Daniel and Kelly’s Extraordinary Universe - Did CERN just discover a new particle, using penguins?

Episode Date: April 20, 2021

Daniel and Jorge explain the exciting new results from the LHCb experiment! Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information....

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Starting point is 00:00:00 This is an I-Heart podcast. December 29th, 1975, LaGuardia Airport. The holiday rush, parents hauling luggage, kids gripping their new Christmas toys. Then, everything changed. There's been a bombing at the TWA terminal. Just a chaotic, chaotic scene. In its wake, a new kind of enemy emerged, terrorism. Listen to the new season of Law and Order Criminal Justice System
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Starting point is 00:02:07 chance for people to unpack and get beyond race. All the Smoke featuring Michelle Obama. To hear this podcast and more, open your free iHeartRadio app. Search all the smoke and listen now. Big discovery, and it involved the word penguins. I didn't. Was it at the South Pole? Actually, it wasn't. Was it about actual penguins? Not that either. Was it even about birds?
Starting point is 00:02:39 No, it wasn't. Let me guess. Something in particle physics. Yeah, you got it. Yeah, that makes sense. Name a discovery with a name that has absolutely nothing to do with the actual discovery. But penguins is just so much fun to say. Yeah, they're fun to look at, too. They're pretty cute birds.
Starting point is 00:02:57 Hi, I'm a cartoonist and the creator of Ph.D. Comics. Hi, I'm Daniel. I'm a particle physicist and I wish I could swim like a penguin. Really? They're so elegant underwater. I mean, they're this incredible animal. They just like waddle around so awkwardly on land. But then you see them in the water and they look like birds, right? They fly through the water the way other birds fly through the air. It's gorgeous. Yeah, but then you have to walk like a penguin on land. Has your wife approved this wishful fulfillment? Well, I wear a tuxedo around the house all the time just to sort of like break it in. Yeah, and you eat raw fish too. But anyways, welcome to our podcast, Daniel and Jorge
Starting point is 00:03:45 Explain the Universe, a production of IHeard Radio. In which we waddle our way around the unknown mysteries of the universe, trying to figure out what they mean. We talk about the craziest little particles. We talk about the things in deepest space. We talk about the hottest things and the coldest things and everything in between because this podcast is all about explaining the entire universe to you. That's right because there is a lot out there to discover and to explore. There are many unknowns that we still don't know anything about, a lot of big questions that are unanswered and a lot of new stuff out there, particles, planets and galaxies and tiny little fluctuations that we have yet to explore. Oh, you bet. On this podcast, we
Starting point is 00:04:25 We think that we are at the beginning of our discovery of the nature of the universe. We think that most of the road, most of the big ideas about the way the universe works are in the future. And we just hope to stick around and be here when some of those big ideas are revealed. So we get to figure out how the universe actually works. Yeah, because there are people working on this. They're called physicists and they're trying every day to figure out what we're all made of and how it all works. And recently there has been some pretty exciting results coming out of the physics community. That's right. There was a big result announced at CERN just last week with a surprising value. So got people kind of excited.
Starting point is 00:05:02 Yeah, it seems to be a lot of interesting discoveries coming out of physics these days. And these are from the folks at CERN, which are the ones who discovered the Higgs boson and who are partly your employers, right, Daniel? That's right. I do my research at CERN. They don't pay my salary at all, but I do use their collider, smash particles together and try to figure out what the smallest thing is. but CERN is host to lots of different kinds of experiments. The kind that I work on smash two protons together and look for new heavy particles, today we'll be hearing about a different kind of experiment at CERN using the same accelerator. Yeah, it may involve maybe a new particle. It may involve a new particle. You know, the fever dream of CERN is to discover all sorts of new particles to crack open
Starting point is 00:05:43 some of the big questions about particle physics. You know, we have like drilled down into the center of the atom and revealed that protons and neutrons are made of quarks and we have a little. electrons whizzing around them, but there are so many open questions about these particles. There's so many particles we don't understand and we don't understand why we have the number we do and why they do the things we do. And we feel like we're sort of in the dark ages of particle physics where people will look back in 100 years and think, oh my gosh, it was so obvious what was going on. But here we are today sort of clueless on the forefront of human ignorance, not really
Starting point is 00:06:15 knowing how to make sense of it. So the goal at CERN is to find a bunch of new particles to sort of fill in the gaps and give us the bigger picture so we can get a sense for like what's going on. Yeah. And today's discovery that we're going to talk about involves penguins somehow. And just to be clear to our listeners, Daniel, he didn't smash any or crack open any penguins, right, in this experiment. No penguins were harmed in the making of this podcast episode or of the experiment it describes. Absolutely not. We love penguins. In fact, that's why we named this particular bit of physics after penguins because they are just so adorable. So today on the podcast, we'll be asking the question. Did CERN just discover a new particle using penguins?
Starting point is 00:06:59 I'm picturing Daniel, penguins wearing white lap coats, standing around some giant machine, pressing buttons, checking clipboards. Am I right? Well, I'm not surprised. That does sound like a cartoonist's view of the penguin particle collider. That sounds like a far side strip. No, not at all. The way it involves penguins is really just,
Starting point is 00:07:17 fanciful. You know, when we talk about how particles interact with each other, we draw these little diagrams that have lines and the lines connect where the particles interact and they diverge when the particles go in different directions. And you can make these diagrams simple for a simple interaction or complicated for like lots of particles interacting. And so you have these abstract sort of diagrams to represent something physical and you can look at them and sort of like see something in them. They're sort of like a Rorschach test, you know, look at this squiggly lines and tell me what you see. So there's one particular sort of famous diagram, which one theory is at one point called a penguin diagram because to him it sort of looked like a penguin. Yeah, I wish we could somehow
Starting point is 00:07:54 show this image to our listeners over this podcast because I can sort of see it maybe. It looks sort of like a square with a little round bottom and two little feet maybe. Is that kind of what they were thinking about? Oh, I think those feet are supposed to be the beak. I think that's supposed to be the face. Wait, what? No, those are the feet. It's it upside down penguin. Where's a head then? Well, it's a headless penguin because you cracked it open in your experiment. How does a headless penguin eat raw fish then? I don't want to know where the fish goes. I don't know. You told me you're the mad scientist here. I'm just podcasting about it. I didn't do this experiment. I have no responsibility for any mistreatment. You only work in the same place, Daniel,
Starting point is 00:08:32 and eat lunch with the same physicists and, you know, get paid to the same union fees. They do have a suspicious amount of sushi. Hmm, that's true. Maybe they're feeding it to the penguins. Yeah. And those chicken wings on chicken wings night? Maybe they're not chicken. Oh my God. But yeah, this is a news that came out recently and several listeners sent in the question asking us to explain it and to talk about what happened and what did they discover. Yes, CERN does a good job of publicizing their discoveries and there's a lot of press releases and a lot of coverage and a lot of articles quoting physicists saying, this is really important. And so a bunch of our listeners wrote in and asked us to break it down for them.
Starting point is 00:09:09 We heard from Jonathan Tyndell, Margie Foster, Shane Barnfield, Kendall Edwards, Heist Van Essendez. Pryanshu Paswan and Vlodemir. So thanks to everybody who wrote to us and asked us to break down this big discovery. We're very excited to talk about it. And if you hear something in the world of physics that you don't understand, please write to us. We will take it apart for you. Yeah.
Starting point is 00:09:30 How do penguins work? We will not take any penguins apart for you. What's their magnetic polarity in the South Pole? A spinning penguin. All right. So these are some new results coming out of CERN. And it involves also the large Hadron Collider, right? It does involve the Large Hadron Collider.
Starting point is 00:09:45 This is our big tool for discovering new physics because it's the way that we can give a lot of energy to these particles. And when particles have a lot of energy, they let us access other kinds of particles that normally we can't see because there's not enough energy around to make them. Remember that in the early universe, things were hot and dense. There was much more energy sort of per area, per volume. And so a lot of these particles probably existed back then. But these days, the universe is sort of cold and slow and separated. And so to create these weird particles to find them, to give us clues as to how to crack the big mysteries of particle physics, we have to recreate those conditions. We have to create a lot of energy density.
Starting point is 00:10:23 So we use the large Hadron Collider to smash protons together to make that little blob of energy, which can give us a clue about what's going on. Yeah, because from that blob of energy, basically anything that can come out does come out eventually, right? With some sort of probability. Like from that blob of energy, other particles can come out. and that sort of tells us what kinds of particles the universe can make. Yeah, exactly. It's sort of amazing. You don't have to know what you're going to make before you turn on the collider.
Starting point is 00:10:49 You just get to see like everything that's possible. And so you just got to sort of watch and eventually everything will pop out. And the classic way to use the LHC to discover new particles is to do exactly that to like make some new particle and then see it turn into something else. And that's what we did, for example, with the Higgs boson. We had to crank up the energy of the particle collider. so there was enough energy to make Higgs bosons and then we could see them turn into other stuff and observe them in our detectors.
Starting point is 00:11:15 That's sort of the classic way. That's the direct way. Like actually make it in your colliders, like have it appear and be visible to your detectors. But that's sort of difficult because then you actually have to have enough energy to create these things. Yeah.
Starting point is 00:11:27 And so this new discovery uses sort of a different way of discovering particles, right? You're looking not at actually making the particles you're looking for, but looking at their effects on other particles. Yeah, we are limited. by the energy we can pour into the collider. And so, for example, if there's another particle that's just a little bit too heavy for us to make it,
Starting point is 00:11:47 then we can't make it in the collider. It just doesn't appear when we make those collisions. And so that really limits our ability to find these things because it's not easy to crank up the energy of the collider. To do that, you need like a bigger ring, which means a bigger tunnel or stronger magnets. All that stuff is expensive and very hard to change. It's not like there's just like a knob on the large adjunct collider. And I mean, we've already cranked this thing up to 11, right? It doesn't go any higher.
Starting point is 00:12:10 So you need to build a new collider. Have you tried, though, Daniel? I bet there's a 12 setting on that knob, but people are just too afraid. Well, they're not going to let me in the control room because I love to twiddle knobs and press buttons. And so I'd go crazy in there. You're like a penguin, just slapping all the buttons. I've had some bad fish for lunch and I'm making some bad decisions. But there is this other trick we can use that you just mentioned to try to see hints from other particles.
Starting point is 00:12:34 Because if you create the right conditions, these other big, heavy particles that you don't have enough energy to actually make, they can still influence what's going on. They can, like, appear momentarily. They can, like, pop out of the vacuum and nudge some of the particles we can see and then disappear again. Yeah. And so that tells you about that particle, right? You see the effect of it. And so you can say, hey, is that something new there? Yeah.
Starting point is 00:12:58 It's sort of like if you go to the forest and look for unicorns, the best thing to do is to, like, see a unicorn, right? Okay, you got a unicorn, you bring it home. Everybody believes in your unicorn. But if instead, if you can't find unicorns because they're too slippery or your camera's not good enough or whatever, you might find evidence of unicorns. Maybe you see their tracks or you see how they're like, are bothering the other horses or something. It's more indirect, but you can convince yourselves that those unicorns exist without actually seeing one.
Starting point is 00:13:25 And that's what we're sort of doing here with these really heavy particles. We can't actually make them, but we hope they sort of appear in these fluctuations and affect the particles that we can see. And if we measure those effects really precisely, then we can deduce that, ooh, there is something weird and new and heavy there. But how could you tell, Daniel, how different a unicorns tracks are from a regular horse?
Starting point is 00:13:45 Because the only difference is the horn. Well, you know, sometimes a unicorn scratches a tree or something. You got to be clever. Or, you know, you could look for rainbow poop. I hear that telltale sign of unicorns. Yeah, exactly. I heard that sometimes penguins ride unicorns also. So you could just like look for the penguins or, you know,
Starting point is 00:14:03 track the fish. You know, they're called Norwell's, Daniel. But that's exactly it. It takes an extra cleverness. You have to, like, find a way that these new particles might affect the particles you are looking at in a unique way, in a way that you can't explain any other way. And then you have to make really, really precise measurements of the particles that you're studying. And so because at the LHC, we haven't found any new particles, you know, we were hoping when we turned this thing on, find the Higgs boson, and then find, like, 55 or 1,000 or whatever new particles that we could study. We haven't found those yet.
Starting point is 00:14:35 It's been a bit disappointing. And so our backup plan sort of is to find hints of these new particles to reassure us that they are there, even if they're above our energy range. I see. Because somehow, even if you're not creating the necessary amount of energy, they could still somehow pop up or still somehow kind of affect the probabilities of the other particles? What sort of effect are we talking about? Well, we're talking about how particles decay.
Starting point is 00:15:01 So take a particle, for example, like a B-Mazon, which is a, a combination of two weird corks. These particles decay, and when they decay, they do it by interacting with W bosons and Z bosons and other particles. So you draw a lot of these lines that describe how the particles decay. But if there are other ways for them to decay, if they can decay by interacting with these new weird, heavy particles, then that will change how often they decay and what they decay into. So if you take, for example, these B mesons and you measure really carefully what they turn into, sometimes this, sometimes that, sometimes the other thing. And you compare that to what you predict from your calculations, if there were no other new heavy particles,
Starting point is 00:15:38 then maybe you can see some discrepancies. I see. All this time since the Higgs boson, you've been running the LHC, smashing particles, hopefully not birds, and just kind of see things. Check out. You know, if they match what your theory says you should see. Yeah, that's a good way to put it. One way to find new particles is to like actually see them. The other way is to look for little discrepancies. Like, is there anything weird in the data at all? Anything we don't understand because we can do these careful comparisons and anything that doesn't match up indicates that there's something new, there's something we didn't expect, something exists in reality that doesn't exist in our calculations, which means we need to change our
Starting point is 00:16:15 calculations by like adding a new particle or a new force or a new tiny little bird that's affecting the experiments. All right. And apparently you have found some sort of weird anomaly in the data, right? Yeah. Until recently, there were some hints. There were some things that were sort of tantalizing, but not really significant enough to make anybody believe they meant anything. We were looking at the decay rates of these B mesons, and they didn't look quite right. And we thought, hmm, maybe there are some new particles, but you need really precise measurements. And, you know, we saw things decaying in one way, and they were expected to decay another way, but they were kind of close also. And we spent a lot of time assessing the uncertainties on these
Starting point is 00:16:54 things to see, like, do they overlap or not? And so there were some hints, but they weren't really conclusive. And so people thought of a more precise way, a more powerful way to test these things. And that's the result that was released just last week. It's pretty significant, you think? Is it tantalizing result or is it like a conclusive, wow, we found something result? It's decidedly right in the middle. It's in a super position of both exciting and boring at the same time. Yeah, exactly. We will look back later and know whether this was the first hint of a crazy new discovery that revolutionized physics or it's just another blip that turned out to be nothing. We will know in the future. Right now we don't know, but we can have fun speculating.
Starting point is 00:17:34 Right. It could be the unicorn or it could just be a donkey, maybe, wandering through the forest. Yeah, or like 15 penguins in a trench coat, you know. Any of those would be exciting, especially to the donkey. All right, well, let's get into what they actually found and measured and discovered and what it all means. But first, let's take a quick break. December 29th, 1975, LaGuardia Airport. The holiday rush, parents hauling luggage, kids gripping their new Christmas toys. Then, at 6.33 p.m., everything changed. There's been a bombing at the TWA terminal.
Starting point is 00:18:19 Apparently, the explosion actually impelled metal, glass. The injured were being loaded into ambulances, just a chaotic, chaos. scene. In its wake, a new kind of enemy emerged, and it was here to stay. Terrorism. Law and Order Criminal Justice System is back. In season two, we're turning our focus to a threat that hides in plain sight. That's harder to predict and even harder to stop. Listen to the new season of Law and Order Criminal Justice System on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. I'm Dr. Joy Harden Bradford, and in session 421 of Therapy for Black Girls, I sit down with Dr. Afea and Billy Shaka to explore how our hair connects to our identity, mental health, and the ways we heal.
Starting point is 00:19:14 Because I think hair is a complex language system, right, in terms of it can tell how old you are, your marital status, where you're from, you're a spiritual belief. But I think with social media, there's like a hyperfixation and observation of, you know, of our hair, right? That this is sometimes the first thing someone sees when we make a post or a reel is how our hair is styled. We talk about the important role hairstylist play in our community, the pressure to always look put together, and how breaking up with perfection can actually free us. Plus, if you're someone who gets anxious about flying, don't miss session 418 with Dr. Angela
Starting point is 00:19:52 Neil Barnett, where we dive into managing flight anxiety. Listen to Therapy for Black Girls on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. Get fired up, y'all. Season two of Good Game with Sarah Spain is underway. We just welcomed one of my favorite people and an incomparable soccer icon, Megan Rapino, to the show. And we had a blast. We talked about her recent 40th birthday celebrations, co-hosting a podcast with her fiancé Sue Bird, watching former teammates retire and more.
Starting point is 00:20:22 Never a dull moment with Pino. listen. What do you miss the most about being a pro athlete? The final. The final. And the locker room. I really, really, like, you just, you can't replicate, you can't get back. Showing up to locker room every morning just to shit talk. We've got more incredible guests like the legendary Candace Parker and college superstar A. Z. Fudd. I mean, seriously, y'all, the guest list is absolutely stacked for season two. And, you know, we're always going to keep you up to speed on all the news and happenings around the women's sports world. as well. So make sure you listen to Good Game with Sarah Spain on the IHeart Radio app, Apple
Starting point is 00:20:59 podcasts, or wherever you get your podcasts. Presented by Capital One, founding partner of IHeart Women's Sports. I'm Dr. Scott Barry Kaufman, host of the Psychology Podcast. Here's a clip from an upcoming conversation about exploring human potential. I was going to schools to try to teach kids these skills, and I get eye rolling from teachers or I get students who would be like, it's easier to punch someone in the face. When you think about emotional, regulation like you're not going to choose an adapted strategy which is more effortful to use unless you think there's a good outcome as a result of it if it's going to be beneficial to you because it's easy to say like like go you go blank yourself right it's easy it's easy to just
Starting point is 00:21:40 drink the extra beer it's easy to ignore to suppress seeing a colleague who's bothering you and just like walk the other way avoidance is easier ignoring is easier denials easier drinking is easier yelling screaming is easy complex problems problem solving, meditating, you know, takes effort. Listen to the psychology podcast on the IHeartRadio app, Apple Podcasts, or wherever you get your podcasts. All right, we're talking about whether or not CERN found a new particle. Is it a new particle or a new force, Daniel? Well, we don't know. We don't know. It's a new thing. It's a new thing. It's a new thing. It's the new thing. It's the new thing. It's the new thing.
Starting point is 00:22:25 to not say what the thing is. It might be anything. We just don't know. One of the disadvantages of discovering something this way is that you don't really know what's causing it. You see something weird. It might be evidence that there's something new, but you don't have a specific handle on it as if you actually made the thing directly and could see a decay.
Starting point is 00:22:44 All right. Well, step us through. What did they actually find? And what did they measure? So this comes from an awesome experiment. It's called LHCB. And it's called LHCB because it runs at the LHC and it involves most of the these B corks. Now, B corks are the pair of top corks, right? So we have six corks in the
Starting point is 00:23:01 standard model. There's the up and the down. These are the ones that are familiar to you because they make you up. They're in protons and neutrons. Then there's a couple of weirder quarks, the charm and the strange cork, which are a little bit heavier and it can make funny little particles. And then the last generation, the last pairing are the bottom cork and the top cork. Top cork only discovered in 1995 at Fermilab and the bottom cork discovered in the 70s. But as usual, there's a controversy about what to call this particle, the bottom cork. Half of the community calls it the bottom cork as member of the pair top and bottom. The other half of the community calls it the beauty cork because they call them the truth and the beauty quarks. Wait,
Starting point is 00:23:40 there's a controversy in the physics community about what to name these particles and it's been going on for 25 years. Is that what you're saying? Yeah, they just don't know how to make these decisions. There are some people who measure these things being produced and they call them bottoms. And the other community, the one studying how these things decay, tend to call them beauty quarks. And those two are sort of different communities and they don't get together that often. And so they've just sort of like gone their own ways, calling the same particle with two different names. Is it like a Europe versus U.S. thing? No, not even. I think maybe there's more Europeans saying beauty and more Americans saying bottom. But there's definitely some Americans I've heard
Starting point is 00:24:16 use beauty and some Europeans use bottom. You just call them beautiful bottoms. Why not? I like big quarks. I cannot lie. Yeah, there you go. You can be totally non-PC about the particles in the standard model. Yeah, and so LHCB is an experiment that's dedicated to studying this kind of cork, the bottom cork, the B cork, the beauty cork, whatever you want to call it. And it works kind of differently from the other experiments.
Starting point is 00:24:41 The one that I work on Atlas, for example, is sort of like a big cylinder. It surrounds the collision point and takes a picture of everything that flies out because we're hoping to make something at that collision and then see what it turns into. This experiment is a little bit different. There's still a collision point. You're still colliding protons on protons. They're not interested in what happens in the actual collision. They're interested in what happens to the stuff that flies out. Because when you have these protons colliding, you also get like a huge shower just sort of like junk particles out the front. And because there's a lot of energy coming in both directions and most of it just sort of like
Starting point is 00:25:13 goes down the beam pipe. So this experiment is different because it doesn't surround the whole collision point with detectors. It just captures some of that forward stuff and looks for these bottom corks and watch them turn into other stuff. Watch them interact. Watch them decay. Watch them do their thing. Cool. But this one's different, you're saying. Yeah, so that's how this one is different. Atlas and CMS, like surround the collision point. This one's just sort of like forward stuff, like the stuff that spews out towards the beam pipe. It takes a picture of that. And so it's organized kind of differently. But the basics principle still apply. They can still like find the tracks of particles. They can still measure their energies. But what they're looking for is not like, did we make a new
Starting point is 00:25:49 Hays boson or do we make a new heavy particle, but they're looking to identify particles that have b quarks in them and watch those particles decay. But you're still watching the collisions, though, right? These things are created from the collisions, but they're sort of like secondary products of the collisions rather than the primary products. You don't really care what created these B mesons or these b quarks. You're just interested in watching them decay. So they're made in the collider, but then you sort of catch them or you channel them and then you measure them. Yeah, exactly. So we're interested in this case, in this a particle called a B plus Maison. Remember that quarks can combine in all sorts of ways,
Starting point is 00:26:25 but they have these weird things called color. And sort of the analogy of electric charge for the strong force, the strong nuclear force. If you want to have a particle that doesn't have an overall strong nuclear charge, we call that without color, then you need to have the colors balance. So you can do that by having one cork and an anti-cork, where the cork is like red and anti-red or green and anti-green.
Starting point is 00:26:47 You can also do it by making triplets of these particles. like a proton or a neutron has three quarks inside. This particle we're discussing is a B plus mazon. It has two quarks. So you start with an up quark. And then you have an anti-beauty cork. I don't know what that is like an ugly quark. Combined to make this particle called a B plus mazon.
Starting point is 00:27:06 So it's got two corks inside of it. So you're making pairs of quarks and you call those B plus mesons because they're a different combination of corks and then you study what happens to those. Yeah. When you have the original collision from the proton, all these corks fly out. this crazy energy and then the quarks gather together into particles because they don't like to be by themselves. If you're interested in that, we have a whole fun podcast episode about why quarks can't be alone because the strong nuclear charge is so weird. But yeah, you're right. We have these B plus
Starting point is 00:27:33 mesons that are made and then we watch and see what happens. And so in particular here, they're watching to see if these particles decay into a caon and then two muons or a caon and two electrons. And we think that that should happen exactly the same rate, that the universe shouldn't prefer muons to electrons, that the rate at which these two things happen should be exactly equal. Because electrons have the same, I don't know, energy as a muon, or why would the universe be exactly the same for both?
Starting point is 00:28:03 We don't know, and we don't even know why the muon exists. But the electron and muon are very, very similar. They're almost exactly the same particle. They have the same electric charge. They interact with the weak force the same way. They're basically cousins, right? The muon is basically just a slightly, heavier version of the electron. And in every other experiment we see, the universe treats these
Starting point is 00:28:23 leptons, the electron, the muon, and the tau, all the same. For example, the Z boson, which is a very important particle, decays into these things and decays into each at almost exactly the same rate. So we don't know why, but we have observed everywhere else in particle physics that these things are treated universally. That everywhere you can have an electron, you can also have a muon, and the same thing happens at the same rate. And so it would be interesting and weird and a surprise if this B plus Maison like to decay to muons more often or like to decay to electrons more often,
Starting point is 00:28:56 that would show a weird preference for one kind of particle over the other and maybe a hint that something new is going on. Because the theory says that they should be the same, like the math involved as they should be exactly, or at least the math that you have, says that you should see the same results equally. Yes, the math that we have says that should be almost exactly equal.
Starting point is 00:29:15 Now, those listeners who are really into particle physics will know that the electron and muon are not exactly the same, right? The difference between them is the mass. The muon is heavier than the electron. And that does make some difference. But they account for this in their measurements, and they know how much the mass should affect the rate at which this thing turns into muons and turns into electrons. And what they're looking for is something more than that, a bigger difference than that.
Starting point is 00:29:38 So yes, our calculations predict that there should be a very, very small, almost negligible difference between the rate of decay to muons and two electrons. And then we do the experiment and we measure very carefully to see how often we see one versus the other. I see. And you're checking to see if the two are different by that small amount or if they're different by more or less than what the theory predicts. Yeah. And the thing that we're looking for is pretty rare. Like it's not like B plus mesons like to decay in this way. This is not of like a happy way for them to decay. This is very weird. Like if you have two million of these B plus mesons, maybe one of them, will decay in this way by going to a caon and a couple of leptons.
Starting point is 00:30:16 So you've got to make a lot of these things because it's very rare anyway. It's like a rare combination for it to decay into. But if it happens, it should happen at a certain rate compare mons and electrons coming out. Yeah. And this is where the penguins come in. If you draw the diagram for a B plus mazon decaying to a caon and two leptons, then you make this series of lines that describe like where the quarks go and what's interacting with what. and it sort of looks a little bit like a penguin.
Starting point is 00:30:44 Is it the top of the penguin? Is it the bottom of the penguin? I'm not exactly sure anymore, but it's a little penguin-y. Let's just say, Daniel, that as a cartoonist, as a professional and expert opinion, this looks nothing like a penguin. Okay. I will defer to your expert opinion on this one. But the way it starts out, you have a B-plus Mazon, which is an up quark and an
Starting point is 00:31:03 anti-bottom, and then that anti-bottom quark changes. It changes to an anti-strange quark. So the way you get out at the end is an up-cork and an anti-strandom. strange quark, which is how you make the K plus meson. So B plus turns into a K plus. But you can't just turn an anti B cork into an anti S cork. That's just like changing the flavor of it. When you do that, you have to like shoot off another little particle. So you get this little loop which makes it happen. And inside there, stuff is happening. And that's where the calculation is. They're like, how often do these little particles shoot off and let this happen? What happens to those particles?
Starting point is 00:31:36 Why do they sometimes turn into a pair of muons and sometimes turn into a pair of electrons? And that's where all the sort of nasty, gory theoretical calculations have to happen. I guess maybe one question is, why did you pick this particular diagram and interaction to probe or to double check that it's doing what the theory says? You know, aren't there like a million or maybe infinite number of interactions that could happen in a particle collision? Why test this one? Well, there was a whole argument between the penguin community and the eagle community. That's a whole different kind of diagram that people would. wanted to test. Wait, do you have an animal name for each diagram?
Starting point is 00:32:09 No, I just totally made that up. No, that's a good question. Why do we choose this specific diagram? Well, the truth is, we would be happy to see deviations anywhere. And personally, I would prefer to see deviations, not where we expect, not where we're looking in the place where we expected to see no deviations. That was just like a simple cross-check, because that would be like more of a surprise. That would be like, huh, you weren't even thinking about finding a deviation here, and here it is. And that's the kind of discovery I'm hoping for, one that like really rocks the foundations of physics and makes us rethink everything. You mean like a simpler interaction like hey, you know, an electron hitting up a positron or something, something more basic. Something more
Starting point is 00:32:45 basic. That would be more interesting to you. Or even just something we didn't expect because, you know, there's a lot of theorists out there who have ideas for what new particles there might be. We go to the Large Hadron Collider and we can create whatever is out there. We also like to have an idea for what we might create. It makes it more powerful to find it. It is easier to see something if you know to look for it than if you don't, right? If you're looking through a sack of hay and you know you're looking for a needle, it's easier than if you're just looking for anything that's not hay. So people have very specific ideas for what new particles there might be
Starting point is 00:33:17 and where we might see them. And so this is a very rich area of research where lots of people have come up with new ideas for why we might see particles in this particular decay. And also in some of the other ones that involve bee mesons. And that's why we have this whole experiment, LHCB, dedicated just to study in these. decays of particles that have bee quarks in them because people have identified lots of these weird decays that might give us clues about new particles that are out there. Well, can you explain it for
Starting point is 00:33:44 us? Like why this particular one, this supposedly penguin-looking one, why this one might be especially useful for finding new particles? Yeah, sure. And the reason that bees are exciting is that they have sort of a lot of mass. They are heavier particles than the other ones. And that just gives them more options. Like when they're decaying, there's more stuff that they can turn into because they're heavier. They have like a bigger budget for what they can do. And one thing they might do, for example, is turn into this weird new particle called a leptocork. A leptocork quark is a particle that can talk to corks and it can talk to leptons. And that's very unusual because most of the particles can either just talk to corks or to leptons. And like we don't have an idea in the standard
Starting point is 00:34:26 model in our theory of physics for the relationship between corks and leptons. Like we see there six corks, we see there are six leptons. There's a lot of obvious similarities. Leptones are like electrons, right? Right. Electrons, muons, tows, and all the neutrinos. There's six of those and there's six of the corks. And there's a lot of obvious parallels and similarities between these two sets of particles, but according to our theory, they're totally different. And so it would be exciting if we found a new particle that was sort of like a combination of a cork and a lepton. It would tell us something about how these two very different kinds of particles are connected. It would give us a clue to, like, put these two things together in the same context.
Starting point is 00:35:06 Like an intermediary particle, like a link in the evolutionary chain. Yeah, the missing link particle, something that's half unicorn, half penguin. Again, Norwell, Daniel. Sorry. There's already a name waiting for you. Dang it. Somebody took that parking spot already. And so people have this idea that maybe the b quark instead of just turning into a strange quark via the interactions we know,
Starting point is 00:35:27 these penguin diagrams, might instead create this leptocork. This is this new particle. Because bees are sort of at the border there? Or because this is a kind of a reaction that involves both leptons and quarks? It involves both leptons and quarks. And this is not the only place you might see leptocorks. We might, for example, create them directly at the large hadron collider. And we've studied them.
Starting point is 00:35:49 We've looked for them. I actually worked on exactly that research for a while. But we don't have enough energy to see them if they do exist. So this is like another way to maybe see hints of leptocorks is to let them influence the way the bees decay. Maybe they play a role in how these bees turn into leptons. And they might prefer muons versus electrons because these leptocorks might, for example, only talk to muons or only talk to electrons. They might not be willing to interact with the other one. And so it would make sense if these things were like broke this lepton universality. If they preferred one kind of lepton to another.
Starting point is 00:36:23 All right. Well, let's get into a little bit more detail of what they actually measured and what it could mean and whether or not it's a statistical fluke or maybe actual unicorn poop. But first, let's take another quick break. December 29th, 1975, LaGuardia Airport. The holiday rush, parents hauling luggage, kids gripping their new Christmas toys. Then, at 6.33 p.m., everything changed. There's been a bombing at the TWA terminal.
Starting point is 00:37:03 Apparently, the explosion actually impelled metal glass. The injured were being loaded into ambulances, just a chaotic, chaotic scene. In its wake, a new kind of enemy emerged, and it was here to stay. Terrorism. Law and order, criminal justice system is back. In season two, we're turning our focus to a threat that. hides in plain sight. That's harder to predict and even harder to stop. Listen to the new season of Law and Order Criminal Justice System on the IHeart Radio app, Apple Podcasts, or wherever you get
Starting point is 00:37:41 your podcasts. I'm Dr. Joy Harden Bradford, and in session 421 of therapy for black girls, I sit down with Dr. Ophia and Billy Shaka to explore how our hair connects to our identity, mental health, and the ways we heal. Because I think hair is a complex language system, right, in terms of it can tell how old you are, your marital status, where you're from, you're a spiritual belief. But I think with social media,
Starting point is 00:38:10 there's like a hyper fixation and observation of our hair. Right, that this is sometimes the first thing someone sees when we make a post or a reel is how our hair is styled. We talk about the important role hairstyles play in our community. The pressure to always look
Starting point is 00:38:26 put together and how breaking up with perfection can actually free us. Plus, if you're someone who gets anxious about flying, don't miss Session 418 with Dr. Angela Neil Barnett, where we dive into managing flight anxiety. Listen to Therapy for Black Girls on the iHeartRadio app, Apple Podcasts, or wherever you get your podcast. Get fired up, y'all.
Starting point is 00:38:48 Season 2 of Good Game with Sarah Spain is underway. We just welcomed one of my favorite people and an incomparable soccer icon, Megan Rapino, to the show. and we had a blast. We talked about her recent 40th birthday celebrations, co-hosting a podcast with her fiancé Sue Bird, watching former teammates retire and more.
Starting point is 00:39:07 Never a dull moment with Pino. Take a listen. What do you miss the most about being a pro athlete? The final. The final. And the locker room. I really, really, like, you just, you can't replicate,
Starting point is 00:39:19 you can't get back. Showing up to locker room every morning just to shit talk. We've got more incredible guests like the legendary Candace Parker and college superstar AZ Fudd. I mean, seriously, y'all. The guest list is absolutely stacked for season two. And, you know, we're always going to keep you up to speed
Starting point is 00:39:37 on all the news and happenings around the women's sports world as well. So make sure you listen to Good Game with Sarah Spain on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. Presented by Capital One, founding partner of IHeart Women's Sports. I'm Dr. Scott Barry Kaufman, host of the Psychology Podcast. Here's a clip from an upcoming. conversation about exploring human potential. I was going to schools to try to teach kids these skills, and I get eye rolling from teachers
Starting point is 00:40:04 or I get students who would be like, it's easier to punch someone in the face. When you think about emotion regulation, like, you're not going to choose an adaptive strategy, which is more effortful to use unless you think there's a good outcome as a result of it, if it's going to be beneficial to you. Because it's easy to say like, go you, go blank yourself, right? It's easy. It's easy to just drink the extra beer. It's easy to ignore to suppress seeing a colleague who's bothering you and just like walk the other way avoidance is easier ignoring is easier denial is easier drinking is easier yelling screaming is easy complex problem solving meditating you know takes effort listen to the psychology podcast on the iheart radio app
Starting point is 00:40:47 apple podcasts or wherever you get your podcasts All right, so, Daniel, you're smashing particles at the Large Hadron Collider. And every two million collisions, or every two million times that you make one of these pairs of corks, sometimes they go into electrons and sometimes they become muons. And that's what you're measuring, right? Like how often that one in two million interaction becomes a pair of electrons or a pair of muons? And so what did they find? So they had hints for a while that maybe things weren't looking like they were going to be equal.
Starting point is 00:41:25 but they didn't really have enough data. You don't expect them to be equal, right? You're just checking to see that the difference is what you expect it to be. Yeah. We expected them to be equal if the standard model is correct, but we did some early measurements and some preliminary studies on a small amount of data and things didn't look balanced. It looked like they were preferring one to the other.
Starting point is 00:41:44 Specifically, it looks like it was preferring electrons to muons, like electron decays were happening more often than muons. So everybody got really excited and thought, oh, maybe this is real. Let's do a really careful study. and we'll analyze our full dataset, we'll use every collision that we can and we'll get a really precise result. And when you do this, you have to be really careful not to introduce bias into your answer. There's lots of different ways to analyze these collisions, to look at the data that's coming out.
Starting point is 00:42:09 And if you know what the answer might be, you might be tempted to, you know, like bias it, not in a conscious way, not in a way where you're like, I'm going to make up some false data. But if you have to make a choice between one way of doing things, another way of doing things, you might, you know, prefer to do one way if it leads to an exciting result. You might twiddle the knobs until you see what you want to see. Yeah. And what we want to do is measure how likely this is to be a random fluctuation. And so to do that, we need to make sure not to twiddle the knobs because there's almost
Starting point is 00:42:38 always some way to twiddle the knobs to get an interesting result because if you do enough experiments, there's always one that's weird. And so we want to make sure to be unbiased so that we're like really knowing whether what we see is real. And to do that, we institute a bunch of controls to make sure. that nobody is accidentally subconsciously twiddling those knobs. And the way we do it is we make the data analysis blind. So we like add a big random number to every collision.
Starting point is 00:43:03 So we don't actually know what they mean. And we develop our analysis strategies and all the tools and all the programs. And we double check them and cross check them. And we don't like reveal what those random numbers are until the very end, until we're 100% sure we know what we're doing. So it makes for like a big reveal at the end. So it's almost like you corrupt the data on purpose. So that like what you see is not actually anything, but then at the end, you take out that plant, that seed, that corruption.
Starting point is 00:43:30 Yeah, it's like we're working with encrypted data. And then we type in the password and it all becomes clear at the end. And that prevents us from like sculpting the data or making choices that might lead us down one path or the other. And this can go in two directions, you know. It can be biased towards repeating the results of previous experiments because like, hey, those folks measured this thing. We should probably get a number that agrees. And it could also be biased towards seeing something new. like, who I want to find something new and win a Nobel Prize.
Starting point is 00:43:56 So it's important to institute these controls because, remember, science is done by people and people make mistakes and people have biases. And even if they're not actively trying to corrupt these analyses, and nobody here is, of course, they can subconsciously make choices that lead in one direction or the other. So we protect against that by sort of blinding them from the data. But I thought the experiment was being done by Penguin. Everyone knows they're totally impartial.
Starting point is 00:44:18 No way. You can buy them with a fish or two, man. These guys are cheap. They have no integrity. Oh, man. I'm bad-mouthed penguins today. You're killing penguins and insulting them all in the same experiment, Daniel. And I'm using them to learn about the universe.
Starting point is 00:44:34 Your cravenness knows no statistical bounce. So they made this measurement, and they got the number, and the result is something like 0.84. Wait, 0.84? Exactly. What? This is the ratio between the muons and the electrons. So what this means is that if you have... a thousand decays that go to electrons, you only have 845 to go to muons. And that sounds like
Starting point is 00:44:58 a pretty big discrepancy. This is much bigger than I thought. I thought we're going to be seeing something like, you know, 95, 98, and we're going to be wondering if it really is close to one. But this thing is like pretty far from balanced. Like 0.84 is pretty far away. And the uncertainties on that are pretty small. They're pretty confident this isn't just a statistical fluctuation. I see. But I thought you were expecting there to be not the same. Or, Are you saying that you were expecting them to be the same? Or the theory says they should be the same? The theory says they should be very, very close to the same, very, very close to one.
Starting point is 00:45:31 And we do a bunch of stuff to remove any other sort of biases, like the way that we see electrons versus the way we see muons or the fact that the muon is slightly heavier by doing a double ratio with another pair of decays that helps protect against making sure that there's no biases. So we would expect this number to be exactly one if there was lepton universality because everything else has been removed. But instead, we see it's like 8.
Starting point is 00:45:53 25% instead of one. So that's a pretty big difference. You just said the words lepton universality. What does that mean? Is that like Lipton University? It's a different campus. Lepton universality, that's just a way of saying that the universe treats the electrons and the muons and the tau's the same way. You know, it's democratic.
Starting point is 00:46:11 These particles should all appear at the same rate when you have a particle decaying. So that's what we're testing. So then you measure these outcomes, electrons versus muons, and you found that one comes out more than the other, which could mean something and is it pretty conclusive or are you still sort of in the initial stages where it could maybe be a statistical fluke? It could still be a statistical fluke and there's a lot of discussion about exactly what it means. You know, they spent a lot of time doing a very careful analysis of the uncertainties and they can measure how likely they are to see a result this far from one if it was just a random chance. You know, because things do happen that are random.
Starting point is 00:46:48 Any experiment you do that has quantum fluctuations in it can in principle, will give you any answer. It's like having a room full of monkeys. If you have enough monkeys and you let them go for long enough, eventually one of them will start a podcast or type out Hamlet or whatever, right? And so what you want to do is measure how likely is it for the real answer to be one, but then for random fluctuations to give you an answer that looks like 0.85. So you can do the statistical calculation and ask how often does that happen. And in particle physics, we tend to translate that to units of sigma, like how far from the Gaussian mean are you? And in this case, they're about three sigma away, which is pretty good.
Starting point is 00:47:26 It means it's like one in one thousand chance of the answer actually being one and having just like weird fluctuations conspire to give them this result. So it's, then three sigma I know is pretty good, but like this gold standard, it's supposed to be five sigma, right? Gold standard is five sigma. We have this word in particle physics for discovery. And you can't write a paper with discovery. in it unless you have five sigma. If you have four sigma, you can call it observation. If you have
Starting point is 00:47:54 three sigma, you can call it evidence. So there's all these words that translate the number of sigma into the words that you can use. And six sigma is like, holy cow, or oh my God, or it is the unicorn poop. And there's a reason that we are skeptical that we have this standard of five sigma because you might think, well, isn't one and a thousand good enough? Like that seems like pretty unlikely that this is a fluctuation. The problem is that we do a lot of experiments. This is not the only measurement we've made to the Large Hadron Collider. It's not the only measurement made at this experiment. It's not the only measurement made with B plus mesons at this experiment. So if you do a thousand experiments, each of which have different statistical fluctuations,
Starting point is 00:48:35 then you would expect that one out of those thousands would give you a false positive, even if those false positives have a one and a thousand chance of happening. If you do enough experiments, you will see these rare false positives. And we do a lot. And also, you're making big claims about the universe, so you want to be super extra sure. One in a thousand is not good enough to challenge our view of the universe. Yeah, and particle physics tends to be very, very conservative about making claims. They would rather wait and make the discovery in an extra couple of years or when they have more data than make a false discovery and claim to discover something and then have it not be true because people remember that. You remember when people thought we had new
Starting point is 00:49:14 is going faster than the speed of light. A lot more people remember that than basically anything else we've discovered because that was a big embarrassment. And so we try to be very conservative and wait until we're really pretty sure. That's why we have this kind of arbitrary standard of 5 Sigma 1 in 100,000 chance of a fluctuation before we sort of officially believe something. All right. So you found something that might be possibly something that tells you there's something going on here.
Starting point is 00:49:38 It's not what the standard model predicts in physics. And so what's the view of what could be happening? Like you mentioned that maybe these B-Masons are transforming into a leptocork before they transform into the other particles. Yeah. So there's sort of the spectrum of possibilities from the most boring to the craziest. The most boring explanation for this is that somebody's made a mistake, you know, that it's just wrong somewhere that they forgot to account for something or they're not seeing something right. And so the best way to check that is to do a completely different experiment at a different accelerator using a different detector and a different group of people. And so there's a Japanese experiment that's running, and they will give us a totally independent measurement of exactly the same effect.
Starting point is 00:50:21 And since it's in the same universe, it should be the same number if they did it correctly. And so currently the results from the Japanese experiment don't agree with these results. Their number is like, you know, close to one, but it has a really big error bar. So it actually does agree because this new result is within the error bars of the old one. But the old one sees something a little bit larger than one. So the most boring answer is somebody made a mistake, it'll get resolved in a few years when they do more careful experiments. Well, I think the problem is probably that, you know, unicorns in Japan, they do tend to be a little bit different than unicorns in Switzerland. They eat a different kind of chocolate and I think that really affects their poop.
Starting point is 00:50:58 No, I'm just kidding. All right. So then what's the exciting possibilities that the particles are transforming into these new kinds of particles called leptochorks? Yeah, the more exciting possibility is that this is a hint of something new. This is what we've been waiting for, the Large Hageon Collider. We've been hoping to find some new physics, some clue that tells us the secrets of the universe that helps us understand how all these particles fit together to explain the fundamental nature of matter. And so this could be that moment that cracks it open.
Starting point is 00:51:24 It could be that this is the sign of a leptocorp. But you know, there's lots of other people out there with other ideas for new particles that could explain this. One problem with this discovery, again, is that we don't know exactly what it is. It's sort of indirect. So we can't see this new particle and like measure its mass and see what it turns. turns into and see what it interacts with. We're only seeing like the scratches on the trees and the shape of the footprints in the ground.
Starting point is 00:51:48 We're not actually seeing the thing directly. So it opens the door for lots of fun ideas and I expect to see lots of cool papers with exciting new theoretical ideas on the web in the next few days as people get their like intellectual juices flowing about what could explain this. All right. I guess stay tuned. Maybe this is the first hint of something that cracks open, the standard model and hints at new unicorn particles, or maybe Daniel just press the wrong button. We'll find out.
Starting point is 00:52:16 I think that these guys have done a very careful analysis. I know these physicists. They're my colleagues and some of them are my friends. They know what they're doing. Wait, I thought you didn't know them, Daniel. Now they're your best friends. They're on a different experiment. But, you know, CERN is a very friendly place. We sit in the cafeteria and eat ice cream and talk about whatever. And also people move from experiment to experiment to experiment. So some of the folks on LHCB used to work on Atlas or on a previous experiment with me. It's a tight community. So we all do know each other. You just placed yourself on the PETA target list there, Daniel.
Starting point is 00:52:44 Uh-oh. For experimenting with penguins. Only virtual penguins, particle physics penguins. But I have a lot of faith in these guys. I think that this experimental result is probably correct. I just don't know what it means. And I think it's more exciting than the muon G-minus 2 result that came out just afterwards because the theoretical reference numbers are better understood here.
Starting point is 00:53:04 And there are other results from B-Cork studies that give similar hints that something fishy is going on with these penguin decays. All right, well, stay tuned. Then we'll wait to see what other people say about it, whether it confirms or whether it points to something else going on. Yeah, and it's exciting to see some new results coming out from Surin and to see the world of physics giving us hints about how the universe actually works.
Starting point is 00:53:28 And if you see a study out there that you'd like to understand better, please send it to us. We would love to break it down and explain the universe to you. We hope that was interesting and you enjoyed that. Thanks for joining us. See you next time. Thanks for listening and remember that Daniel and Jorge Explain the Universe is a production of iHeartRadio. For more podcasts from iHeartRadio, visit the iHeartRadio app, Apple Podcasts, or wherever you listen to your favorite shows.
Starting point is 00:54:10 December 29th, 1975, LaGuardia Airport. The holiday rush, parents hauling luggage, kids gripping their new Christmas toys. Then, everything changed. There's been a bombing at the TWA terminal, just a chaotic, chaotic scene. In its wake, a new kind of enemy emerged, terrorism. Listen to the new season of Law and Or. order criminal justice system on the iHeart radio app apple podcasts or wherever you get your podcasts get your podcasts get fired up y'all season two of good game with sarah spain is underway
Starting point is 00:54:53 we just welcomed one of my favorite people and incomparable soccer icon megan ripino to the show and we had a blast take a listen sue and i were like riding the lime bikes the other day and we're like we're like people ride bikes because it's fun we We got more incredible guests like Megan in store, plus news of the day and more. So make sure you listen to Good Game with Sarah Spain on the IHeartRadio app, Apple Podcasts, or wherever you get your podcasts. Brought to you by Novartis, founding partner of IHeart Women's Sports Network. Tune in to All the Smoke Podcast, where Matt and Stacks sit down with former first lady, Michelle Obama. Folks find it hard to hate up close.
Starting point is 00:55:35 And when you get to know people and you're sitting in their kitchen tables and they're talking like we're talking. You know, you hear our story, how we grew up, how Barack grew up, and you get a chance for people to unpack and get beyond race. All the Smoke featuring Michelle Obama. To hear this podcast and more, open your free IHeart Radio app. Search All the Smoke and listen now. This is an IHeart podcast.

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