeah, it's a fair question. What is Daniel actually do
Speaker 1: all day? We should have a whole episode where I
Speaker 1: talk about my research, But very briefly, in the last
Speaker 1: ten years or so, I was looking for dark matter
Speaker 1: at the Large Hadron Collider, smashing particles together, hoping to
Speaker 1: make dark matter particles which would leave an invisible signature
Speaker 1: which is really hard to pick out, and using machine
Speaker 1: learning to try to filter those patterns out from all
Speaker 1: of the noise, which is a fun challenge. But then
Speaker 1: dark matter sort of became too popular at the Large
Speaker 1: Hadron Collider and everybody was doing it, and there wasn't
Speaker 1: a whole lot of opportunity to like do new clever stuff.
Speaker 1: So more recently I've pivoted to looking for weird, unexpected stuff. Like,
Speaker 1: we know that dark matter is out there, we should
Speaker 1: be able to see at the collider, so let's go
Speaker 1: look for it. That makes sense. But what would be
Speaker 1: even more exciting to me is to find something that
Speaker 1: nobody expected, a discovery that makes people go, what, that's impossible,
Speaker 1: or that's crazy or huh, how could that even be
Speaker 1: something that nobody expected? And that's hard to do because
Speaker 1: you sort of have to have an idea for what
Speaker 1: you're looking for in order to go looking for it.
Speaker 1: But we use some cool machine learning tools, anomaly detection
Speaker 1: and all sorts of other algorithms to try to make
Speaker 1: mathematical what we're looking for, what we're not looking for,
Speaker 1: and to figure out clever ways to look for it.
Speaker 1: So that's one of the things that I'm focusing on
Speaker 1: more recently, is looking for anomalies.
Speaker 2: It's always so interesting to me the way the questions
Speaker 2: that we ask are influenced by things like, well, what
Speaker 2: are other people asking? And too many people are asking this,
Speaker 2: and so I'm going to move on to something else.
Speaker 2: And there's a lot of like social and funding things
Speaker 2: that go into the decision about what to study. I
Speaker 2: guess it makes sense. We're all humans doing work.
Speaker 1: Yeah, there's definitely a lot of that. But I think
Speaker 1: people also underestimate how personal science is. Like people ask
Speaker 1: questions because those are their personal questions, and we all
Speaker 1: benefit from that, like the fact that some people are
Speaker 1: weirdly into fish guts, you know, we learn cool stuff
Speaker 1: about the universe. Because of that, and because some people
Speaker 1: want to stay up late looking into telescopes or get
Speaker 1: their socks wet in the rainforest counting spiders. Because different
Speaker 1: people enjoy different kinds of activities and have different questions,
Speaker 1: we get to learn about all lots of different kinds
Speaker 1: of science. And so you know, there's no like magic
Speaker 1: sorting hat that tells people what science to do. They
Speaker 1: just follow their instincts and also, you know, look for
Speaker 1: opportunities for sure. But I think it really reflects the
Speaker 1: sort of breadth of human curiosity, all the different kinds
Speaker 1: of science that we have, and I think that's all
Speaker 1: wonderful and delicious.
Speaker 2: I absolutely agree limitless human curiosity. You can be interested
Speaker 2: in fish, vomits, leeches, or dark matter or anything in between,
Speaker 2: and even chemistry.
Speaker 1: Don't go that far. You know, I was going to
Speaker 1: say dark matter fish vomit, Like maybe dark fish's vomit
Speaker 1: up dark matter vomit. That would be pretty awesome. That
Speaker 1: would be like where our research overlaps.
Speaker 2: Oh my gosh. Yes, I hope somebody will fund the
Speaker 2: intersection of our research interests. Let's write to the NSF
Speaker 2: and find out.
Speaker 1: But more broadly, There's something really cool about the Large
Speaker 1: A Drunk Collider, which is that it lets you do
Speaker 1: lots of different kinds of things. People have the idea
Speaker 1: that the Large A Drunk Collider is like an experiment
Speaker 1: that I do and then somebody else get the turn
Speaker 1: they do an experiment. In reality, it's the same experiment.
Speaker 1: It's just running twenty four to seven collecting very very
Speaker 1: general data, and people can ask different kinds of questions
Speaker 1: about it. People can be like, hey, dude, we find
Speaker 1: a new particle. People can be like, hey, are the
Speaker 1: particles we've seen do they behave the way we expected?
Speaker 1: Or also like is is there anything weird in the data?
Speaker 1: You can ask all these different kinds of questions with
Speaker 1: the same data from the same setup, and so it's
Speaker 1: very general and very powerful in that way, which I
Speaker 1: love because it lets you pivot easily from different kinds
Speaker 1: of questions.
Speaker 2: So, what is the experiment that's constantly running in the LHC.
Speaker 2: And I'm always going to call it Hadron and embarrass myself.
Speaker 2: So I'm just going to call it the LHC to
Speaker 2: avoid that.
Speaker 1: What's embarrassing about saying Hadron is it because it's so
Speaker 1: close to another word you're afraid of saying.
Speaker 2: Yeah it is.
Speaker 1: That's not family friendly.
Speaker 2: You called out Wienersmith.
Speaker 1: It's true, the large Wienersmith collider. Yeah, what is the experiment? Essentially,
Speaker 1: it's just a big camera around a collision point. You
Speaker 1: smash particles together, and then you try to capture all
Speaker 1: the debris that comes out to get it's much information
Speaker 1: about the collision and the aftermath, so you can piece
Speaker 1: together what happened because you can't see the actual collision directly,
Speaker 1: Like when the quarks annihilate, you don't get to see
Speaker 1: that happen. You just get to see what they turn into.
Speaker 1: So we have these layers of detectors around the collision
Speaker 1: point to take information about those particles so we can
Speaker 1: reconstruct their trajectories and their energies and their angles and
Speaker 1: all sorts of stuff and figure out what happened. And
Speaker 1: we just do that for every collision, no matter what.
Speaker 2: And is it like today we're just running electrons through there,
Speaker 2: or it's like whatever particles happen to be in there
Speaker 2: we're going to run into, or you know, is there
Speaker 2: like a certain combination. What do you start with?
Speaker 1: Yeah, we just go outside and take a scoop of stuff,
Speaker 1: toss it in the collider and see what happened.
Speaker 2: It's like, oh my gosh, you're like biologists.
Speaker 1: We're colliding fish bombit today. No, the collider is very
Speaker 1: sensitive and very carefully tuned, so you have to put
Speaker 1: the right stuff in and tune it. Most of the
Speaker 1: time it runs protons, and so you just start from hydrogen.
Speaker 1: You kick off the electrons, you give them energy, and
Speaker 1: you separate them using their charges. You have pure protons
Speaker 1: and you collide those. The previous collider I worked at
Speaker 1: in Chicago, the Tepatron, collided protons and anti protons, so
Speaker 1: you have to make a source of anti protons a
Speaker 1: whole other factory. That was too complicated. So for the
Speaker 1: next collider, the Large Hadron Collider is just protons and protons,
Speaker 1: but sometimes we do other stuff. Sometimes we put lead
Speaker 1: in there or gold atoms and smash them together because
Speaker 1: you can ask all sorts of interesting questions when you
Speaker 1: have like zillions of protons smashing together. It's called heavy
Speaker 1: ion physics. So yeah, the Large Adron collider is pretty flexible.
Speaker 1: You can collide other kinds of stuff, not just protons,
Speaker 1: probably not fish guts though.
Speaker 2: That's disappointing, but I guess we'll keep talking about physics anyway.
Speaker 2: And so is it like you know, Fridays or the
Speaker 2: gold days, or just somebody like gets a grant and
Speaker 2: that's the day you do the gold ions or whatever instead.
Speaker 1: No, it's like ninety five percent protons. That's the main physics.
Speaker 1: And then occasionally we'll do a run with gold or
Speaker 1: with lead or something else, but it's mostly just proton
Speaker 1: proton physics. That's the bread and butter. The large Adron collider,
Speaker 1: and it's decided some very high level of committees ascerned.
Speaker 1: It is like a collection of dozens of countries, and
Speaker 1: so everything's decided by committees that take forever, and so
Speaker 1: it's very bureaucratic. Even the way we publish a paper
Speaker 1: is very bureaucratic. We have five thousand authors on a
Speaker 1: paper and everybody gets to read it and comment on it.
Speaker 1: So you know, you put a paper through and somebody's
Speaker 1: like add a comma, and somebody else is like remove
Speaker 1: that comments. We also know add that comment, put that comments.
Speaker 1: It's very slow and frustrating, but it's also wonderful to
Speaker 1: work with people from all over the world.
Speaker 2: You have a very nuanced viewpoint on it. That's great.
Speaker 2: I do get frustrated by those bureaucracy, like who cares
Speaker 2: about the comma, Let's just get the paper done. But
Speaker 2: on the other hand, I'm sure you get lots of
Speaker 2: great ideas you wouldn't have gotten otherwise and it was
Speaker 2: just two people working together on the paper.
Speaker 1: Yeah, but the particle collider is very powerful and it
Speaker 1: lets you do things like look for new kind of
Speaker 1: particles directly. But also I think this underappreciated, is that
Speaker 1: there are indirect ways to discover new particles without actually
Speaker 1: seeing them. And that's the thing I want to talk
Speaker 1: about today. How we can use that potentially to see
Speaker 1: inside particles, to learn about what's going on inside the
Speaker 1: particles we think might be fundamental.
Speaker 2: All right, well, and today we're going to be talking
Speaker 2: about how can we see what's inside the electron? And
Speaker 2: we asked our amazing listeners, who are always insightful, to
Speaker 2: tell us what they think the answer is to how
Speaker 2: can we see inside an electron? So let's go ahead
Speaker 2: and hear. What they had to say is that in order.
Speaker 1: To see things at that scale, we would need a
Speaker 1: solar system sized particle collider. If we wanted to try
Speaker 1: to see inside of it, we'd probably have to smash
Speaker 1: other particles into it, and we just have to smash
Speaker 1: them together block we do everything else. To see inside
Speaker 1: an electron, we would need to probe it with something
Speaker 1: that has a wavelength that's smaller than the electron.
Speaker 3: I thought that we couldn't. I thought electrons a fundamental
Speaker 3: and there's nothing in there.
Speaker 1: Because we could crash them together with high energy particle physics,
Speaker 1: can we actually see inside of an electrons? You can't
Speaker 1: smash electrons together, so maybe you do it with neutrinos.
Speaker 2: We might only be able just to look at the
Speaker 2: outside of it, and there might not be anything different
Speaker 2: on the inside.
Speaker 1: I think that electrons are fundamental particles.
Speaker 3: By colliding it with other electrons or other particles and
Speaker 3: seeing what comes.
Speaker 2: Out, it's various quantum states. When probed multiple times with
Speaker 2: perhaps light, will generate some sort of semblance of a structure.
Speaker 1: With a very powerful microscope and a lot of imagination,
Speaker 1: get some pliers and a set of thirty weight ball bearings.
Speaker 1: It's all about ball bearings nowadays.
Speaker 3: Okay, I'm pretty certain Daniel's job is smashing particles together
Speaker 3: and seeing their guts when they pop out. So that's
Speaker 3: my guess. Or maybe the answer is math, but that's
Speaker 3: not nearly as exciting.
Speaker 1: I'm imagining something like X ray crystallography, like Rosalind Franklin
Speaker 1: saw the structure of DNA, but much much more sensitive.
Speaker 1: I mean electron microscope. It's right there in the name.
Speaker 2: Wait wait wait wait wait, I see where this is going.
Speaker 3: Are you asking for more funds to build an even
Speaker 3: larger particle collider?
Speaker 1: As far as I know, there's not an insight of
Speaker 1: the electron to see.
Speaker 4: You like collide electrons together and when they hit each other,
Speaker 4: they like four minutees a big explosion, like a big
Speaker 4: like a big electronic explosion, and when and when that happens,
Speaker 4: it will there's like a giant microscope over it, and
Speaker 4: there's like somebody looking through the microscope and they like
Speaker 4: see what comes out of the explosion.
Speaker 1: M magnets. Thanks to everybody who's sent in these answers.
Speaker 1: If you would like to play for future episodes, don't
Speaker 1: be shy. Write to us two questions at Danielandkelly dot org.
Speaker 1: We want to hear from you and we want your
Speaker 1: voice on the podcast. I love that so many people
Speaker 1: said smash them together. These are particle physicists and folks
Speaker 1: after my heart.
Speaker 2: They've been listening to you. I think they've been listening
Speaker 2: to the show for a while. I like the one
Speaker 2: person who said it involves ball. I think a lot
Speaker 2: of really great scientific questions involve ball bearings. That was
Speaker 2: a good guess.
Speaker 1: If you don't know, use some ball bearings, right. They
Speaker 1: can't hurt.
Speaker 2: No, no, no, and they're always fun to play with,
Speaker 2: although I always lose them.
Speaker 1: But these folks are basically right on the direct approach,
Speaker 1: smash it together, see what comes out. If you have
Speaker 1: enough energy, you can break the electron open. You know.
Speaker 1: That's basically the short answer, and they're right, But nobody
Speaker 1: got the indirect answer. The more subtle, the clever, the
Speaker 1: back door way to maybe see what's inside the electron
Speaker 1: without actually breaking it open, which I'm very excited to
Speaker 1: talk about.
Speaker 2: And I'm very excited to hear the explanation because I
Speaker 2: looked at the outline and I was like, I have
Speaker 2: never heard about this before, so this will be exciting
Speaker 2: and new for me. Let's start from the very beginning.
Speaker 2: You know, we're all made of molecules. Molecules are made
Speaker 2: of atoms. Give me some more detail, what background do
Speaker 2: we need?
Speaker 1: Yeah? Yeah, And I just love this question because I
Speaker 1: love like looking at the stuff around us and wondering,
Speaker 1: like how it comes together? What's the recipe for my coffee?
Speaker 1: What's the recipe for those fish guts? How do we
Speaker 1: end up in this universe? You know? And to me,
Speaker 1: unraveling with things are made of is really like looking
Speaker 1: at the matrix, you know, finding the source code for
Speaker 1: the universe. It's something really deeply satisfying. So it's no
Speaker 1: surprise that I am a particle physicist instead of like
Speaker 1: a rainforest spider ologist. But I hope other people out
Speaker 1: there also find that exciting. And we get to live
Speaker 1: in a time when we have unraveled so much of nature.
Speaker 1: You know, thousands of years ago people were like, I
Speaker 1: don't know, maybe there's four kinds of stuff, who knows.
Speaker 1: But you know, we figured out what used to summarize, like, Okay,
Speaker 1: we're made of molecules, we're made of atoms. That took
Speaker 1: us thousands of years to figure out. It's just like
Speaker 1: obvious high school chemistry by now. But it's also hugely
Speaker 1: revealing about the way our universe works, you know, and
Speaker 1: it tells you something already really powerful, which is that
Speaker 1: you have a huge complexity of stuff, right, Like how
Speaker 1: many different kinds of things are out there in the universe?
Speaker 1: Ice cream and blueberries and mushrooms and fish guts and planets,
Speaker 1: so many things. Maybe infinite numbers of kinds of things.
Speaker 2: Definitely a huge number, even white chocolate unfortunately, but yeah,
Speaker 2: there's a lot of stuff out.
Speaker 1: There, hey said fish cuts, Okay, don't be redundant. The
Speaker 1: amazing thing is that you can build all of that
Speaker 1: with like one hundred atoms, right, It's kind of incredible.
Speaker 1: You put those hundred items together in different ways, and
Speaker 1: you get lava, or you get kittens, or you get hamsters,
Speaker 1: or you get whatever. It's incredible that this huge complexity
Speaker 1: is built out of simplicity, and the complexity comes from
Speaker 1: the arrangements of the stuff. I think that says something
Speaker 1: really deep and powerful about the nature of our universe.
Speaker 1: And so I want to dig deeper, but I want
Speaker 1: to past for a moment and like appreciate how far
Speaker 1: we've come, even just when we get to the atom, right,
Speaker 1: because the universe could have been different. It could have
Speaker 1: been that like everything's made of its own kind of
Speaker 1: particle and there isn't simplicity, or as you get lower,
Speaker 1: there's more and more kinds of stuff. And so I'm
Speaker 1: grateful that we live in the universe where as you
Speaker 1: dig deeper, things seem to get simpler. And it's tantalizing
Speaker 1: because it tells you like, ooh, maybe keep going. There's
Speaker 1: a really simple hints they're waiting for you. It's all
Speaker 1: forty two.
Speaker 2: And as someone who studies behavior, I also think it's
Speaker 2: awesome that we live in a time where you can
Speaker 2: get a bunch of nations together to agree that we're
Speaker 2: interested in the fundamental nature of the universe and we're
Speaker 2: going to invest in something like the LHC. It's just
Speaker 2: I don't know. I think it's an amazing time to
Speaker 2: live for a lot of different reasons.
Speaker 1: Yeah, it is, And so for anybody out there who
Speaker 1: happens to be in the US Congress, for example, I
Speaker 1: think funding for particle physics is great for lots of reasons.
Speaker 1: One is the huge return on investment in terms of
Speaker 1: transforming the nature of society economically and militarily and all
Speaker 1: that stuff. But also just for the sheer knowledge, you know,
Speaker 1: like it's worth it anyway, Let's dig deeper. So we
Speaker 1: have molecules. Molecules are atoms, is like roughly one hundred
Speaker 1: kinds of atoms. Inside the atom, of course, is the
Speaker 1: nucleus and then electrons. Nucleus is made of protons and neutrons,
Speaker 1: and so now we have structure inside the atom, right,
Speaker 1: and don't take that for granted. There's an amazing correlation
Speaker 1: between the structure of the atom and the behavior of
Speaker 1: the atom. All this complexity we're talking about, all the
Speaker 1: fascinating different behavior like why are metals metallic, and why
Speaker 1: something's active and something's inactive. That all comes from the
Speaker 1: structure of the atom. And you could almost have guessed
Speaker 1: it if you looked at the periodic table you said, oh,
Speaker 1: look at these different kinds of atoms. Why there are
Speaker 1: so many different ones, and why are there patterns here?
Speaker 1: You could have guessed that it comes from internal structure.
Speaker 1: That the atoms weren't themselves fundamental, meaning they weren't just
Speaker 1: made of their own stuff. They were made of something smaller.
Speaker 1: So we had a very strong clue already when you
Speaker 1: look at the periodic table that there was more structure
Speaker 1: deep down, and it's amazing that when we dig in
Speaker 1: we find that structure and we're then able to explain
Speaker 1: all of those patterns we saw, right, It's incredible.
Speaker 2: I feel like you just said that chemistry is important,
Speaker 2: and I'm feeling a little uncomfortable. But we talked about this.
Speaker 2: There was a listener question about why is carbon so
Speaker 2: important for life forms and that did come out of
Speaker 2: a long discussion about, you know, what we can learn
Speaker 2: from the periodic, So it's important even if it's chemistry.
Speaker 1: Now I would say it's redundant. All you need to
Speaker 1: know is the structure of the atom, and chemistry you
Speaker 1: should just follow naturally from that if you knew what
Speaker 1: you were doing.
Speaker 2: It's always about physics.
Speaker 1: Exactly anyway. So now let's dig inside the nucleus. Right,
Speaker 1: we have the protons and the neutrons. Protons and neutrons
Speaker 1: we know are made of smaller particles. They're made of quarks,
Speaker 1: and the mass of the proton is fascinating, you know,
Speaker 1: like basically the proton is the mass of hydrogen. That's
Speaker 1: what the hydrogen is, basically just a proton. So fix
Speaker 1: that in your mind is like the unit, and in
Speaker 1: particle physics we use units of GeV giga electron volts
Speaker 1: to talk about mass. It really is GeV divided by
Speaker 1: the speed of light squared, but we just set the
Speaker 1: speed of light to equal one because otherwise it's such
Speaker 1: a pain in the butt. Anyways, So the proton has
Speaker 1: a certain mass. And if you dig into the proton
Speaker 1: and you ask, like, well, the proton is made of
Speaker 1: the quarks. Does that mean I can get the proton
Speaker 1: mass by adding up the mass of the quarks the
Speaker 1: way you feel like if you take your car apart,
Speaker 1: the mass of the car is equal to the mass
Speaker 1: of the parts of the car, right, Well, that's not
Speaker 1: true for the proton, and this is going to be
Speaker 1: very important later. The proton's mass is made of things
Speaker 1: with much much smaller mass. Like you add up the
Speaker 1: mass of the quarks that make up the proton, you
Speaker 1: get like a few percent of its mass. So where
Speaker 1: do the rest of its mass come from? Or? Remember
Speaker 1: mass is not stuff, right, Mass is internal stored energy,
Speaker 1: and there's a lot of energy between those quarks holding
Speaker 1: those quarks together, and that energy inside the proton contributes
Speaker 1: to the proton's mass. The same way, like shining a
Speaker 1: photon into a box of mirrors makes that box more massive,
Speaker 1: even though what you've added hasn't added any actual mass
Speaker 1: on its own. So the proton is pretty massive, but
Speaker 1: it's made of very low mass stuff, and a lot
Speaker 1: of its mass doesn't come from the mass of the
Speaker 1: things that's made out.
Speaker 2: Of this mass is internal stored energy thing. I remember
Speaker 2: you blew my mind when we were talking about that
Speaker 2: in the Where does Energy Come From? Episode? So if
Speaker 2: folks want a bit of a deeper dive into that concept,
Speaker 2: they should check out that episode.
Speaker 1: Yeah, exactly, So we've zoomed it now inside the protons
Speaker 1: and neutrons, and protons and neutrons both made of quarks,
Speaker 1: just different arrangements. You got upcorks and down quarks and
Speaker 1: two upcorks in it. Down makes one of them to
Speaker 1: down quarks and up and makes the other one. Honestly,
Speaker 1: I don't even remember which is which. I can never
Speaker 1: keep that straight, but you can look it up.
Speaker 2: I don't bother memorizing stuff like that either.
Speaker 1: I often remember this stuff, but I feel like if
Speaker 1: you confuse it too many times early on when you're
Speaker 1: learning it, then it's forever scrambled in your brain, and
Speaker 1: I will never be able to snangle them and always
Speaker 1: have to look it up.
Speaker 2: And this is why I'm never going to try to
Speaker 2: say hadrawn, because I've gotten it totally confused. If there
Speaker 2: are some people in my life where I said their
Speaker 2: name wrong so many times, I will never be constantly
Speaker 2: I'm going to say it right where I'm just like, hey,
Speaker 2: I've known you for five years. I don't want to
Speaker 2: mess it up now that we're face to face.
Speaker 1: You remember my name though, right?
Speaker 2: Hey?
Speaker 1: You putting you on the spot.
Speaker 2: It's Whitson right.
Speaker 1: In French they call me Wittissan. I was actually one
Speaker 1: time waiting for an aployment at a bank in France
Speaker 1: and they came out and said Monsieur Wisson and I
Speaker 1: was like, that's not me, and calling him and calling him.
Speaker 1: I was like, who is this moron? We're going for
Speaker 1: your appointment already.
Speaker 2: Your whole never would come with me, oh.
Speaker 1: Exact, oh simla. Anyway, I go to.
Speaker 2: Doctor's appointments, including to the like obgyn, where you think
Speaker 2: that people would be comfortable saying the word wiener. It's
Speaker 2: always like when they call people out from the waiting
Speaker 2: room it's like, oh, uh, you know, miss Smith, Miss Jordan,
Speaker 2: Miss god Luski, uh Kelly, would they get to me?
Speaker 2: And nobody wants to try to say Wiener Smith, even
Speaker 2: at the Obgyn. But anyway, that's all right, I go
Speaker 2: buy anything. It's all fine.
Speaker 1: Maybe they think you're Bird Simpson, you're playing a brank
Speaker 1: on them.
Speaker 2: Yeah, maybe nobody would actually do that. We did one
Speaker 2: We went to go pick up our turkey for Thanksgiving
Speaker 2: it Whole Foods, and they called to the back, the
Speaker 2: wiener Smiths are here for their turkey. And then fifteen
Speaker 2: minutes later we hadn't gotten the turkey, and I was like, hey,
Speaker 2: could you call them in the back and see what's up.
Speaker 2: They called back and they said, what about the turkey
Speaker 2: for the Wienersmith's. And I heard the person on the
Speaker 2: walkie talkie go, oh oh gosh, you were serious. So
Speaker 2: then we got our turkey. All right, I've gotten us
Speaker 2: off track, daniell get us back on track.
Speaker 1: Please, that's right. So we're zooming inside of matter inside
Speaker 1: your frozen turkey. You have molecules and atoms, and those
Speaker 1: are made of protons and neutrons and electrons, and the
Speaker 1: protons and neutrons are made of quarks. So we've zoomed
Speaker 1: all the way down, and everything that you've ever tasted
Speaker 1: or eaten or thrown at your family members on Thanksgiving
Speaker 1: is made of quarks and electrons, right down to this
Speaker 1: very basic Two kinds of quarks and one kind of
Speaker 1: electron can make basically everything. So the particle physicists cookbook
Speaker 1: has three ingredients. And the most amazing thing, the most
Speaker 1: mind blowing to me, is that everything in the universe
Speaker 1: is made of the same ratio of that stuff. It's
Speaker 1: like one proton to one neutron to one electron, which
Speaker 1: means the same numbers of quarks and electrons in everything.
Speaker 1: It's just the arrangement of stuff. But you know, we're
Speaker 1: never satisfied just knowing that it's not like that's the answer,
Speaker 1: and so we're always interested in the question of like,
Speaker 1: is there something deeper? Is there something inside the electron?
Speaker 1: Is there something inside the quarks? And we haven't talked
Speaker 1: about it today and probably won't, But obviously there's a
Speaker 1: huge chunk of the universe dark matter that's not made
Speaker 1: of quarks and leptons, So we know there's other kinds
Speaker 1: of matter out there. Definitely not the end of the story.
Speaker 2: Well, and you said leptons, which we haven't talked about yet.
Speaker 2: What is elepton? Is a lepton like a quark, but
Speaker 2: it jumps a lot. I'm stretched.
Speaker 1: No, it's a particle that's slept in. No electon, Sorry
Speaker 1: for the terminology. There's a category of particles that the
Speaker 1: electron belongs in, and the electron has cousins the muon
Speaker 1: and the towel that make up the other leptons. But
Speaker 1: we can also do say quarks and electrons because that's
Speaker 1: what makes up the matter that we are made out of.
Speaker 1: There are other quarks out there, and there are other
Speaker 1: versions of the electron out there, the muon and the towel,
Speaker 1: but our kind of matter is made out of two quarks,
Speaker 1: the up and the down, and the electron.
Speaker 2: Got it, Okay, So after the break, we're going to
Speaker 2: talk about why we think that digging into the electron
Speaker 2: is worth it doing. Do we have any evidence to
Speaker 2: suggest there's something else making that up? And we'll discuss
Speaker 2: that after the break and we're back. Okay. So we've
Speaker 2: dug into protons and neutrons. We know that there's quarks
Speaker 2: that are making them up. Do we have any indication
Speaker 2: that if we dig farther into electrons we will find
Speaker 2: that electrons are made up out of something.
Speaker 1: We have no really direct smoking gun, right. What we
Speaker 1: do have is a sort of history and some hints
Speaker 1: that encourage us. Recall when we were talking about the
Speaker 1: periodic table. We saw all these patterns in the periodic
Speaker 1: table and we were wondering, could that be explained by
Speaker 1: internal structure? Could these actually all be made out of
Speaker 1: smaller bits? And the patterns come from how those bits
Speaker 1: arrange themselves and come together naturally, from the different ways
Speaker 1: that they can click together, or whatever. And now we
Speaker 1: know the answer is yes. So we can also look
Speaker 1: at the current list of particles that we don't know
Speaker 1: what's inside and ask are there patterns there? Are there
Speaker 1: unexplained phenomena, things that seem suggestive that maybe these are
Speaker 1: built out of the same smaller bits. The answer to
Speaker 1: that is, oh, yeah, absolutely, there are huge, obvious, screaming
Speaker 1: patterns that suggest very strongly this is not the final answer.
Speaker 2: And if you were to find something fundamental making up electrons,
Speaker 2: what would you name it?
Speaker 1: The white son? Of course?
Speaker 2: The what toll exactly?
Speaker 1: So yeah, I hope I'm around to do that, and
Speaker 1: I suspect the particle physics community would overrule me, and
Speaker 1: that happens occasionally, you get overruled, like the electron discovered
Speaker 1: by JJ Thompson. He didn't call it the electron. He
Speaker 1: wanted to call them corpuscules, like little bits of matter.
Speaker 1: But people are like, yeah, no, we're going to go
Speaker 1: with electron.
Speaker 2: I mean, as long as they don't name it like
Speaker 2: A or B, like what was it Jupiter's rings? It
Speaker 2: needs to be something exciting. But okay, all right, so
Speaker 2: tell me more about these tantalizing patterns.
Speaker 1: Yes, So we mentioned earlier that there's more than just
Speaker 1: the electron, right, the electron has cousins. There's the muon
Speaker 1: in the towel, so there's three kinds of electrons. The
Speaker 1: electron also has a partner, the new trino, which isn't
Speaker 1: part of our matter, but it's part of the universe.
Speaker 1: It's something the universe can do. So in total, there
Speaker 1: are six of these lepton particles, the electron, muon, TAW,
Speaker 1: and then the three neutrinos that correspond to them. So
Speaker 1: that's interesting and you might ask like, well, why are
Speaker 1: there three these particles are all so closely related that
Speaker 1: muon is just a little heavier than the electron. The
Speaker 1: toaw is even heavier. It feels like you patterns in
Speaker 1: the periodic table. There's like three columns of these particles.
Speaker 1: So that's already very interesting and suggestive. It makes you wonder, like,
Speaker 1: are there three ways to click together their internal bits?
Speaker 1: And this is how it happens, three ways for some
Speaker 1: string inside of it to vibrate. And that's just one
Speaker 1: of the really interesting patterns. That whole pattern of like
Speaker 1: six particles three pairs of two is also reflected in
Speaker 1: the quarks. We talked about the quarks the up and
Speaker 1: the down. That's one doublet of quarks up and the
Speaker 1: down go together. There's a copy of that doublet the
Speaker 1: charm and the strange, very similar to the up and
Speaker 1: the down, but heavier. And then there's another copy of
Speaker 1: that doublet the top and the bottom. So all in
Speaker 1: all the quarks have six and it breaks into these
Speaker 1: three columns of two particles exactly the same way the
Speaker 1: leptons do. So you have this structure which is interesting
Speaker 1: and suggestive, and then you have it repeated in another
Speaker 1: set of particles. The amazing thing is that the quarks
Speaker 1: and leptons are very different. The quarks feel the strong force,
Speaker 1: the leptons don't. The quarks make up the nucleus, the
Speaker 1: leptons make up the stuff that orbits around it. We
Speaker 1: don't actually know what the relationship is between quarks and leptons,
Speaker 1: yet there's this very strong symmetry between them. It's like
Speaker 1: if you go into a suburban street and you see,
Speaker 1: like all the houses on the left have this one
Speaker 1: floor plan, all the houses on the right have this
Speaker 1: other floor plan, but they're similar. You might be like, oh, okay,
Speaker 1: well this is obviously built by one company and they
Speaker 1: got two floor plans, right, it's the same deal. It's
Speaker 1: like the universe can do this or it could do that,
Speaker 1: and probably they're built out of the same bits, you know, Like,
Speaker 1: for example, the charge of the proton is plus one
Speaker 1: and the charge of the electron is minus one. Those
Speaker 1: two things cancel exactly. For that to happen, there has
Speaker 1: to be some relationship between the quarks and leftons. Can't
Speaker 1: just be chance that the quarks add up to make
Speaker 1: plus one and the electron adds up to make minus one.
Speaker 1: So there's definitely some connection there. But we don't know
Speaker 1: what it is. So all of this to me are
Speaker 1: very obvious clues. And in one hundred years, when we
Speaker 1: know what's inside the electron and the quarks, people will
Speaker 1: be like, God, it was so obvious. How did you
Speaker 1: not see it? Right? But right now we don't know.
Speaker 1: We know that we have these patterns, and it could
Speaker 1: be that the universe is just this way, that all
Speaker 1: this stuff is fundamental and the universe has made it
Speaker 1: of these complex bits with these weird patterns, and there
Speaker 1: is no explanation, but I refuse to believe it. I
Speaker 1: think that everything out there should be explained.
Speaker 2: So if we've got you know, three different kinds of neutrinos,
Speaker 2: they've got up and down quarks, charm and strange and
Speaker 2: top and bottom charm and strange was a good naming thing.
Speaker 2: When we break the electron into its component parts, do
Speaker 2: we expect there to be two parts then, to match
Speaker 2: with what we're seeing with the neutrinos.
Speaker 1: Yeah, good question. We don't know. There could be made
Speaker 1: of two things, could we have three things? Could just
Speaker 1: be made of itself. Whatever is down there is going
Speaker 1: to be very different from what we've seen before. And
Speaker 1: you know, when we saw the proton, it was made
Speaker 1: out of three things. And it's interesting it's made of
Speaker 1: three things because of the way the strong force works.
Speaker 1: There's three colors, and one way to get a balance
Speaker 1: is to have all three colors, you know. It's not
Speaker 1: just like a plus charge and a minus charge is red, green, blue,
Speaker 1: and if you have a red, green, and a blue,
Speaker 1: it comes together to make a color neutral object, which
Speaker 1: is stable. So one reason why the proton is made
Speaker 1: out of three is for that reason, because of the
Speaker 1: structure of that force. So we don't know what force
Speaker 1: is holding together the quarks or the electrons, and that's
Speaker 1: what would determine how many pieces there are and how
Speaker 1: they interact, you know. And so it could be that
Speaker 1: the electron is fundamental. It's just made of itself, and
Speaker 1: when the coders of our simulation put together the universe,
Speaker 1: they started with electrons and that's it, and there's just
Speaker 1: nothing else inside. But it could also be that it's
Speaker 1: made of smaller stuff. The frustrating thing is that you
Speaker 1: can never prove that something is fundamental, right. You can
Speaker 1: prove it's not by breaking it open and seeing what's inside.
Speaker 1: But all you can do is not to discover that
Speaker 1: it is made of something. That doesn't prove that it
Speaker 1: is fundamental, right, just shows that, well, maybe it's fundamental,
Speaker 1: or maybe it's stuff that's so small you can't see,
Speaker 1: or it's bound together so tightly you can't break it open,
Speaker 1: so you can never actually prove that it's fundamental.
Speaker 2: The universe can be very frustrating that way.
Speaker 1: And it might also be this is really philosophical, that
Speaker 1: there's nothing fundamental, like maybe the electron is made of
Speaker 1: something else, Schma electrons and those are made of something else,
Speaker 1: but electrons and those are made of something else, is
Speaker 1: made of something else. And your instinct is, well, there's
Speaker 1: got to be something at the bottom, right, it's got
Speaker 1: to be a bedrock layer of reality. And maybe but
Speaker 1: that's just a philosophical hunch, you know, we have no
Speaker 1: evidence that there is. There are theories out there in
Speaker 1: philosophy that the universe could just be an infinite ladder
Speaker 1: of particles with no bottom, right, it just goes on forever,
Speaker 1: which would be great for particle physics because like infinite funding, right,
Speaker 1: just keep.
Speaker 2: Digging infinite nobels. Yeah, there go, there you go.
Speaker 1: But that could be our reality, right, it's possible, but
Speaker 1: there also could be a bedrock, and that's what I
Speaker 1: hope for. I hope that we get someday to some
Speaker 1: set of particles that's so simple, so basic, so obvious
Speaker 1: and beautiful that we think, okay, this must be it.
Speaker 1: It would make sense for the universe to have this
Speaker 1: beats fundamental, because it'd be very unsatisfying if the answer
Speaker 1: is what we have today. The answer is, well, there
Speaker 1: are twelve matter particles and there are five forced particles,
Speaker 1: and that's just it. They're seventeen and that's the basic
Speaker 1: elements of the universe, and that's what we start from.
Speaker 1: And like, really, come on, it's got to be simpler
Speaker 1: than that. We have this tendency towards simplicity, and I
Speaker 1: just hope that the march continues, but there's no guarantees, so.
Speaker 2: I gotta be honest. Before you and I started talking regularly,
Speaker 2: I also held out hope that they were like simple, beautiful,
Speaker 2: elegant answers. And then you told me about the weak force.
Speaker 2: That was the moment for me where I'm like, I
Speaker 2: don't think any of this is gonna make sense. We're
Speaker 2: just gonna have to keep buddling our way through. But
Speaker 2: hopefully I'm wrong.
Speaker 1: So I ruined your view of particle physics. Used to
Speaker 1: think of it as like a shining cathedral of simplicity
Speaker 1: and beauty, and then you're like, man, this is a
Speaker 1: mess that's.
Speaker 2: All held together with zip ties and duct tape in there.
Speaker 2: I don't know what's going on, but it is.
Speaker 1: Yeah, But you know, at least now we understand why
Speaker 1: the weak force is a mess. They used to just
Speaker 1: be like, gosh, this is kind of ugly, and now
Speaker 1: we see, oh, it was beautiful and it was shattered
Speaker 1: by the Higgs boson in this precise way, and that's
Speaker 1: at least satisfying, and we can explain it, and we
Speaker 1: can hark back to an earlier day in the universe
Speaker 1: before it all got messed up. Something satisfying there, and
Speaker 1: I hope we get that kind of explanation.
Speaker 2: All right, sounds good. I'm sure the more I learn,
Speaker 2: the more satisfied I'll become. That's so nice of you,
Speaker 2: You know, you make a strong effort to be interested
Speaker 2: in biology. We're both supporting each other here. So let's
Speaker 2: talk about the methods that are currently being used to
Speaker 2: try to break electrons into smaller pieces. If that's a
Speaker 2: thing that exists.
Speaker 1: Yeah, all right, So the most obvious thing is what
Speaker 1: the listener suggested, which is like, hey, let's smash it open, right,
Speaker 1: Take two electrons or an electron and a positron, doesn't
Speaker 1: really matter, point them at each other, give them a
Speaker 1: lot of energy, and bounce them off each other. See
Speaker 1: what happens. Like This method works also for things like toasters. Right,
Speaker 1: want to know what's inside your toaster? Take two toasters,
Speaker 1: throw them at each other at really high speeds. You're
Speaker 1: gonna have a shower of stuff that comes out, and
Speaker 1: you can sift through the debris and be like, oh
Speaker 1: look there's two springs and there's two handles, and oh okay,
Speaker 1: this must be what the toaster is made out of.
Speaker 2: An ouch just should have unplugged it first.
Speaker 1: That's a long extension cord. And there's something fundamentally different
Speaker 1: about the way it happens or quantum particles, but the
Speaker 1: spirit is the same. I mean, if you smash two
Speaker 1: toasters together, you're not destroying parts of the toaster and
Speaker 1: converting their math into energy and trains meeting them into
Speaker 1: something else. The bits that come out of the toaster
Speaker 1: collision are the same bits that went into the toaster collision.
Speaker 1: In a quantum collision, you can annihilate the particles like
Speaker 1: eve an electron and a positron. They can annihilate into
Speaker 1: a photon and then turn into something else. Crazy. What
Speaker 1: comes out isn't always what went in, right, So you're
Speaker 1: not always learning about what's inside the electron if you
Speaker 1: annihilate it.
Speaker 2: So, say you smashed two toasters into each other, and
Speaker 2: you expected to see like screws and springs and stuff
Speaker 2: like that. We don't even know what we should expect
Speaker 2: to see when you break the electron. And so if
Speaker 2: you know, things we had never seen before came out
Speaker 2: of the toaster, like fish cuts, fish guts, exactly, how
Speaker 2: would we even know what to do with that? And so, like,
Speaker 2: how do we know what to look for or how
Speaker 2: to measure it if we've never seen it before?
Speaker 1: Yeah, good question. It would be amazing if we discover
Speaker 1: this fish all the way down.
Speaker 2: I'm skeptical.
Speaker 1: The simplest version of what we do is that we
Speaker 1: start at low energy and we know what we expect
Speaker 1: to see. Like, if you shoot two electrons at each
Speaker 1: other at fairly low energy, they're going to bounce off
Speaker 1: each other in a way that's similar to what happens
Speaker 1: if you shoot two baseballs at each other. They're going
Speaker 1: to bounce off, and you can calculate the angles they're
Speaker 1: going to come out at and the energy. And they're
Speaker 1: quantum particles, so you can't predict an individual one, but
Speaker 1: you can predict the distribution. And so if you have
Speaker 1: what we call elastic scattering, which means you're not breaking
Speaker 1: the particles open, you know, changing the configuration they're just
Speaker 1: bouncing off each other is very predictable. So you start
Speaker 1: with that and you see the distributions you expect, the
Speaker 1: angles that you expect, you're like, okay, that's cool. And
Speaker 1: then you increase the energy, and like with baseballs, at
Speaker 1: some point when you increase the energy, you're going to
Speaker 1: get what we call an inelastic collision, which means the
Speaker 1: baseballs shatter or they stick together, or something else happens. Right,
Speaker 1: And it's an energy threshold because the baseball's help together
Speaker 1: with energy, right, it's bound together. And if you have
Speaker 1: a high enough energy, you can break those bonds. If
Speaker 1: you don't, you don't, So below some energy threshold, you're
Speaker 1: not probing inside the baseball. You're probing the baseball behavior itself,
Speaker 1: but above some energy, it's inelastic, and then the distribution changes. Yeah,
Speaker 1: maybe a baseball comes out, but first of all, it's mangled.
Speaker 1: It looks different, and the angles look very different. Like
Speaker 1: if you collide to baseballs and they stick together, they
Speaker 1: don't come back out at you in the same way.
Speaker 1: Or imagine if you're doing it, like you throw a
Speaker 1: baseball at a wall, and if you throw it low energy,
Speaker 1: it bounces off, it doesn't break the wall. Throw it
Speaker 1: high enough energy, baseball just doesn't come back right. It
Speaker 1: just goes through the wall. So that's very different. And
Speaker 1: so that's what you look for to see. If you're
Speaker 1: probing inside a particle, you shoot it at higher, higher
Speaker 1: and energy, and you look for deviations from the distributions
Speaker 1: you would expect from elastic scattering to see that you're
Speaker 1: starting to do inelastic scattering. You're starting to probe maybe
Speaker 1: what's inside the particles instead of probing the particles as
Speaker 1: a whole.
Speaker 2: We found an energy at which we can shoot electrons
Speaker 2: at each other where it looks like we're transitioning from
Speaker 2: elastic to inelastic scattering.
Speaker 1: Unfortunately not yet, but This is exactly how we discovered
Speaker 1: the structure of the proton. We shot electrons and protons
Speaker 1: at each other, and a low energy they bounce off
Speaker 1: elastic scattering. At higher energy, you start to destroy the proton,
Speaker 1: and what's happening is the electron is now interacting with
Speaker 1: the quarks inside of it, and so at some energy
Speaker 1: you start to just get like shrapnel from the proton
Speaker 1: and it's definitely not elastic scattering, so you can tell
Speaker 1: you're doing inelastic scattering. For people who want to learn
Speaker 1: more about these experiments, they're fascinating and amazing. They're called
Speaker 1: deep in elastic scattering, so you can google that. And
Speaker 1: if you get to high enough energy, you actually start
Speaker 1: to see elastic scattering from the things inside the proton.
Speaker 1: And that's, for example, how we know we have three
Speaker 1: quarks inside the proton, because you shoot electrons at the
Speaker 1: proton and you start to get elastic scattering as if
Speaker 1: there are three tight little dots of objects that you're
Speaker 1: interacting with. Because at high enough energy, the bonds of
Speaker 1: the quarks are irrelevant. If your energy of your probe
Speaker 1: is larger than the energy of the bonds between the quarks,
Speaker 1: you're just shooting it at three quarks and sometimes they
Speaker 1: bounce off and exactly the way you would expect from
Speaker 1: elastic scattering between electrons and quarks. So it's this incredibly
Speaker 1: beautiful transition from elastic to inelastic to then three times
Speaker 1: elastic scattering. It's really amazing.
Speaker 2: That must have been so cool to realize that you,
Speaker 2: instead of a proton, now have three other things that
Speaker 2: have popped out and be like the answer is three.
Speaker 1: Yeah, I don't know.
Speaker 2: That sounds really cool to me.
Speaker 1: It is really cool, but for a while people didn't
Speaker 1: believe it. They're like, okay, well that's cool and that's clever,
Speaker 1: but that's just mathematics, Like is that real. And for
Speaker 1: a long time people call these partons like parts of
Speaker 1: the proton, and nobody believes that they were like actually
Speaker 1: physically real things inside the proton until somebody predicted, like, okay,
Speaker 1: well if these things are real, these quarks are real,
Speaker 1: they should be able to do other things also, like
Speaker 1: make other states bound together. And somebody predicted one of
Speaker 1: these states. And the day they saw this in the experiment,
Speaker 1: is this new state made of just these quarks together.
Speaker 1: That's when everybody started to believe Okay, quarks are real.
Speaker 1: It's called the October Revolution. It was a very yeah,
Speaker 1: absolutely in physics. And a guy I worked with tells
Speaker 1: a story about his father who's also a particle physicist,
Speaker 1: getting a phone call that day in October and like
Speaker 1: leaping out of the shower naked and dripping wet because
Speaker 1: he knew he was going to be exciting news to
Speaker 1: take that phone call. So sometimes there is drama in
Speaker 1: particle physics. And so that's what we saw for the
Speaker 1: inside the proton. We know the proton has structure, and
Speaker 1: that's how we know, and we can try the same
Speaker 1: thing shooting electrons at each other. But so far we've
Speaker 1: seen no structure.
Speaker 2: And have we gone up to what you would consider
Speaker 2: to be very very very high energies doing these experiments, Well.
Speaker 1: We've done the highest we can, right. The large hadron
Speaker 1: collider is the highest energy collisions of protons and protons,
Speaker 1: and before that we had a high energy electron collider.
Speaker 1: You know, we built these things as large as we can.
Speaker 1: The limitation is just money, Like, there's no fundamental limitation
Speaker 1: to building a bigger collidse. We know how to do it.
Speaker 1: It just costs a lot of cash. You got to
Speaker 1: build a tunnel, you got magnets, you got little accelerating modules.
Speaker 1: We could, in principle build one that circumnavigates the moon
Speaker 1: or you know, the galaxy or whatever. You just cost
Speaker 1: a zillion dollars, and even I think that's probably not
Speaker 1: a good way to spend to your cash. But it's
Speaker 1: awesome sort of to think that, like we could just
Speaker 1: buy this knowledge of the universe, Like it's out there,
Speaker 1: we're in the candy store, we have the money in
Speaker 1: our pockets. We're just like, hmmm, I feel like that
Speaker 1: Snickers bar is too much money.
Speaker 2: Maybe we should figure out what causes cancer.
Speaker 1: Yeah, exactly, save some kids from dying. Exactly. So one
Speaker 1: approach is like, just build bigger colliders. But the problem
Speaker 1: is we don't know how big it has to be,
Speaker 1: Like until you see the inside of the electron, you
Speaker 1: have no idea. Is it right beyond our capability if
Speaker 1: we build it a little bit bigger we see it,
Speaker 1: or is it going to require a solar system sized
Speaker 1: collider or a galaxy sized colider or use black holes
Speaker 1: or just like a revolution in collider technology, so we
Speaker 1: don't need to make them so big and expensive something
Speaker 1: are working on that, So it's an exploration game the
Speaker 1: same way. You don't know when you land on an
Speaker 1: alien planet is going to be all dust and rubble?
Speaker 1: Or are the aliens waiting for us? And you want
Speaker 1: to land on as many planets as possible. We don't
Speaker 1: know when we build a collider, are we about to
Speaker 1: see inside the electron? Or is this thing way too
Speaker 1: small and we're not going to see anything. You just
Speaker 1: don't know, all right.
Speaker 2: Well, so we've talked about direct methods of trying to
Speaker 2: figure out if electrons are made of smaller parts. Next,
Speaker 2: you are going to tell us about the indirect method
Speaker 2: that you queued up for us as a super exciting
Speaker 2: thing earlier in the episode, And when we get back
Speaker 2: from the break, we're going to learn all about it.
Speaker 2: We're back and during the break I asked Daniel if
Speaker 2: the indirect method required bigger colliders, and he said the
Speaker 2: answer is no, which means maybe this could be the
Speaker 2: key with existing technologies for figuring it out exactly. I'm
Speaker 2: super excited. How do we do this indirectly?
Speaker 1: Yeah? So, particle physicists loves smashing stuff together and they
Speaker 1: love making bigger and bigger colliders, and that's all fun
Speaker 1: and everybody would prefer to do it's a direct way.
Speaker 1: It's the most fun, it's the most obvious, it's the cleanest,
Speaker 1: the data is beautiful. But hey, it's expensive, and you know,
Speaker 1: it's hard to build new colliders, and so we also
Speaker 1: try to be resourceful and we try to find other
Speaker 1: ways to discover things without having to build the collider
Speaker 1: to make them directly. So we have these indirect methods
Speaker 1: of discovering things. Essentially, if we can see the influence
Speaker 1: of some new particle, for example, on the particles we
Speaker 1: already are able to make in the collider, even if
Speaker 1: we don't have enough energy to make that new particle,
Speaker 1: that can still influence the particles we have. So for example,
Speaker 1: before we discovered the top quark, we were pretty sure
Speaker 1: it was there, and we're pretty sure we knew where
Speaker 1: it was, like how much mass it had because of
Speaker 1: the way it influenced the particles we were able to
Speaker 1: make at the lower energy colliders. So we can play
Speaker 1: this indirect game of seeing the influence of new particles
Speaker 1: out there on the particles we see to discover new
Speaker 1: particles without like having the energy to make them, but
Speaker 1: we can also do something similar to see inside the
Speaker 1: electron using a very clever trick of studying the Higgs boson.
Speaker 1: So you remember, the Higgs boson is the particle it
Speaker 1: messes up the weak force, but also it gives mass
Speaker 1: to all the particles, like it gives mass to the electron,
Speaker 1: for example, by interacting with it. So without the Higgs boson,
Speaker 1: the electron would have no mass. It would be a
Speaker 1: speed of light, massless particle, similar to the photon, but
Speaker 1: with charge. Of course, once you have the Higgs boson
Speaker 1: in the universe, the Higgs and the electron interact, and
Speaker 1: so the electron that we see is not the pure electron.
Speaker 1: It's the electron interacting with the Higgs field, and that
Speaker 1: interaction is sort of like a big pulsing ball. The
Speaker 1: energy is sliding back and forth between the electron field
Speaker 1: and Higgs field, back and forth constantly, and that basically
Speaker 1: counts as internal stored mass of this thing, this thing
Speaker 1: which is a combination of the electron in the Higgs field.
Speaker 1: We talked in the Charge episode about how fields are
Speaker 1: coupled together sloshes back and forth between them. That's what's
Speaker 1: happening with the electron field and the Higgs field. So
Speaker 1: the thing that we see is not really a pure electron.
Speaker 1: What we call the electron is actually a combination of
Speaker 1: the electron field and the Higgs field, and that thing
Speaker 1: has energy inside of it because of this interaction, and
Speaker 1: that's where the electrons mass comes from. Still with me,
Speaker 1: So I'm.
Speaker 2: Trying to connect what you just said and thinking about
Speaker 2: what we were talking about before. So is this interaction
Speaker 2: going to give us more energy than you would get
Speaker 2: if you were just smashing electrons together. No, that's not
Speaker 2: what we're going for. We're just expecting the interactions to
Speaker 2: be different in a way that is formative.
Speaker 1: Yeah, exactly. You can't use that as a source of
Speaker 1: fuel to like push things further or anything. But what's
Speaker 1: really fascinating is that the electron has a different mass
Speaker 1: than the muon. For example, right, muon is the cousin
Speaker 1: of the electron. Muon has a lot more mass, interacts
Speaker 1: much more strongly with the Higgs boson, and so the
Speaker 1: Higgs boson interacts with the muon more intensely. So the
Speaker 1: muon has more mass. And that's really interesting because it
Speaker 1: means that by studying the interaction between the Higgs boson
Speaker 1: and a particle, you can understand how much mass it
Speaker 1: should have. Like if you knew the strength of the
Speaker 1: interaction between the Higgs boson the electron, you could predict
Speaker 1: the electrons mass. You'd be like, Okay, I know how
Speaker 1: much these two fields couple together, so I can calculate
Speaker 1: how that little pulsling ball of energy should be and
Speaker 1: I can predict the electrons mass. Right, And the same way,
Speaker 1: you know, Okay, the muon interacts more strongly with the Higgs,
Speaker 1: so we should have a higher mass. And the top
Speaker 1: quark crazy interaction with the Higgs. Huge mass for the
Speaker 1: top quark. Top quark is like two hundred times the
Speaker 1: mass of the proton, which is much more massive than
Speaker 1: the electron. So enormous variations in the amount that the
Speaker 1: Higgs boson interacts with this stuff. So say you knew
Speaker 1: how the Higgs boson interacts with these particles, you could
Speaker 1: predict their mass, and then you went out and you
Speaker 1: measured their mass, and what if you saw a discrepancy.
Speaker 1: What if the Higgs boson interacts with the electron and
Speaker 1: it should give it a mass of like zero point one.
Speaker 1: But you go out and you measure the mass and
Speaker 1: it's point five where it's ten point zero, then you'd
Speaker 1: be like, hold on a second, the electron has more
Speaker 1: mass than it's getting from the Higgs boson. We think
Speaker 1: the Higgs boson is giving the electron a certain amount
Speaker 1: of mass, but we can go out and measure it
Speaker 1: in the universe it has more mass than that. What
Speaker 1: could that mean. Well, we've seen that before, haven't we.
Speaker 1: The proton is made of three quarks, and those quarks
Speaker 1: get their mass from the Higgs boson, But the proton
Speaker 1: gets most of its mass not from the Higgs boson,
Speaker 1: but from the interaction of the quarks, and so in
Speaker 1: a similar way, if you measure the mass of the
Speaker 1: electron and it's heavier than you can explain with the
Speaker 1: Higgs boson, that means that it's got some energy inside
Speaker 1: of it, some bonds that are holding its bits together.
Speaker 1: That its mass is not just coming from the Higgs boson.
Speaker 1: Its mass is coming from the interaction of the things
Speaker 1: inside of it, which means there are things inside of it. Haha,
Speaker 1: look at that, ha ha.
Speaker 2: But that doesn't tell us how many things are inside
Speaker 2: of it, or the nature of the things inside of it.
Speaker 1: Don't throw cold water on our discovery. Oh my god,
Speaker 1: we just had an aha moment. We revealed something about
Speaker 1: the universe, and now you're not sad.
Speaker 2: Now I'm excited. I'm excited. I'm just trying to figure
Speaker 2: out how excited.
Speaker 1: I should be. No, you're totally right. The indirect method
Speaker 1: is not as exciting as the direct method. It tells
Speaker 1: us that there is something inside of it, and you
Speaker 1: can tell us something about the nature of those bonds.
Speaker 1: But you're right, it doesn't tell us what it is.
Speaker 1: It doesn't show it to us, It doesn't give it
Speaker 1: to us to play with.
Speaker 2: But has this been done?
Speaker 1: So this is what we're working on. And this is
Speaker 1: something we can do with a large hadron collider because
Speaker 1: we can study the interaction of the Higgs boson in
Speaker 1: various particles. Who The way we do that is by
Speaker 1: measuring how often the Higgs boson turns into those particles.
Speaker 1: Like you create a Higgs boson, does it turn into
Speaker 1: a pair of bottom quarks or a pair of top quarks,
Speaker 1: or a pair of electrons or a pair of muons.
Speaker 1: The rate at which it interacts with these particles determines
Speaker 1: how often it turns into those particles, so electrons very
Speaker 1: very low mass, low interaction with the higgs, very rare.
Speaker 1: To see higgs turn into electrons very difficult, but you
Speaker 1: run the collider long enough, you'll see it and you'll
Speaker 1: be able to measure that, and then we can compare
Speaker 1: that to the mass of the higgs. So we don't
Speaker 1: have that number yet because the higgs decase to electrons
Speaker 1: very very very rarely because they're so light. But we're
Speaker 1: starting to be able to measure that for other particles.
Speaker 1: So we've measured it for the top cork and for
Speaker 1: the bottom cork, and those numbers are as we expect.
Speaker 1: So the higgs boson de case to the top cork
Speaker 1: in a way that suggests that all of its mass
Speaker 1: comes from the higgs boson. I mean, you would have
Speaker 1: heard about it already if we discovered something inside the quarks.
Speaker 1: So far the number is don't indicate that there's anything
Speaker 1: inside the top cork or the bottom cork. We haven't
Speaker 1: been able to probe the other particles because they're lower
Speaker 1: masks and therefore the higgs the case to them more rarely.
Speaker 1: But that is something we can do, and we have
Speaker 1: ten more years to run this collider and get all
Speaker 1: that data and analyze these things. And I just think
Speaker 1: it's cool that we have sort of these backdoor methods
Speaker 1: to be like, well, let's look to see if we
Speaker 1: can figure out if there is something there before we
Speaker 1: actually build the collider to break it open and show
Speaker 1: it to us.
Speaker 2: Yeah. So say you had an electron a muon what
Speaker 2: is a tau town?
Speaker 4: Good?
Speaker 2: Right? Towh man, it was so cool question stuff.
Speaker 1: I'm rounding you up to any of plus.
Speaker 2: All right, thank you? Great? Oh yeah, okay, So you've
Speaker 2: got these three things and you interact them with the
Speaker 2: Higgs if the answer for their mass differs in some
Speaker 2: predictable way, like you know, one is always twenty five
Speaker 2: percent higher than the other, and then the other one
Speaker 2: is another twenty five percent beyond that, could you guess
Speaker 2: how many there were in there, like you know, there's
Speaker 2: probably three, and then there's an additional one in this
Speaker 2: one and an additional one in that one, Like could
Speaker 2: you get a handle on like the relative numbers of
Speaker 2: things that way?
Speaker 1: Yeah, that's exactly the game we'd love to play. You know,
Speaker 1: look at these things, look for patterns, look for clues.
Speaker 1: If we saw this, there would be instantly a zillion
Speaker 1: theories explaining it, you know, to match all those numbers,
Speaker 1: which would be really fun. And you know, we need
Speaker 1: that kind of inspiration. We need this kind of data
Speaker 1: to give us a clue to come up with these ideas.
Speaker 1: There are lots of theories of electron compositeness, you know,
Speaker 1: things that could be inside the electron, but nobody's any
Speaker 1: idea if any of them are true. Maybe the most
Speaker 1: famous is string theory. String theory says all the particles
Speaker 1: are just string oscillating in different ways, which is cool
Speaker 1: and very beautiful, but strings are so tiny that we
Speaker 1: could never see them with a direct method, like we
Speaker 1: would need a ridiculous collider to see strings. And you know,
Speaker 1: not everything that's inside the electron could be seen even
Speaker 1: with this indirect method, because it has to couple to
Speaker 1: the Higgs boson. In order for this to work, it
Speaker 1: has to directly get its mass from the Higgs boson
Speaker 1: the constituents of the electron. It could be that the
Speaker 1: constituous electron don't get their mass from the Higgs boson,
Speaker 1: and the electron itself is some like effective approximate description
Speaker 1: of it, and it gets its mass directly from the
Speaker 1: Higgs boson, unlike the proton, for example. So there are
Speaker 1: ways that this could fail, but it's an exciting way
Speaker 1: to see inside the electron anyway.
Speaker 2: So is this the kind of thing where, like tomorrow,
Speaker 2: the news could be saying, oh my gosh, using the
Speaker 2: indirect method, we are now sure that the electron is
Speaker 2: made up of stuff. You said something about a decade's
Speaker 2: worth of data. Is this the kind of thing where
Speaker 2: we're gonna need ten years to figure it out? To
Speaker 2: see a signature, We're gonna.
Speaker 1: Need a while. This is hard. You're measuring something that's
Speaker 1: very very rarely happens, and then you want to measure
Speaker 1: very precisely, which means you need a bunch of examples.
Speaker 1: But this is what we're good at, you know, we
Speaker 1: are good at using machine learning to extract this information
Speaker 1: from the data to get the most juice out of
Speaker 1: the dollars that we have spent on it. And you know,
Speaker 1: this is what particle physicists do. We're blocked by this wall,
Speaker 1: so let's see if we can find a way around it.
Speaker 1: And I'm impressed with the cleverness. I mean, I didn't
Speaker 1: come over this. Yeah, somebody else thought of this, and
Speaker 1: it just goes to show you the ingenuity of humanity.
Speaker 1: You know, there are questions we have, and we will
Speaker 1: always push to find the answers, even if it seems
Speaker 1: impossible or impractical or ridiculously expensive, we will find a
Speaker 1: way to get there.
Speaker 2: So you said that the LEDC right now mostly has
Speaker 2: protons shooting around. So are we even collecting the right
Speaker 2: kind of data to use the indirect method right now
Speaker 2: or is that happening at like a different collider.
Speaker 1: No, proton shooting around is a good way to make
Speaker 1: Higgs bosons. One thing that LEDC is really good at
Speaker 1: is making Higgs bosons. It was built to discover the Higgs,
Speaker 1: but it was also built to discover lots of different
Speaker 1: versions of the Higgs, because we didn't know in advance
Speaker 1: how much mass the Higgs would have, and so exactly
Speaker 1: the best way to make it. So proton collider is
Speaker 1: really good at discovering things you don't know much about,
Speaker 1: because it can make lots of different kinds of things.
Speaker 1: Now that we know more about the Higgs boson, people
Speaker 1: are talking about making a Higgs factory, which is a
Speaker 1: machine that makes zillions and zillions of higgs. It's like
Speaker 1: perfect for making higgs, and it does it by colliding
Speaker 1: muons actually, so you make beams of muons because muons
Speaker 1: interact with the higgs more than the electrons do. This
Speaker 1: is a good way to make lots of higgs. It's
Speaker 1: really hard to make muon beams because muons don't last
Speaker 1: very long that the k back into electrons. But people
Speaker 1: have figured that out. So that's one thing on the
Speaker 1: docket for the next colliders. Maybe make a big muon
Speaker 1: collider higgs factory so you can study these things incredible detail.
Speaker 1: So that'd be exciting, but of course you know that
Speaker 1: cost a few bill Yeah, yeah.
Speaker 2: I would like to make a discovery there where people
Speaker 2: can say, like, well, we need to make more Wienersmiths,
Speaker 2: make more higgs. Like that's a person and that's just
Speaker 2: so great that his name has become, you know, used
Speaker 2: in that way. But anyway, maybe one day they'll be
Speaker 2: wanting to make more Wienersmiths, but maybe not.
Speaker 1: Maybe one day, And I hope that in a one
Speaker 1: hundred years or a thousand years, people know more about
Speaker 1: the structure of matter and they can talk about the
Speaker 1: fundamental bits and you can smoke banana peels on the
Speaker 1: roof and talk about why the universe is made out
Speaker 1: of squiggly ons and what that even means and why
Speaker 1: are the two of them? And you know, to me,
Speaker 1: these are fun philosophical questions and we don't even get
Speaker 1: to ask them yet because we don't know what those
Speaker 1: answers are. And I hope to live long enough to
Speaker 1: see some of that.
Speaker 2: Yeah, but it's cool that we live in a time
Speaker 2: where you can devise the experiments to ask these questions
Speaker 2: that we've gotten this far down the ladder. So I'm excited.
Speaker 1: The ancient Greece would be very impressed.
Speaker 2: I hope, I think so. Yeah. I mean, even though
Speaker 2: this isn't about fish cuts or fish vomit, I still
Speaker 2: think this.
Speaker 1: Is very cool in a way. It is about fish
Speaker 1: cuts because it's about all of us.
Speaker 2: That's aw man. That was poetic, really poetics modern days.
Speaker 5: Saga over here, all right, all right, thanks everyone for
Speaker 5: going on this journey with us into the dark heart
Speaker 5: of matter and understanding what makes up our uni and
Speaker 5: what we know about it.
Speaker 2: And if you have a question about the universe, you
Speaker 2: can send it to us at Questions at Daniel and
Speaker 2: Kelly dot org. We look forward to hearing from you.
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