 So welcome back everybody to the SMU physics department speaker series for spring 2021. And this is the final event of our academic year, which is dubbed the spring colloquium. And in a moment, I'm going to invite Professor Durdana Balakishiyeva to introduce today's distinguished speaker, Professor Pierre Ramon. But before we get started, I wanted to make some of the usual reminders here. So to our audience on zoom. I just wanted to remind you that to ask a question during or after the talk, you just need to type the word speak in the chat window. We use that as a kind of speaker queue and we'll get to you in the order in which those those requests to speak arise. If you asked to speak during the presentation will interrupt Professor Ramon at the next slide change boundary or thereabouts. Okay. And you'll only be able to speak when called upon by a moderator which I will serve as the moderator so Durdana doesn't have to worry about that for the event. The other thing to know is this event is being recorded on zoom and it's being simultaneously live streamed on YouTube the YouTube live stream is non interactive. But we have a number of participants on the live stream today so to our about half dozen participants on YouTube today welcome. Without further ado, I'm going to now hand things over to Professor Durdana will like to see Eva to introduce today's distinguished speaker Durdana. Thank you very much. It's my honor to introduce Dr Pierre Ramon is a distinguished professor of physics at the University of Florida and a director of the Institute for fundamental theory at University of Florida. I'm a PhD from my alma mater Synerchus University and has held a number of notable positions, including as a postdoctoral fellow at Fermilab used to call be called National Accelerator Laboratory. I'm a senior fellow at Caltech, a member of Institute of advanced study at Princeton University distinguished silence fellow at Calvary Institute for theoretical physics. He is extremely well known for initiating super string theory, generalizing Paul directs work on point like particles into a context of string theory, and he led to the discovery of the two dimensional set up stage of fully four dimensional super symmetric formulation. He's the single author of three physics textbooks, I have them all on quantum field theory physics beyond the standard model, the group theory, his research research has won numerous prizes. There's not too many to, you know, mention all but mostly Oscar clown medal lies my third prize, Danny Hyman prize and most recently in 2020 direct model, direct medal that was issued at ICDP. One of the schools I went to, we're honored to host him. Our dearest Professor Ramon today to speak on unfinished standard model, and I underline unfinished standard model. Okay. Very good. Well, thank you. Thank you very much. Now I have now this distinguished professors to learn how to share slides that unfinished standard model. Yes. Okay, now. So, so what the talk, basically, as I said, was pandemically inspired, because it led me to, I don't know to some, some history to land some historical perspective. And then talk about the standard model, talk about possible completions. And in particular, working detail on the neutrino strategy for trying to understand more about the standard model, which is work. I'm interested in but I, it will basically tell you more or less. Oops, something. Okay. All right. Okay, so this is what, so now we, we are, as I said earlier, into physics, which still lives in a shadow of genius. And, and then Mark 20 said to have said, he's supposed to have said this thing history does not repeat itself, but it sure rhymes. And so, maybe it was, it's not such a bad idea to go back in a little bit in time and see what, what, how, well, how field got to be where it is. In a Newton's century. The one once people understood what Newton had done their application to Newton's laws led them to understand a whole host of phenomena, no matter what they did. They apply Newton's laws just worked. Then, historically, towards the end of that same century electromagnetism came up. With the invention of the voltage cell that you could store it. And you did not have to take your life in your hands to study it. And that led to new physics in the new physics, of course, is embodied by Maxwell's equation, etc. A century later. Oops. Okay, so, okay, so now let's look about. I'm sorry. Look, an Einstein century. Well, that's the century, of course, there's quantum mechanics, there's general activity, but for us, particle physicists, there is the standard model. And then we are left here with something we have no idea what it is, namely, what am I doing. You know, dark matter, this dark matter. What place does it have, we have no idea. All we know so far is that we have things we do not understand. We don't understand quantum mechanics, we know how to use it. We don't understand general activity, we know how to use it. We think we understand the standard model. We have dark matter, we don't know what it is. So it's a time full of questions. The only question is, can any of these questions be answered within one's lifetime? So, the one thing that is very important is the ubiquity of the vacuum. In a century, well, before when Newton was about a child, Descartes' view of the vacuum was a bunch of vortices. Descartes was the big genius of the time. But the vacuum then under Newton basically was full of nothing. And then with Einstein, we know that it's full of quantum. But now I would like to make a pitch for history repeating itself, which is the Brownian motion calculation. The Brownian motion calculation of Einstein and Smoluchowski basically linked a physical phenomenon, namely Brownian motion, to a fundamental insight using statistical mechanics basically. But the thing that happened that was wonderful, Avogadro's number came out. Avogadro's number was just the purview of chemistry. And once this happened, there was a real game changer because all the people who were doubting the kinetic theory and everything, which were many of them, suddenly understood that this was the real thing. And that is where I say that perhaps we have similar problems right now facing us. First problem we have is standard model vacuum. Now the standard model vacuum, we know that in order to make a standard model work, we have to get, there's an order parameter in it. And the, there's something, and out with this order parameter comes out the Higgs part comes the Higgs particle, which is extremely light compared to what its quantum expectations are. And the question is, is that just a defect of the theory, namely we could add more like we could add supersymmetry, we could do all kinds of addenda to the theory, or maybe does it tell us that there is something wrong with our view of space time in terms of the vacuum. That's an open question. And then, of course, it is not too long ago. The question is, is there any cosmological constant, which was obviously zero by from the theoretical standpoint, right. Is there. And I think it's, it's fantastic because the fact that it is there we don't understand we first of all, we're not totally sure whether or not it's the cosmological constant but it looks like it. The question of state looks a lot like it. And I go back to this to Mark Twain. Why, because when the next genius, when, when, when she solves the cosmological constant. The number of the cosmological constant, the physical number in terms of a cookie theory of space time. We will know that that cookie theory of space time will actually be probably has to be taken very seriously. So, there's something wrong with our vision of the vacuum. But we sometimes it works sometimes it doesn't but somehow the standard model, the Higgs, the likeness of the Higgs is really a problem that nobody understands and my my field has gone to a stand still as a result of this. Okay. All right. So let me tell you in what ways they tell you a few details about the standard model. So, you know, it's a theory of strong weak electromagnetic force between Carol laptop and corpse, but it is it's a beautiful quantum field theory, but it is built on flat space time, which is something we don't really know. It's a, you think of the flat space time basically as a phenomenon, phenomenological description. Okay, but built on that it's like building a fantastic building on the swamp, you know. And sometimes something doesn't work out so we don't understand at all what what flat space time is. In fact, we don't understand what space spaces. Now, when I was a child, the standard model, the thing for a quantum field theory was that it had to be renormalizable. And the renormalizability of a field theory meant that it, yes, it blew up at infinity at very in very short distances. But if you put a cut off and the cut off was so far away from the experiment that it didn't really matter. So if you have a logarithmic cut off, and I was taught that basically quantum electrodynamics was good because it was renormalizable, although people like Iraq thought that it was the wrong theory. Okay. And nowadays, the view of this model is exactly the view it's an effective theory. It's just an effective theory. Okay, with a neutral scalar particle, which happens to be much lighter than the cut off energy that's the thing we don't understand. Okay. And the explanation of such a small mass awaits. And the question again, is there super super symmetry would actually alleviate the problem somewhat. But could we does it really necessitate a rethinking of what space time is. That is I say we're beyond my my base scale. But when when in the middle of the pandemic I start thinking about stuff, big, big stuff like this. Those are the kind of questions that come up. However, from the point of view of working on things it works very well. I mean you can for most things you can disregard these things. Okay. So now let's talk about the local symmetries. My local symmetries of the standard model is you three crosses you to cross you one, their global symmetries they could be, which is very unnumbered by the slept on number. There is a, they could be a picture queen symmetry we don't know. Okay, my, I said that because my, my colleagues that's here at Florida is pierce Kiwi, whose life depends on the on the axiom. And it has basically three carol families, which survived 50 years of experimental tests. Okay, and the model is such broad shoulder that it accommodates but does not explain neutrino masses. In other words, you put an addendum. Okay, and you can explain, but the important thing about the standard model. He does not challenge established principles. There is no direct challenges to the basic laws, as we know that. So that makes it very difficult because usually fundamental progress comes up when there is a paradox between between something that works and something that that the fact that it works implies that some cherish principle has to be dropped, something has to be done. And that happens, of course, rarely. And I, but I think this is only for the true genius. You know, we basically understand what it is. Now, let's look at standard model and general activity. Now, the good news is that the, from a standard models point of view, you ask yourself, where's the cutoff coming from, because it's an effective theory with with the cutoff deep in your body. So general activity probably offers such a cutoff. So, you know, certain sense from the point of view of a particle physicist general activity is just just give it gives you a time where you know that perhaps space time will break down. And, and something funny is going to happen. But there is something quite spectacular about the standard model which is not very much mentioned is that there's an absence of car of gravitational car anomaly. The standard model has zero anomalies connected with with the carality, which is quite quite remarkable because it could have could have been different. And we don't understand so that the carol universe which is what the standard model explained, somehow is shielded from these anomalies, even including the gravitational anomaly. And the most remarkable thing, in order to cancel the carol anomaly, you require both carol leptons and quarks. They combine into this. So this is really the first time that leptons and quarks are unified in their in their ability to car to to basically get rid of a car anomaly. That means that the standard model is a shadow of something very deep. Except we don't know what it is. Now what about dark matter. Now, the sad thing about it right now is that the standard model. There's nothing in the standard model that requires dark matter for consistency. So dark matter could be there it could be an add on, but it doesn't challenge any principle. Okay. All right, but we do know that the standard model interacts with dark matter. Why, because gravity, certainly susceptible to dark matter. And through, and then the standard model is susceptible to, to good to gravity. And therefore they're with your amplitudes. And therefore at some level they will have to be interactions that's quantum mechanics coming in there is no choice, except we don't know. So we don't know yet what party with dark matter is, is it just a bunch of new particles like the axiom or some super symmetric thing or is it a game changer. It's something that really changes. You know, we don't know that yet. You know the words from people. There is it on the left hand side of the right hand side of a bunch times equation so to speak. Now, in comes away. Now the gods, the gods come in. So the direct principle of mathematical beauty. And he talks about the by normal, the by model exploration of nature, one experiment and observation, and from the Iraq's point of view, mathematical reasoning. And he talks about simplicity and beauty and simplicity. For him it's Newton's equation. The beauty for him is the special relativity. And I should, I should tell you something very interesting that that and from this point of view you should always look for for beautiful things. Which of course is very weird for a physicist to say that, but then Iraq was certainly a weird physicist. Okay. And one, one of the things, for example, talking about a deep thought talking about this is that Newton's equations are simple. And the question that the Iraq asked himself, if they're so simple, why is the universe so complicated. And, and, and then he says, well, it must be quantum fluctuations. Okay, this this this from maybe 1938. So this is this is the kind of little remark that the gods leave behind. And, and, and now of course it's it's well known people use this all the time. But that was, that was the, the, the complication came from the boundary conditions basically, which can vary. It's kind of remarkable. So I think that simplicity and beauty will will meet at the standard model cut off that will be the point where everything will go. Unfortunately, the standard model cut off is, is not within the reach of experiment. And right now I don't think anybody's smart enough to understand what's going on and we need experiment. Okay. It's a cruel thing about the standard model is that it's weakly coupled and does and the same scale. If you look at 10 to the minus 15 GB. If you look at 100 of the, of the, of the proton, of the extent of the proton, for example, you find that basically all the couplings in the standard model are perturbative. And this is very cruel. This is a very cruel thing for theories, because perturbative theorists can use perturbation theory. They can use a renormalization so they can use. So it gives a field of play to theorists to extrapolate. Okay, using the equations to show the distances, which is quite remarkable. Okay, so you look at the intersection of gauge and you cover couplings in ultraviolet. You find that the in when you go in the ultraviolet, there is a renormalization group equation which which tells you that the, the coupling of the Higgs potential that makes it go up as a go up as a function of field configuration decreases through the relative corrections, unlike the land our pole by the which increases the coupling. And it can cause instability and there's some sort of a plant chimney that appears very, very bizarre thing. Okay, but this is one of the things that people look at. So the bridge to show the distances. We know there's a bridge. We know that theories can go there. We are looking for patterns. Okay. All right. So, the grand unification. So one way of going through this bridge which people following the beautiful work of pati and salam. Okay, was basically that there was a unification of the local symmetries through asymptotic freedom. And that there was a convergence in the ultraviolet of the various companies and that led people to take to look at the symmetries of the standard model and extend to SU five and so 10 is six and other groups. Okay, which had the consequence of very a number violation. Okay, because in a party salon way of looking at it, a laptop the electron was a fourth flavor of course, with that symmetry was broken. So there was in preserve better than my slept on number but basically left on numbers. But proton decay hasn't been seen. So that means that this introduces in those in those ways of doing things that cut off in the ultraviolet. Okay. So we could look at another way, the intersection of the big work and the town left on mass, going in the ultraviolet. The mass of the big work. Okay, case described as have the mass of the epsilon for BB bar compound and threshold. Okay, and experimentally the mass of the big work is about three times the mass of the town left. Okay, but the big work masses we normalized by the strong into by by by QCD to an extent that is not met by the laptop, and you can define a new scale where MB equals empty because MB equals empty is a special scale for the for the SU five theory. So the factor of three from the renormalization group sets another ultraviolet scale. Okay, which would mean that new particles will be required, but then there's something because if you use SU five you get proton decay, and I'll be much, much too fast. So again, we don't know what we do. Now this is I want to make a simple pitch before I turn to the neutrino discovering proton decay. Well if we discover proton decay. We have a bridge to Plunk scale physics. So you don't have to increase the energy. Yeah, use ever God was number made a lot so that was not to get money to define proton decay, the present lifetime of the proton, which in the E plus by not channel is 10 to the 35 years that super come your company has. In the near future, next 10 years, it will be increased to 10 to the 36 years with something called hyper K that can which is more of the same. In the meantime, what do people like me do. Well, we look now for a bridge to the mystery of neutrino masses. Why neutrinos are massive and why are they so light. It's not a very, it's not a very stable bridge yet because we don't know what's going on. So, so now the rest of the talk will be to talk about neutrinos. So, for the first thing about a neutrino, it was, it was not born from experiment directly. It was born in the mind of a theorist. Okay, which may, which means that it was not believed by experimentalist for a long time. It was coming from the south and you guys are in the south too. It was the only elementary particle detected south of the Mason Dixon line at the Hanford reactor in the Georgia South Carolina border. And it was the those were the original particles. And, and when they were followed in retrospect, they always brought new physics with them. In particular, Carl, Carl seem to break it. So it has been a rewarding research area. And now I want you to meet a few of the reward ease. Well, no less than a week for me, we've gone powerly. Leon Lederman, Mel Schwartz and Jack Steinberg who passed away very recently. Okay. And, but there were more. There was Fred, Fred Reines, Ray Davis, Mariko Koshiba, Kajita. And now those two in color just have a line. Okay, so Kajita and McDonald with the last two. But there's another thing about neutrinos. There's something I call the neutrino or other thing. These are people who basically made fundamental contributions but somehow died too soon or, or we're not understood at the time. One of course is my honor. Okay, the answers. The other one is Bruno Ponte Combo and is Maurice Goldhaber. And if you teach a course in experimental physics. Measurement of the spin of the neutrino is probably one of the great gems of experimental physics. To a resonance scattering. It was just one of these incredible things. Then we had Sakata and another great genius. But Carl would die too soon Lincoln Wolfenstein. Those have also died too soon. So let's go to the letter. And I think this is interesting because of sociology. So the famous letter of Paulie. Yes, dear radioactive ladies and gentlemen, blah, blah, blah, anything tells. So you don't have to read the whole thing. You can read it later on. You have a desperate remedy to save the exchange theorem, which was the public exclusion principle. And the, the fact that, and then there was another problem, the energy theorem. And he said they could exist in nuclear electrically neutral particles with spin one half and do not travel with the speed of light. I want you to know this because when you look at the end of the, you know, the summary of it all, it's supposed to be very clear. It was not. And he said, I do not feel secure enough to publish anything about this idea. Only those who wage you can win. And then he says, unfortunately, I cannot appear tubing in because I'm indispensable. You're an account of the ball, etc. Wolfgang Paulie was a strange person. But you see what happened in his mind. The public, the idea of a new particle. Okay, which explains two things was even that he did not write it down. And probably inventing a new particle to explain phenomena was just a, a, not a match or thing to do because the match or thing to do was to explain everything with what you have. Very different from today, when, when, whenever you have something new, you invent. And you know, Paulie's analysis with Carl, Carl, you know, that's true. So Paulie's two problems. The party exclusion principle, which was the following 1930. Yeah, would that be very good the measurements of Roman scattering on the nitrogen nucleus. And, and the not the nitrogen nucleus. This is before Chadwick was made up of we knew how much it weighed. So it has 14 protons and seven electrons because it renew its chemistry and seven electrons. So, somehow those, they had to be, they had to be something different, but that, that, you know, that is, that that is a boson as the line intensities are different from, from, from bosons and fermions. Okay. And then the second part. So this was a problem that people were worried about. The second part was the continuous and continuous energy spectrum of the better decay electron. Okay. And those were the two problems. Well, so he calls it X. And therefore now we have the night. So he looks at, at the equality. Little neutral, by the way. Oh, yeah, little neutral or neutral. I think he called it neutral by itself. Nitrogen nucleus 14.7 electron plus X. And then he added the X in here. And that was it. Now, 1931 Chadwick neutrons of the nitrogen problem because basically the nitrogen nucleus, the atomic weight of 14 is actually seven proton and seven neutrons. So we know it's it's back to the way it is. And the little neutral remains. And in 1939, only 1939 says that Paul is particle is not in the nucleus. It is created in and emitted during better emission. It took 26 years to find it. Okay. And that that was found by All right, that was done by Clyde Cowan and Fred Reines. So first need about, first thing about neutrino physics, you need to live long. So you have to have a certain longevity for neutrinos. Now, the pot, the Ponte Cova brothers. Next. So Bruno is the physicist. Greedo is the biologist. And Jillo is the is the movie guy. He's the one who the battle of our Gears and and again, and 1945 Bruno proposed a ways to detect neutrinos, which you hit neutrinos with with chlorine. You get argon and you get electron Fermi thought it was not practical because every at that time everybody went to Fermi to double check because Fermi was the guru of the time. Okay, but Ponte Cova never published. And the only time I met Ponte Cova, he regretted this very much. And, and he had reprints made of his, of his chalk river preprint. And Ray Davis uses it to count neutrinos from the sun. The same state gold mining lead South Dakota pronounced lead, which is now the site of doing the doing detector, the central doing the detector. And what happened he assembled a bunch of graduate students, and he took out the argon. Okay, because the argon that was produced was radioactive lived only about a month. If you did it quickly enough, you could tell the argon in it. And if you are certain number are gone, and we tell you how many neutrino hits. Okay, you expect and Davis finds one sort of expected rate. There it is. In 87 comes in the supernova and the underground proton detectors that were being built just become these basically neutrino detectors because a trainer of neutrinos was found. Okay, then comes super K. All right, and now super K is a lot of material buried inside a mine except the money is that basically you drive to the mine horizontally because the money is under a giant mountain and you drive into the mountain. Okay, and those neutrinos come from cosmic rays and also from the sun. Okay, and there it is. So the from cosmic rays that the you would find the decay products when the cosmic rays hit the atmosphere. You would find a certain ratio of new to electron neutrino. Well, you find more or less the same. And, and you have the number so you have different type of things. You have neutrinos that come through the earth onto the detectors from neutrinos that come from above. You expected something you expect equal number and you find. And of course, the reason is that these guys were traveling different distances. Therefore, there was different observation. And then there was a Zenith angle dependence. So they discovered two flavor oscillation. And the thing that was remarkable was at the angle that appeared in that oscillation was about 45 degrees. In the process they, they, they, they confirmed, they confirmed the deficit of electron neutrinos that they visit phone and therefore since they oscillate the only that means oscillating from one to the other that means you can distinguish one to the other. And the only label and the only label that was available was basically their mass, because you know in quantum mechanics once you have a label, the label is a dynamical thing. Okay, so next next come another guy the snow detector, which is now this is under a mine in Canada, and, and you look at the theory and you look at the association by neutrinos. All right, and you look at between the electron elastic scattering and sure enough, electron neutrinos oscillate electron neutrino deficit is concerned is confirmed. The solar electron neutrino float is good is confirmed. The angle is not as large as the other one for for this but it is the same and, and the counter, it counts neutrino flavors and the late john Bacall, who basically did not live on long enough to, to be rewarded for this are basically, it was confirmed. And then the large, the last mixing angle. Okay, was basically the so called reactor angle between the three neutrinos. It was first discovered hinted at by, by a reactor at the border between France and Belgium. And then, but it was really with accuracy, it was the first Chinese experiment, or basically, he was, he was, he was, he truly measured the angle with a great deal of accuracy. The Korean detector, we know, found it as well. And what it does is that, basically, these are neutrinos produced in reactors, etc, etc. I mean, they are the question is that you get through a reactor mixing angles, you have an L over a dependence. But in that case, the reactor angles, it's eight and a half degrees. Okay, so what you have is a remarkable thing that basically you have the three mixing angle in a neutrino sector. One of them is of the, you know, it's kind of reminiscent of the quark mixing angles, you know, the quark mixing angles the largest one is the capable and which is about 12 degrees. But the other two are very large. So something is happening, we don't know what. So a little bit of theory. The question is, why are neutrinos so light. Well, let's let me remind you a little bit about the neutrinos, I guess we're running out of time. So, the three neutrinos occur, as the basically are doublets, one for the electron one for the muon, one for the tau. They all have a third component of this weak iso spin under which they are doublet, which is plus one half that's the upper component. You could form for them a Majorana mass, which is neutrino neutrino. But this has the weak iso spin of because this each each neutrino has weak iso spin one half and as everybody knows when you put two, one half together you get either one or zero for the total six. But the statistics work here that you get one. But if you give a left thumb number to the neutrinos, you get two, that would be one kind of mass. But it gets more complicated because you could add a right handed neutrinos. Like for example, the electron is a left handed neutrino, you see the electron that is in a doublet here, that's a left handed electron. But there is a right handed electron so you can do you can add a right handed neutrino which is which has weak iso spin equal to zero, just like the right handed electric electron has also has a spin week equal to say and then you could form what is known as a direct mass, but it has very different quantum numbers. It does not violate the left thumb number, but it violates the week by half a unit. And now come comes the magic of this dirac and my arena unite. Okay, to, to provide an explanation as to why the neutrinos are so light. And, and the basic thing is what my real man called called the stupid little matrix. Basically, what it is is that you, if you take what happens you look at a minor on a mass. And this is a, this, these guys are direct masses, and you don't put the delta I week equals one. Okay, you don't put any, any minor on a mass in there, except for the, for the very heavy for a very heavy one for the right handed neutrinos. And this guy here has basically a, a nugget value m, which is, you see these two, two matrix when you look at the trace of this, of this is M, but the determinant is small m squared. And that means that one mass belongs is like capital M, if maybe m is much larger. And the small last, the other mass is reduced by m squared all right. So it's reduced by the scale of the electric interaction by this unknown scale. And that is the school to see so mechanism will be basically off the by uniting all of the stuff you get, you get very small suppression mechanism. Okay, so that's, that is probably very important. And that the mass, the mass ratio is just the math. So it's so basically I think what happens is that there is a suppression mechanism that comes from the existence of a new mass scale we know nothing about. Okay, that that is really the, as they will say now it is the takeaway. Okay. So, if you took, if you look at the, if you try to explain all of this stuff, this suppression in the most sophisticated way, you've, there is a limit on the mass of the neutrinos which is provided by the Planck survey. And this distance for me electron volts. Okay, and, and that which corresponds in the stuff to about the scale of 10 to the 16 G. Now what is interesting is that that is the scale at which proton decay could become important. So there is a big coin, there is a coincidence that perhaps the scale that appears in a neutrino physics may actually have something to do with a scale close to Planck scale. And this is the dream that particle physicists are living with. Okay. Now, so now let's just go back and look at this neutrino mixing. The name of the leptomixing matrix is called PMS. P is Potecovo, Maki Nakagawa and Sakata. Three Japanese Potecovo with his, with his reactions, it was more like neutrino anti neutrino observations, whereas all of those that have been observed today are neutrino, one flavor of neutrino to another flavor of neutrino. PMS were under the Sakata, Sakata, Sakata. Basically, once they knew there were two types of neutrinos, they started talking about mixing. But okay. And the question is that this object, you PMS, which is measured with those angles are measured, measured in terms of when you look at from a theory standpoint, it's made up of two parts to unitary matrices, one that comes from new physics we know nothing about, and one that comes electro weak physics, okay, the delta is equal to zero. So it means that naively the experimental value of the angles could be basically a small component, because the angles in the quark mixing angles, angles are all very small. So the black one will be small, and then there will be a new angle. So in this, in this, in this view, the two larger neutrino mixing matrix would be a characteristic of a new physics. And for my point of view, again, when I was, when I learned chemistry, large angles met crystals, large angles met crystal faces, you measured angles between crystal faces, etc. Okay, so perhaps there is some sort of structure there, but nobody knows. I mean, I have, I have ideas, of course, but I will not be believed rightfully so, because it's not right. So, let me show you what the present values are. It's like that. Okay. And, okay, so you see this guy here is small. These guys are, you know, this is what we know. Okay. So the quark mixing matrix, let me, I was in two bridges. Okay, so the quark mixing matrix is a beautiful matrix, which has been measured to, but it, but it is the mixing between up quarks and down quarks. Okay, that is the one. And so we know both sides of the bridge. The largest angle there is basically the capitol angle which I says about 12 degrees. Now the left on mixing matrix is that stuff we don't know what the heck it is on the other side. Okay. And so this one take over my key neck. Okay. Yeah, by the way, Ponte Covers brother, the Gido, the, if any of you remember the movie, The Battle of Algiers, which was a very famous movie at some point got an Oscar, etc. Is the is the is the director of that movie. Yeah, so it was a talented family and the older brother was a biologist. Well known actually. Now, so that is truly a bridge to the unknown. So that is, that goes again, that is the kind of, and the good thing that happens. Okay, is that now, since we have the know what else can we do with it. Well, the first thing is that the large angle now for hope to explain the barrier and asymmetry. Now in a cosmology. Okay, the, the, the conventional cosmology is that the universe started being symmetric matter anti matter symmetric. And that the asymmetry that we see today has developed because of various mechanisms. And one which basically prevent, well, some were proposed. But so far, nothing has really been understood. One is that we know that in this case, there is a laptop number, not that this is the total laptop number. There is a phase which is which experiments tell you is non zero. And this, by the way, is a convention that the particle data group uses. And then there are two Majorana's CP violating phases, which we don't know these two experiments are going to be well, doing and and hyper K. Okay, and, and then this neutrino less double beta decay experiment which will be. The graduate students will see it but I will not see them. Okay, they will be so now the question is theoretical challenge and this is the last thing. Now the device. The model that was that we people are playing with is saying that the end we should think of the mixing angles for the leptons as being a beautiful. Like you that that matrix actually was actually proposed by an experimental is called Perkins. So, so then defending myself because it's an experimental. Okay, and then the noise the noise on this. Okay, so so you will have the standard model side will not contribute to that, but it will, it will come it will contribute to filling the zero. Okay, so there will be a Majorana crystal and the cutoff. So is it simple or beautiful we don't know the answer. So, okay, so I think it's, I filled your head. So, when we're finishing a talk like this is that you know I kind of pointed you to, to various directions of this. Okay, but all of them are question marks. I think that is interesting which I did not mention too much is that some experiments right now are going to give us tell us something about the amount of this angle for example it's going to be measured much more carefully. Right now there is a by the Japanese and perhaps do. We'll see. Okay. So, so the idea that direct simple and beautiful maybe there is the neutrinos are trying to tell us there's something fantastic and waiting us. So, now let's turn to practical uses of neutrinos. First use, you don't need to build temples to the sun. We know where the sun is at all times. See, in the, in the old days people used to build these things to make sure that the sun would rise again. Because you know from the beginning, you know the sun disappears, and you never know so that the priesthood became very, very busy, you know, making sure that you know by building is the sun would dain to reappear. But now, I mean physics has taken the magic out of this. The neutrinos are pure everywhere. So, this, this is kind of a useless thing, but nutrient, let me finish with neutrino chronology. So the revelation of a neutrinos 1930. The detection 1956, which is two times 13 years later. The oscillations with a degree of, of, of certainty. This was the, the talk in 1998. Okay, is to do is four times 10 to the seven years later. Okay. And therefore, as my, my own habit as a string theorist, I look at the pattern and I say, well, maybe I should generalize this for the next big experiment. I see two to the first zero to the first, second and third, and then the next prime number is 19. Therefore, that, that will be revealed in 2052. In the meantime, enjoy the starry nights. Okay, thank you very much. Okay, no thank you very much pure and since zoom is so bad at applause. Let's try to give you a little bit of applause here at the end. Thank you. All right. All right, so we've come to the time when we can open up now for questions and I see we already have one question from Pavel Nadolski so Pavel let me go ahead and get you unmuted okay you should be able to unmute leave yourself unmuted until you're satisfied with the answer Okay. Thank you so much for the wonderful. Yeah, hi. So I wanted to ask you. In your opinion, are there viable mechanisms of electric symmetry breaking that do not evolve my around your chinos. So in other words, am I around and she is necessary for breaking electric symmetry. No. No, I mean, the, the order parameter of the electric symmetry is. Well, it depends. I mean, for example, if you want to, you could forget about all this stuff and just look at the Majorana mass for neutrino. Then you need an order parameter that is transformers is ISO triplet. I mean the order parameter of the standard model is an iso double it. But if you put an iso triplet by hand. Okay, then you will you will you will you will introduce a Majorana mass by by its coupling. But the problem now this would be a heaven for experimentalist, because once you do this, the Higgs guys that that that come in other words. The guys that come with the with the six triplet with one of them will have a double electric charge. Okay, so that that's a paradise for experimentalist I mean because then I mean something with with charge to would be a thing but then you have to explain basically why is why is the mass of a neutrino so slow. Okay, now, now Majorana masses are necessary to explain bearing on a symmetry through leptogenesis. I did not have time to go into this. But it is really necessary as his proton decay, you know, Sakharov way of talking about proton decay, which is bearing on a number of violation. Well, that's one, but you see, you know, standard model B minus cell is, is, is left in barrier. So if it's broken, then B, B is broken because B minus cell is in barrier. Okay, so that that is called leptogenesis that comes from the direction. Okay. Thank you. Okay, great. Yeah, no thank you, Pavel. Our next question comes from Tom Cohen, and you should be able to unmute Tom again leave yourself unmuted until you're satisfied with the answer. Yeah, I am kind of I have a kind of provocative question in the in the run up to the LHC. I heard infinite seminars where the statement was made at one TV skill uniterity is violated. The physics is guaranteed to pop up. What's wrong with that statement. Well, what, what, well there are new particles coming in. And they did come in and there is a Higgs particle. There is, you know, all these things are fine. The only problem that's not fine is that the, the mass of the Higgs is, is measured very accurately. In fact, you know, some people have done it. And, but there is nothing, it's a quantum field theory. So it's okay. Unitarity is eventually violated but not at that scale. Yeah, but who was surprised that the Higgs was found. Nobody, nobody was surprised that it was fun, but I, but I, okay, I will tell you that they used to be a time when the Department of Energy and the particle data group was actually handing out one sheet poster on the standard model. Okay. Right. If you look at that. There is no mention of the Higgs. Okay. And the reason is because, even though people like Steve Weinberg and others of course thought the Higgs was there. And certainly Francois Englert and, okay. And basically, a lot of people thought there would be some strong coupling or something that they, you know, et cetera, et cetera. Okay, that there was no, there was no Higgs there. But the Higgs is there. And so, for some reason, even in the, in the, you know, in the 1990s, there were posters. There were, there were official views where the Higgs, there was a whole community of physicists who thought that there was technical, basically to have strong coupling, more strong coupling stuff. And by golly, I mean, totally amazing. As we go deep now, we learned that the couplings are getting weaker. Not stronger. I mean that, and that of course is the magic of asymptotic freedom. Okay, which, which people do not think about before. So the existence of the Higgs is there, it's perfectly okay. Why the heck is it that, is it that mass? And what people thought that if you added supersymmetry, supersymmetric particles, even a given mass range, you will explain why the Higgs would be light. Well, so the first, the second part of the argument is there, the Higgs is relatively light. Okay, but the first part of the argument, there's no trace of supersymmetric particles in that mass range. Not to say it's not going to be there, but if they exist, it is not in that mass range. The one thing that is kind of interesting about the value of the Higgs mass is that if you look, if you look at the Higgs potential, whose vacuum value gives you the Higgs mechanism. That potential, the parameters of that potential vary in its scale. And if you go very deep in the auto valley, there is a region with that value for that value of the Higgs mass, where basically the lambda five fourth coupling goes to zero, which means that you will have a potential without retaining walls, which means it will not be bounded from below. So you have an unstable situation. And that is a mathematical curiosity at the moment. But maybe it's telling us something very deep. That's why I'm, okay, that's about as far as I can go. And in the chat, Roberto Vega commented that presumably this statement about the violating uniterity was under the assumption that the Higgs mass was larger than one TV. Yeah, yeah, right. Yeah, so the statement was either you discovered a Higgs with low mass or new physics had to show in the form of new resonances. Yeah. And then Pavel Madovsky noted that in the run up to the LHC the concern was more about the naturalness of the standard model radiative contributions than about the uniterity of the standard model. And he points out that that concern about the naturalness of the standard model nonetheless still remains to this day. Yeah, it still remains we don't know. But you see what I'm beginning to think about except that nothing really clever to say is that whenever we look at the vacuum. Okay, in the context of the standard model, whatever it is, this is something weird. I mean the cosmological constant. Okay, I mean to say the least, right. Okay, the, the question is that the, it seems to me that, you know, supersymmetry offers a very beautiful way of triggering electrolyte breaking. Okay, but it's still by some score mass squared becomes negative is driven in the infrared towards the negative, but it's still, it's a it's a conventional potential. Okay, so you're using the land out views of things. But the question is that it seems that whenever the vacuum is involved there's something we don't quite understand. I mean, the vacuum, there are lots of vacuum expectation values everywhere. There's something there and I don't know I don't know what it is I mean that that is, you know. All of the experiment is going to be going to teach us something but right now back to the original, the standard model right now does not challenge in an obvious in an obvious way. Any of the fundamentals. Tom, did you have any more to follow up on there. I'll give other people chance. Okay, Richard you have a question go ahead you should be able to unmute. I have a rather silly question. Thank you very much for the stimulating talk. It's really brings forward questions which are deep in my mind, and one of them is the question on time. The physics theory tends to push the energy scale beyond our ability to measure. Is there any reason to believe that time will behave the same way at very high energies. As a variable. It's always factorized right in our. There are other things right. I mean when you look at quantum mechanics. I mean, as you said time is completely different is just a parameter that you put there with Schrodinger equation yes. I mean in fact you don't even need the Schrodinger equation if you're doing quantum information science you just live in here with space and and you plan you know, you have fun with it. But, yeah, and yet there is special relativity, where was all of a sudden time becomes space or space becomes time they become linked. Okay, so I mean that again is beyond my, my, my base scale I mean right now I think you just, you know, use it as a. I mean, time by itself will not be, what is probably important is the sequencing of things, the notion of before and after. But the question of a, of a continuous time. Maybe that only occurs when you have a continuous space coming up. But before, before there was a continuous time between before there was a continuous space, maybe there was still a sequence of events, but it was not necessarily continuous. Okay, but I don't know. I mean, you know, those are, as I said, those are things you know. So, before the pandemic such thoughts, you did it in a shower. Okay, while you were taking a shower in the morning. Sometimes you thought about such such things with the pandemic, you start thinking about such things a lot more often. Okay, so I plead, you know, it's all the fault of the pandemic. Richard did you have anything you wanted to follow up on there. So, I'll assume not unless you say otherwise. Alright, any other questions for Pierre. So, Pierre, can I ask you a question while we're waiting to see if there's any one last question here. So, you mentioned that we still really on the neutrino side of things we still need information from experiments and so and but you also kind of wistfully noted that some of these experiments are likely beyond a single human time horizon at this point. If you could pick any one experiment and say I want to know the answer from that experiment right now, what would it be and what do you what would you then do with that answer. Well, okay. So, realistically, okay, the, we're at the mercy of, you know, let's talk about the LHC for example. And so it could very well be I mean this is not a very clean business but it's it's looking for new particles. Okay, and if it basically with new detectors more computing powers, power, etc. They have the ability to detect some anomalies. I mean they're always anomalies in the data. That's the nature of quantum mechanics to that basically you can get you can resolve all over the place and you don't know. So, but the question that becomes interesting if they detect some of these anomalies are linked to one another. Okay, then of course it becomes interesting. Okay, but now, but if it is there are two game changing things. Okay, in our future. One I think is, is, is, you know, the detection of proton decay. Now, the, as I mentioned in my one of my slides hyper K, I didn't mention hyper K, but hyper K will increase the, the bound by an order of magnitude after many years of running. Okay, that is one thing. And the second one, the second experiment, which will basically tell you whether there's a minor animus or not. Right, is a neutrino S double beta which I hardly mentioned. And the neutrino S double beta decay tell tells you that, you know, it looks like better decay, except there are no, there are no neutrinos. Okay, and that was proposed 1935 by. Anyway, 1935 and, and, you know, nowadays with the experiments are many orders of magnitude away from possible detection, mostly because of the nuclear physics. It looks, it looks like a very complicated, very well processed. But there is one, the one expert. So, so those two experiments, you know, are game changers in the sense that they are attacking the last, the global symmetry of the standard model. You know, you're going to be able, so it challenges. But the one thing that is very, very interesting is the actual measurement of the CP violating phase, the Dirac phase. Okay. And that, that, you know, nowadays there's just a hint for it. And the effect of this on the overall picture of the, of the, of the leptogenesis, what it, what it's called, is just that the mixing angles in a PMS matrix are large. So, even if you, if you have a relatively large angle. Okay. But you have to, to look at its gauging variant effect you have to multiply by the large, the large angles. And therefore it becomes larger. So it has a chance of explaining the, you know, the number of matter minus anti matter per number of photons, right, which is the, the figure of merit. So, but let, let, let us be modest. Let's first hope that this we measure the amount of CP violation accurately in, in, in the lepton mixing. And there's one more thing I did not talk about, which is the hierarchy. There are two competing hierarchies right now. But that looks to me like it's a normal hierarchy where you have two light neutrinos and one heavy one, but anyway, that's the way it goes. So, but other than that, there must be surprises. Interaction with dark matter. Yeah. I mean, you know, dark matter, I mean, we, we, you know, it's there. Yeah. And there's still, and there's now there's seemingly larger, more open question about what the heck's going on with the mu on g minus two, for example, is that Well, that does a number of explanations. There are too many explanations on that one. Okay, because people have been studying that for, for 40 years. Okay, saying that this is the thing and, and what was holding up was the contribution of the strong interaction to the process. And now, of course, but that is simulation. It seems to be converging. So this is this would be maybe the, you know, there's, maybe there's a new particle. As far as the LHCB, I don't know some three point my mind. I don't know it doesn't fit very well with anything I know. beta SLL is that what you're referring to. Yeah, yeah. Yeah, it seems unfortunately trying to put g minus two and beta SLL together gets conflicting. No, no, no, no, but there are theories to do that of course. Oh yeah. This is what theories do, but you know, you just talk about. I don't know. It's also 3.1. I mean, these people did a heroic work going from 2.6 Sigma to 3.1. Yeah. Okay, I mean that that is truly heroic. I mean, and these guys, the G minus two, they, they could really, really be on the version of the discovery. Right. Because they're the level of four. Yes. Yeah. And so, but you know, it's no way to make a business. I mean, to do a business. There are real ways to find a particle for God's sake. For example, yeah. Yeah, for, for example. And so finding a particle indirectly is nice. All right. Our last question will come from Durdana, which I think is beautifully symmetric. So Durdana, why don't you go ahead and ask that question you put in the chat, because it is provocative. Yeah, well, there were times when times when I was very interested in grand unified theory and I was always hoping that there will be a new experimental result that will allow us to figure out what is exactly we're doing wrong that we are struggling to actually have reasonable and practical theory that would unify all four fundamental forces. And then we were sort of hoping that the Lego results will give us some sort of hint to what is going on to be able to at least bring gravity closer to the other three. We're still so far off on that. I'm not sure if things with Lego experiment made things better or worse. So what do you think is the weakest point of the grand unified theory as it stands today that we are in such a deep mess when it comes to it. Well, the problem is the number of parameters. I mean, you see, once, once you have a bigger group, you're increasing the rank, right, as you go, you go beyond the lecture and the, and the patterns are mathematically beautiful. And, but the question is that when we know that the only knowledge we have is the electric model. The standard model. So the path between the original when unified group. And, and, and this and us is that we have many, many scales of symmetry breaking. Okay, so we just have this, the electric symmetry breaking and we don't even understand the mass of the eggs. How it fits in this. Okay, how come it is immune from when you give corrections. Okay, so, so, and now, so you have to multiply this by force. For example, if you take as you find your, you know, as you five is the rank four thing. Okay, so you have, you have to get to it to as you three causes you to cause you one. So you have to. You have to have, in other words, you have to invent the land house language, new order parameters, right, to basically break this more and more. So you introducing more and more. And the one thing that we have found that we're not good at all is breaking symmetries. We know how to parameterize it. I mean, on rare and brought showed us how to do it, and he is. Okay, but the, the questions that we have, we just a parametrization. And we, and so it's all coming down to the vacuum. And I don't know. So, you know, I just thought statistical mechanics, right. So in statistical mechanics you, you have, you have the thermodynamics stuff. You don't have to know thermodynamics. You just do statistical mechanics and you get thermodynamic quantities. Okay. You know, etc, etc. But if you know, so the question I'm asking, for example, this is. It's stupid. If I do a thermodynamics the one weird thing about thermodynamics is entropy. The second law is weird. And it tells you that the entropy can only either stay constant or go one way, not, not both ways. And it's a little bit like time. Time seems to go only one way. So you ask, I mean, this is pandemic. Okay, but I mean, it's crazy. The question is that are now both men and found the answer. It's, there's another line thing with Avogadro numbers of stuff in it. Okay. And then we can use statistics to understand the going one way in terms of, yes, it happens, but highly the notion of highly unlikely. Which is, which is the statistical interpretation. Right. So then the naive thing is that space time should be, you know, flat space time there's something underneath there. We know that it's full of particle antiparticle pairs. Because we know when you calculate our corrections, they work beautifully. You know, until we get to the goddamn Higgs mass. This is where this is where I mean, I'm at the end of my career right so I mean my, I have tenure. I'm okay. My tenure doesn't depend on these things. But the fact is that it's going to be very difficult to, to make a, you know, to make a physical breakthrough. Okay. I remember. German telling me the following stuff. He said, no, this is very hard to make a breakthrough. This was in the, in the 90s. Okay. And I said, why? We said, because we can as a major breakthrough. We were talking about physics. Whereas the people who were born in the 1900s, and we're in the 20s in the 20s, they were there to make breakthroughs, because the breakthrough were happening just like that. Okay. So it is a tremendous amount of luck. You know, after all, you know, spectral spectral lines were there for a long, long time. People need to spectral lines for a long time and then they got so used to it. They didn't think it was anything interesting. So, I don't know. Yeah, yeah, it's a difficult time. It's a difficult time. You know, keep throwing when he was asked about the Lego experiment is that he was disappointed. And, and the people asking why he said, well, because it's consistent with general relativity. Okay, that's a real theory is talking. I mean, of course, he was delighted. But the question is that the experiment did not show any deviation. And that's a problem we live under the shadow of Einstein. Well, I'm not sure if that's a, I'm not sure if that's hopeful or hopeful. The situation is good, but I mean the fact is, usually these people clean up. Yeah, but they are there at times anyway. Okay, maybe we do live now in a new era of problems that see that we're, you know, taking for granted but we'll crack the walnut as it were on what new physics actually is between dark matter neutrino mixing and mass I mean I don't know perhaps we're living in that spectral lines are again. No, but oftentimes, you know, read, read. Martin Klein, Martin Klein, because what what Einstein was very good at was to pick out some something that he was unhappy with. For example, in his paper of the electric effect. He's very unhappy with the fact that there is, there's the wave life wave nature which is the whole 19th century way. Okay, and then, and then matter on the other hand because Einstein studied statistical mechanics like math. And he says, it's all particles. Okay, and yet you have waves, and he puts his finger on it and by the corresponds of the time, he didn't think necessarily that special relativity was such a big deal. But he thought that putting together wave and particle together. Yeah. I'm not sure. I'm not. You still would have the same reasoning. Because he never mentioned plants in the paper. That's true. It's very interesting anyway. So, okay, no. It is. Oh, my goodness. I think I know it to myself. I have a very old, not very old, an 18 year old malt whisky. And I think it's a good time to. Yeah, I think there's no better reason than a good malt whisky. So, here on behalf of the department in our community, I really want to thank you for doing this. So thanks again one more time for this. You're very my fascinating presentation. Yeah, and, yeah, no, thank you. And you have a wonderful evening. Yes. And we'll close out the event. Thanks everybody and have a good evening. Okay. Thank you. Bye bye.