Did CERN just discover a new particle, using penguins?

00:00:06
Speaker 1: He or Hey, did you hear there was a 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? No, it wasn't. Let me guess something in particle physics. Yeah, you got it. Yeah that makes sense. Name a discovery. What's 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. I am or Hammack, cartoonist and the creator of PhD comics. Hi, I'm Daniel. I'm a particle physicist, and I wish I could swim like penguin. Really, they're so elegant underwater. I mean, they're this incredible animal that 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. As your wife approved this wish 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 Explain the Universe, a production of I Heart 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 about, the big questions that are unanswered, and a lot of new stuff out there particle those planets and galaxies and tiny little fluctuations that we have yet to explore. Oh you bet. On this podcast, 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 to 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 CERTAIN just last week with a surprising value, so I got people kind of excited. Yeah, it seems to be a lot of interesting discoveries coming out of physics these days. And these are from the folks at CERTAIN, which are the ones who discovered the Higgs boson, and you who are partly your employers, right, Daniel, that's right. I knew my research at CERTAIN. They don't pay my salary at all, but I do use their collider smash particle 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 like 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 some of the big questions about particle physics. You know, we have like drilled down into the center of the adom and revealed that protons and neutrons are made of quarks and we have 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 a hundred 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 knowing how to make sense of it. So the goal at certain 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, it didn't smash any or crack open any penguins right in this experiment. No penguins were harmed in the making of this podcast, episode four of the experiment it describes, absolutely not. We love penguins. In fact, that's why we name this particular bit of physics after penguins, because they are just so adorable so to be on the podcast, we'll be asking the question, didcern just discover a new particle using penguins? 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 cartoonists 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 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. 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. There's sort of like a Roschach test, you know, look at this squally lines and tell me what you see. So there's one particular sort of famous diagram which one theorist at one point called a penguin diagram because to him it sort of looked like a penguin. Yeah, I wish we could somehow 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. So wait what, No, those are the feet penguin. Where's the head then, well, it's a headless because you cracked it open and your experiment. How's the headless penguin eat raw fish? Then I don't want to know where the fish goes. I don't know. You told me you were the mad scientists here. I'm just podcasting about it. I didn't do this experiment. I have no responsibility for any miss. You only work in the same place, Daniel, and eat lunch with the same physicists, and you know, get paid to the same union feast. They do have a suspicious amount of sushi, that's true. Maybe they're feeding it to the penguins and those chicken wings on Chicken Wings night. Maybe they're not chicken Oh my god. But yeah, this is the 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, certain does a good job of publicizing their discoveries, and there's a lot of pressure leases and a lot of coverage and a lot of articles quoting physicist saying this is really important. And so a bunch of our listeners wrote in and asked us to break it down for them. We heard from Jonathan Tindell, Margie Foster, Shane Barnfield, Kendall Edwards, Heisman, Essen pre End, Shoe pass One, and Vlodomir. 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, how to penguins work? Or we will not take any penguins apart for you. What's their magnetic polarity in the South Pole? A spinning penguin? Alright, 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. 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 the particles have a lot of energy, that 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, So we use the large hage On 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 blow 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. 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 LC 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 have 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. 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, 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, 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 change on collider. And I mean we've already cranked this thing up to eleven. Right, doesn't go any higher, So you need to build a new collider. Have you tried then? I think there's a twelveth setting on that knob, but people are just too afraid. Well, then not gonna 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 slipping all the buttons. I've had some bad fish for lunch and and 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. 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 either. Yeah, 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're bringing home. Everybody believes in your unicorn. But if instead, if you can't find unicorns because they're too slippery or your canvas not good enough for 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. And that's what we're sort of doing here with these really heavy particles. We can't actually make them, but we hope this 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, oh, there is something weird and new and heavy there. But how could you tell Daniel how different unicorns trucks are from a regular horse, because the only difference is the horn. Well, you know, sometimes a unicorn scratches a tree or something. You've got to be clever, you know, you could look for rainbow poop. I hear that tell tale 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, track the fish. You know they're called narwhals, 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 the 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 turn this thing on, find the Higgs boson and then find like fifty five or thousand or whatever new particles that we could study. We haven't found those yet. 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. So take a particle, for example, like a B Mason, which is 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 the 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 be masons and you measure really carefully what they turn into sometimes this, sometimes that's sometimes the other thing, and you compare that to what you predict from your calculations. If there were no other new heavy particles, then maybe you can see some discrepancies. I see all this time since the Higgs boson, you've been running the LC smashing particles hopefully not birds, and just kind of scene of things. Check out, you know, if they match what your theory says that 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 ways 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 calculations by like adding a new particle or a new force or you know, 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 masons and they didn't look quite right, and we thought, 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 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 it. Is it tantalizing result or is it like a conclusive, wow, we found something results. It's decidedly right in the middle or right it's in a superposition of 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. Right it could be the unicorn, or it could just be a donkey maybe wandering through the forest. Yeah, or like fifteen 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. All right, we're talking about whether or not sar and found a new particle. Is it a new particle or a new force? Daniel, Well, we don't know. I don't know. It's a new thing. It's a new thing. It's a new thing. To not say what the thing is. It might be any 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 as specific a handle on it as if you actually made the thing directly and could see it. De kay, all right, we'll step us through. What did they actually find and what did they measure? So this comes from an awesome experiment. It's called LHC B and it's called lc BE because it runs at the LHC and involves mostly these B corks. Now, BE corks are the pair of top corks. Right, So we have six corks in the standard model. There's the up and the down. These are the ones that are familiar to you because they make you up there in the protons and neutrons. And there's a couple of weirder corks, 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 the Fermi lab in the bottom cork discovered in the seventies. But as usual, there's a controversy about what the call this particle. The bottom cork. Half of the community calls it the bottom cork as a 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 corks. Wait, there's a controversy in the physics community about what to name these particles, and it's been going on for twenty five 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 corks. 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 use beauty and some Europeans use bottom. You just call them beautiful bottoms. Why not. I like big corks, and I cannot lie you go, you can be totally non pc about the part goes in the standard model. Yeah, And so l ah c B is an experiment that's dedicated to studying this kind of cork, the bottom cork, the be corry, the beauty cork, whatever you wanna call it. And it works kind of differently from the other experiments. The one that I work on Atlas, for example, it's sort of like a big cylinder. It surrounds the collision point and takes a picture of everything and 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, is 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 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, kay, watch them do their thing. Well, but this one is different, you're saying, Yeah, So that's how this one is different. At LEAs and cms like surround the collision point, this one 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 principles still applied. They can still 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 Higgs boson or do we make a new heavy particle, But they're looking to identify particles that have be corks 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 be masons or these be corks. You're just interested in watching them decay. So they're made in the collider, but then you sort of catch them where you channel them and then you measure them. Yeah, exactly, So we're interested in this case in this particle called a B plus mason. Remember that quirks can combine in all sorts of ways, but they have these weird things called color, 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. 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 mason. It has two quarks, So you start with an up cork. I mean, you have an anti beauty cork. I don't know what that is, like an ugly cork combined to make this particle called a B plus mason. So it's got two corks inside of it. So you're making pairs of corks, and you call those B plus masons 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 flyouts crazy energy, and the corks gathered 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 masons 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 kon and then two muans or a kon and two electrons. And we think that that should happened exactly the same rate that the universe shouldn't perform. U wants two 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 mun or why would the universe be exactly the same for both. We don't know, and we don't even know why the muon exists. But the ELECTRONO muan 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 then, Muan is basically just a slightly heavier version of the electron. And in every other experiment we see, the universe treats these leptons, the electron, the muan, and the taw all the same. For example, the z boson, which is a very important particle, decays into these things in the case into each 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're gonna have an electron, you can also have a muan, and the same thing happens at the same rate. And so it would be interesting and weird in a surprise if this B plus Mason like to dedicate the muans more often, or like to decay to electrons more often. 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 in the math involved, that 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. And those listeners who are really in the particle physics will know that the ELECTRONO muant are not exactly the same, right. The difference between them is the mass. The mulant 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 of which this thing turns into mus and turns into electrons. And what they're looking for is something more than that, a bigger difference than that. So, yes, our calculations predict that there should be a very very small, almost negligible difference between the rate of decay to muans and two electrons. And then we do the experiment and we measure very carefully to see how often we see one versus the other they 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 Masons 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 Masons, maybe one of them will decay in this way by going to a kayon and a couple of lectons. So you've gotta 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 you know rate. Compare meals on the lecrons coming out. Yeah, and this is where the penguins come in. If you draw the diagram for a B plus Mazon decaying to a kon and two left ons, then you make this series of lines that describe like where the corks go and what's interacting with what, And it sort of looks a little bit like a penguin is at the top of the penguin is at the bottom of the penguin. I'm not exactly sure anymore, but it's a little penguin. Let's just say Daniel did as a cartoonist, as a you know, professional and expert opinion, this looks nothing like about Okay, I will defer to your expert opinion on this one. But the way it starts out, you have a B plus mason, which is an upcork and an anti bottom and then that anti bottom cork changes, it changes to an anti strange cork. So when you get out of the end is an up cork and an anti strange cork, which is how you make the K plus Mazon. So B plus turns into a K plus. But you can't just turn an anti B cork into an anti escort. 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 upen and inside their stuff is happening, and that's where the calculation is or like how often do these little particles shoot off and let this happen? What happens to those particles, why do they sometimes turn into a pair of muance 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? White test this one? Well, there was a whole argument between the penguin community and the eagle community, and that's whole different kind of diagram that people wanted to test. You have an animal name for each diagram? 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. It was just like a simple cross check, because that would be like more of a surprise, is 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 it's simpler interaction, like hey, you know, an electron hitting up a positron or something something more basics, something more basic, it would be more interesting 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, but 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 stack 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 Hey. So people have very specific ideas for what new particles there might be 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 the other ones that involved be masons. And that's why we have this whole experiment LHCb dedicated just to study in the decays of particles that have be corks 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 us, Like why this particular one, the supposedly penguin Lincoln 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 turned into this weird new particle called a lepto cork. Lepto cork 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 model in our theory physics for the relationship between quirks and leptons. Like we see there are six corks. We see there are six leftons. There's a lot of obvious similarities. Leptons are like electrons, right right, electrons, muans, 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, like an intermediary particle, like a link in the evolutionary change. Yeah, the missing link particle, something that's half unicorn half penguin. Again, there's already waiting for you, ding it. Somebody took that parking spot already. And so people have this idea that maybe the b cork instead of just turning into a strange cork via the interactions we know, these penguin dinagram might instead create this lepto cork. This is this new particle because bees are sort of at the border there, or because this is kind of a reaction that involves both leptons and courts. It involves both leptons and quirks. And this is not the only place you might see lepto corks. We might, for example, create them directly at the Large Hadron Collider and we study them. We 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 lepto corks is to let them influence the way the bees decay. Maybe they play a role in how these bees turned into leptons. And they might prefer muans versus electrons. Because these lepto corks might for example, only talk to muans, are only talk to electrons, they might not be willing to interact with the other one. And so it would make sense if these things sort of like broke this lepton universality, if they preferred one kind of left onto another. 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. All right, So, Danny, you're smashing particles at the large Hattern collider. On every two million collisions or every two million times that you make one of these pairs of cords, sometimes they go into electrons and sometimes they become muans, And that's what you're measuring, right, Like how often that one and two million interaction becomes a pair of electrons or para 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, 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 expected to be. Yeah, we expected them to be equal if the standard model is correct. But we did some early measurements, preliminary studies on a small amount of data, and things didn't look balanced. It looked like they were preferring one to the other. Specifically, it looks like it was preferring electrons to muans, Like electron the case were happening more often than muans. So everybody got really excited and thought, oh, maybe this is real. Let's do a really careful study and will analyze our full data set, will 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, 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 gonna 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. 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 knob because there's almost always some way to twiddle the knobs to get an interesting result, because if you do enough experiments, is 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, so we don't actually know what they mean, and we develop our analysis strategies and all the tools and all the programs that we double check them, across check them, and we don't like reveal what those random numbers are until the very end, until 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 see the corruption. 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 are 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. So it's important to institute these controls because remember, of 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 another. 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. No way you can buy them with a fish or two. Man. The guys are cheap, They have no integrity, bad math in penguins. Today you're killing penguins and insulting them all in the same experiment then, and I'm using them to learn about the universe. Your craving nous knows no statistical bount so they made this measurement and they got the number, and the result is something like point eight four point eight four four exactly. What this is the ratio between the muans and the electrons. So what this means is that if you have a thousand decays and go to electrons, you only have eight hundred and forty five they go to muans. And that sounds like a pretty big discrepancy. This is much bigger than I thought. I thought we were going to be seeing something like and we're gonna be wondering if it really is close to one. But this thing is like pretty far from balanced, Like point eight four 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, and the theory says they should be very very close to the same, very very close to one. 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 muans or the fact that the muan 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 lept On Universality, because everything else has been removed. But instead we see it's like eighty five percent instead of one, and so that's a pretty big difference. You said the words leapt On Universality. What does that mean is that like the Dipton University or it's a different campus lept On Universality. That's just a way of saying that the universe treats the electrons and the muans and the towels the same way. You know, it's democratic that 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 uncertainty these 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, and the experiment you do that has quantum fluctuations and it can in principle 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 point eight five. So you can do the statistical calculation and ask how often does that happen? And in particle physics we tend to translate that into units of sigma, like how far from the Gaussian mean are you? And in this case there are about three sigma away, which is pretty good. It means it's like one and one thousand chance of the answer actually being one and having just like weird fluctuations conspire to give them this result. So it's the three sigma I know is pretty good, but like this gold standard's supposed to be five sigma. Gold standard is five stigma. We have this word in particle physics for discovery, and you can't write a paper with discovery in it unless you have five stigma. If you have four sigma, you can call it observation. If you have 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 cattle 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 stigma because you might think, well, isn't one in 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 the large aging collider. It's not the only measurement made at this experiment. It's not the only measurement made with B plus masons at this experiment. So if you do a thousand experiments, each of which have different statistical fluctuations, then you would expect that one out of those thousands we give you a false positive, even if those false positives have a one in 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. Remember when people thought we had neutrinos going faster than the speed of light. A lot more people remember that then 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 five stigma. One in a hundred thousand 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 either something going on here, 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 the masons are transforming into a lepto quark before they transform into the other particles. Yeah, so this 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, 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 actually does agree because this new result is within air borros 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 will 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. I think either different kind of chocolate, and I think that really affects their poop. 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 lepto corks. Yeah, the more exciting possibility is that this is a hint of something new. This is what we've been waiting for the large age on 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. It could be that this is the sign of a lepto corep. 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 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. 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 run but we'll find out. I think that these guys have done it very careful analysis. I know these physicists and our colleagues, and some of them my friends. They know what they're doing. Way I thought you didn't know them, Daniel. Now they're you're best friends. They're on a different experiment, but you know, certain is a very friendly place. Wasted in the cafeteria and eat ice cream and talk about whatever. And also people move from the experiment to experiments. So some of the folks on led c B used to work on Atlas or in a pre this experiment with me. The tight community, so we all do know each other. You just place yourself on the PETA target list there, Daniel, 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 Muan g Mind is too result that came out just afterwards, because the theoretical reference numbers are better understood here, and there are other results from beak work studies that give similar hints that something fishy is going on with these penguin. The case, all right, we'll 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 certain and to see the world of physics giving us hints about how the universe actually works. 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. I hope that was interesting and do 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 I Heart Radio or more podcast from my Heart Radio. Visit the I Heart Radio Apple Apple Podcasts, or wherever you listen to your favorite shows.