Angels & Demons: The Science Revealed

so welcome my name is Bob Jacobson I'm here from the physics department to introduce Joel as you've seen from the movie how many of you actually read this book okay I'm gonna try really hard not to give it away any clear plot points but this movie involves a certain amount of dispute between scientists and the Vatican and I won't tell you who wins but but one of the key parts of it is scientific research that's done at a place called CERN building something that is going to be used to do detriment to the Vatican and Joe will tell you more about this we take this in a very white hearted spirit you know scientists have have been in conflict with other cultures even in this campus forever do you know who this campus is named for Bishop Berkeley you know what he's famous for proving that the calculus was wrong so we got even with that although it took 180 years to finally do it he also was a philosopher but that doesn't count tonight so we view this in a certain light-hearted way as part of that we have brought t-shirts because we're going to adapt you to our culture and and because I'm a physicist I probably can't throw these that far it's really tough to get a spiral out of a t-shirt you got two more to go there's no way I can get you that far away okay that's it for that if you brought a car if you got a card and you brought it Maria is the person to give it to she's waving a card right here and Joel is his actually works in this Joel works in the production and antihydrogen he has for a while this is an ongoing project it's won a wonderful piece of science he has to leave tomorrow morning to go to CERN which is in Switzerland to work on it so thank you we thank him in advance for spending his evening with us telling us all about him well thank you very much I'm sorry about us getting started late I've we set up a large number well a few demos here and they've taken a little bit of time to get running I think I'm a little bit too loud at the moment so no okay it sounds too loud up here anyway okay as Bob just mentioned the book Angels & Demons movie Angels & Demons is based on this book by Dan Brown and the most I'm going to give away of the plot in a big way is that the plot is that a secret society called the Illuminati steal about a quarter of a gram of antimatter from the CERN Physics Laboratory in Geneva Switzerland for use in a plot to blow up the Vatican unfortunately for us Sony Pictures has been kind enough to provide us with a clip which explains all of the physics behind this which I'm going to play for you this what this is quite quiet so I'm going to turn the volume up where is that camera number 86 it's wireless it too was stolen he could be anywhere inside of anything that canister contains the extremely combustible substance called antimatter we need to locate it immediately or evacuate Vatican City I'm quite familiar with incendiary swiss veteran I've never heard of antimatter being used as such well it's never been generated in significant quantities before it's a way of studying the origins of the universe to try to isolate what some people call the god particle but there are implications for energy particle what they call it isn't important it's what gives all matter mass the thing without which we could not exist you're talking about the moment of creation yes ma'am the antimatter is suspended there in an airtight nano composite shell with electromagnets on each end but if it were to fall out of suspension and come in contact with matter say the bottom of the canister then the two opposing forces would annihilate one another violently now what might cause it to fall out a suspension if I are you going dude which it will in six hours of a kind of annihilation how violent a cataclysmic event a blinding explosion equivalent to about five kilo times Vatican City will be consumed by light at that I hope you understood that because to tell you the truth I haven't a clue what they were talking about all right that's not really true I do understand some of this stuff a physicist and Nobel prize-winning physicist named Leon Lederman decided to call a particle known to physics as the Higgs boson he decided to call it the god particle well actually he didn't his publisher did he wanted to call it the goddamn particle which got censored but you have to agree that they have different implications nonetheless the god particle got taken up by the media physicists hate it we've refused to acknowledge it but there it is the Higgs particle or the Higgs boson was proposed by Peter Higgs and others back in the 60s and the Higgs is the only as yet unobserved particle in the standard model of particle physics it's a very important particle because it's this particle which is thought to give mass for all of the other particles we've got electrons protons neutrons and so on and so forth but we don't have any fundamental understanding of where their mass kind comes from in fact they all scale off of this Higgs particle and if we could discover the Higgs particle we would be able to predict what the mass of all of these particles are so it's a very important particle and at this point detection of the Higgs is probably the goal of particle physics the search for the Higgs actually began began at some level here in Berkeley with the discovery of the accelerator by or the cyclotron and the invention I should say of the cyclotron by EO Lawrence back in 1931 the very first accelerator that was built here was four and a half inches on the side about this big and could accelerate particles up to about eighty kilovolts not very much but pretty soon we went over to the 937 inch cyclotron which could get particles up to eight million electron volts actually many of you have seen this device because it's currently sitting up at the Hall of Science in the parking lot who seen this thing here many of you have it doesn't look like very much nowadays but it was a truly important device in the history of physics after the 37 inch cyclotron there were a number of others but before I go to some of the others let's just talk for a moment about how much eight million volts is which was what the what the 37 inch cyclotron could get us to eight million volts is about 70,000 times the voltage in 120 volt outlet to give you some sense of scale to go to perhaps a higher scale at 16 times the voltage Don the Pacific inter tie which is one of the three main inter ties that brings power from the Oregon and Washington reservoirs down to Los Angeles to be used in air conditioning down there so 8 million volts is much much bigger than you find on even the highest common system that you that's commonly available so it's really remarkable that you could get to that kind of voltages in such a small system but it wasn't enough physicists are greedy so then they went to the hundred and eighty four inch cyclotron which is built in 1942 you can still see parts of this at least you can still see the building that houses this thing as you go out of here if you look up at the Lawrence Berkeley National Lab you can see this dome at the top and the hundred and eighty four in cyclotron was built inside of that the final cyclotron or that I should say the final big accelerator built here at Berkeley was the bevatron in 1954 this was a hundred meters in diameter and could get up to about six billion electron volts unfortunately this was the end of the line here in Berkeley and the reason is that well 100 feet is really very large right and people realize that sticking large accelerators on a very steep hillside in a fire zone a few hundred meters from the major earthquake fault really wasn't such a great idea now in building these sorts of accelerators they had to change the shape the original ones were just solid disks but you couldn't build a solid disk which was a hundred meters in diameter so these accelerators became doughnut shaped and what would happen is you'd have particles that were going around and around inside of these accelerators and every time they would pass a certain place in the accelerator they get a little kick so they go around faster and faster and faster and faster well once the after it left Berkeley it went to lots of other places the biggest accelerator in the world at the moment is the Tevatron which has a ring which is 3.9 miles in circumference and can get up to just about trillion volts or something like that but very shortly perhaps later this year the accelerator called the Large Hadron Collider at CERN should come online this is in Geneva Switzerland and you can can't see it too well on this photograph but you can see there's this huge ring going all the way around it's 17 miles around to give you some idea of the scale of this device there are no roads that go straight across so if you take a bicycle you have to wander around a little bit but it takes about 30 minutes to bicycle from one side of the Ring to the other now CERN itself is a huge institution there are about 10,000 people associated with it at the moment from about 500 universities and about 80 countries if you take a look at my badge over here my badge is on 90 1666 let's not wonder about why I'm 666 but the implication of this is that there's been almost a hundred thousand people associated with this laboratory over the years now there are 20 official member countries these are the big the closest members in there unfortunately the United States is not actually a member of the CERN laboratory despite us giving them about a billion dollars in recent years this means that we don't have full privileges at the laboratory one of the privileges for instance that we do not have is we are not actually allowed to fly our flag in front of the laboratory but anyway the this laboratory has the 17-mile tunnel and inside of that tunnel there's this huge accelerator this accelerator and the detectors associated with this tell accelerator cost about ten billion dollars which is really a huge amount of money no matter how you look at it but physicists really do expect to be able to detect this Higgs particle or the god particle if you insist at the LHC because of that I mean parts of angels and demons were filmed at the LHC and at the Atlas detector here's one of these detectors which is used for figuring out what happens inside of this accelerator to give you some idea of the scale of this project when this thing is fully operational the amount of information that will be generated by this this detector will be about equivalent to the total worldwide telecommunications traffic and all of that is coming out of one little space which is a really astonishing thing well anyway the cast was at this place and you know Tom Hanks and islets zarur we're photographed and everybody was very happy to be seen with stars and things like that not me I wasn't there at the time that they filmed this but really what do all of these big accelerators have to do with using animation matter to blow up the Vatican well the answer is not very much past the bevatron the last big accelerator that was built here at the Berkeley labs do you understand antimatter as it's actually used in angels and demons we need to consider charges and particles to go way back to the beginning in fact to Benjamin Franklin who postulated that there were negative and positive Bart charges and we now know that these charges Franklin's charges are typically carried by electrons and protons electrons are negatively charged and protons are positively charged put them together in a really crude and sort of embarrassingly simple model and you have a hydrogen atom add a few more protons and electrons and some neutrons as well and you can build up our entire periodic table of normal matter the anti electron or the positron was a prediction by a famous physicist named Dirac who in 1928 had a problem with his mathematics it blew up and to solve this problem in his mathematics he invented a positive electrons it seems like a hoax but in fact it turned out to be a correct and this positive electron the positron as it's now called is simply the charge that's swapping of an electron so take an electron and change its charged from negative to positive and you'll get a positive electron or positron a slide from the change in sign positrons are believed to be otherwise identical to electrons well this wasn't just a phony thing very quickly thereafter they were discovered four years later by a guy named Carl Anderson who discovered them in cosmic rays and here's a photograph of a positron one of his originally detected positrons going through his apparatus where what are positrons from cosmic rays what are cosmic rays well the top of our atmosphere is constantly bombarded by highly energetic particles most of these particles come from outside of the solar system they come from other stars perhaps even other galaxies and they move so fast that when these particles come in and hit and say an oxygen molecule at the top of our atmosphere they split the nucleus of that oxygen molecule in fact not only do they split the nucleus they split the things that are inside the nucleus and you get a shower of different particles that come out in this depiction this proton is turning into apply several different types of ply ons and these PI ons themselves which are very strange sort of particle are themselves hit other nuclei and they split or they spontaneously split all by themselves into yet more particles and the net result is that we get a shower of particles coming down from every proton that hits the upper our upper atmosphere here's a depiction of such a shower one proton comes in and it creates initially maybe two or three other particles and each of these particles split again creating more and more particles so that we wind up with an enormous number of particles here down here at down here at ground level in fact as you sit there out in the atmosphere there are some of these cosmic rays coming down and going right through you particularly a type of particle called him called a muon and there are approximately a thousand muons per second coming down and hitting you going right through you at the moment from these cosmic ray showers now there are also naturally occurring sources of positrons there's an isotope of potassium potassium 40 which is very commonly found in things like bananas and this is a rare but not that rare isotope about one atom in every 10,000 of potassium is potassium 40 and potassium 40 emits positrons it emits antimatter's so as a result of eating this banana over the course of time that this banana and its constituents it's potassium stays in me I will experience approximately 1,000 or so positrons inside me which suddenly go out now of course if you have more bananas than you you'll get more positrons where's the lady happy well anyway um nowadays we have natural we can make artificial sources of Patras prawns in fact I have to stop eating this banana it's only about 500 of positrons will be emitted inside to me I'm one of the most potent artificial sources of positrons that we can make and by the way we make these by transmutation of elements inside of other accelerators but one of the most potent ones is an isotope called sodium 22 and I was actually able to borrow a sample of sodium 22 and it's inside here inside this bubble chamber emitting positrons which unfortunately I'm not really seeing at the moment but what we were going to show you is some tracks of positrons coming out of this device this is all set up right well it's about as working as well it's supposed to I see all sorts of other things coming in here actually you guys can take a look at what's coming in here perhaps if we could have the camera on the auxiliary video is this working you can see in this camera over here oh it's chemistry yeah okay most of what you see there are not particles but every now and then you should be able to see a streak that goes through this image and those streaks are mostly cosmic rays but our sodium source of positrons is this thing over here and if you look really closely at least before the lecture when this was working an hour ago you could see that there were positrons being emitted by that source and you could see the tracks left behind from those positrons as they go through but unfortunately I'm just not seeing them at the moment if you want to come up after the lecture this may be working by that point sometimes it takes a while for this to get going I apologize for that but we're just going to have to move on okay the artificial generation of positrons has become quite important lately in the medical profession because we can use positron emission tomography to learn a great deal about what goes on inside people especially sick people what happens is that you are forced by your doctor to drink or breathe or you have injected into you some radioactive isotope that emits positrons and those that radioactive isotope is absorbed in various organs inside of your body depending on whether or not that particular isotope has some particular metabolic activity for the particular isotope that you're I'm not saying this very clearly if for instance you ingested something like iodine it would go straight to your thyroid right and if it was radioactive you could see your thyroid lit up like this well in this case you can't see this very well but there's a person over here who was forced I think to have some radioactive substance that emits positrons injected into his veins and you can see that they all concentrated inside of this person's stomach something's actually wrong with this person and it's a very it proved this proves to be a very powerful diagnostic technique for doctors well that's positrons what about antiprotons just like there are antielectrons there are anti protons if you take a proton which is positively charged and swap its charge so that it's negative rather than positive you'll get an antiproton and just like with electrons and positrons aside from the change in fine anti protons are thought to be otherwise identical to positrons and I'm sorry two protons so it turns out that the very first anti protons were discovered here in Berkeley at the bevatron that accelerator that I showed you a few minutes ago they're made in a process which is quite analogous to the way positrons are made in cosmic rays you take a beam of protons and slam them into a metal and after after this collision some a very small number of anti protons will come off of that metal the first ones were made as I said in Berkeley in 1955 by sue gray and Chamberlin sue grey is the short one Chamberlin is the tall one in this picture and they received the Nobel Prize for this work now just like today publishing is very important but unlike that today they didn't have the World Wide Web to publish their results so there's a really neat photograph of how they published their results at least within the local of Berkeley community it's a photograph of a blackboard which shows that on October 6 at 4:30 p.m. they had detected 38 negative particles of the appropriate mass in other words 38 anti protons just at this moment know if matter then is just made of negative electrons and positive protons negative electrons and positive protons an antimatter is made of positive electrons and negative protons positrons and anti protons over here and they're just basically swapping the charge why would we care about all of this what's so different about antimatter compared to matter well the answer is that if you allow matter to touch antimatter it blows up it annihilates and when it annihilates all of the matter all of the mass turns into energy via Einstein's famous equation e is equal to MC squared you get an enormous amount of energy out of this process in the Angels & Demons book about a quarter of a gram of antimatter is stolen from CERN this is equivalent to 10 grains of rice and yet if you took 10 grains of antimatter rice and allowed it to touch normal matter it would cause an explosion that would be the ten kiloton of TNT explosion for comparison the bomb that blew dot was blown up over Hiroshima was 15 kilotons now that 15 kiloton weapon contains 64 kilograms of uranium inside of it so the fact of the matter is that you get an equivalent sized explosion out of these grains of rice even though they weigh about 250,000 times less as was used to blow up Hiroshi MIT said truly an enormous explosion and this would deal enormous damage to the Vatican if it was used if we start at the Gaza send petrol and go outwards just to get some idea of what vatican city looks like and then if underneath the obelisk in the middle of the plaza I was to allow those 10 grains of rice to blow up I would get a circle of devastation about this big in other words everything within this range would be gone and there would be very very significant damage well beyond that point so you really could in principle do a lot of damage to the Vatican if you were to blow up some antimatter there but we actually shouldn't fear for the Vatican and the reason is that the economics associated with antimatter production are utterly and completely infeasible why is this well antiprotons are still made the same way they were made back in the bevatron here in Berkeley by crashing very energetic protons into a metal and only a very small fraction of the protons turn into anti protons about one in a million this fraction results from fundamental physics not technology and is not likely to change all that much to make a one gram of antimatter would require the entire world to energy production for about a hundred years now what do I mean by that everybody would have to stop cooking driving their cars lighting their houses using the Internet absolutely all of the uses of energy in our society would be have to be funneled over to CERN or some equivalent accelerator for a whole hundred years for a century to make a mere one gram of antimatter and that's looking at it on the bright side in actual fact accelerators like the bevatron have what is called a wall plug efficiency they don't manage to take all of the electricity that you put into them and put them into the particles at best they're about 10% efficiency so our hundred years has now become a thousand years and things get worse than that if you take a large number of antiprotons and put them into a small space they don't like it you can exact exactly the same effect by trying to put a large number of electrons into a small space and in a moment if this actually starts to work I'm offered one for my demo so far today all right I'm going to cheat in a moment this is pathetic what happens as you've all seen in the sim this is a Van de Graaff generator I'm sure you've all seen this before what happens if you put too many of them into a small space is they like to spark they're going to repel each other they don't like to be all gathered together and in fact all of these antiprotons are going to vanish our ability to trap antiprotons into one small space is rather limited and when you include that factor in our thousand years becomes about a million years so unfortunately or fortunately depending on your point of view we're never going to be able to generate the one gram of antimatter that would be equivalent to make a substantial weapon in many ways this is a real shame because we could get to the stars on about this much antimatter this much antimatter would take a hundred kilograms space probe and accelerate it to about the tenth the speed of light which would be more than sufficient for sending a probe to the nearest stars if you wanted to go to a near star yourself you'd probably meet it need a spaceship that would say on the size of 747 and we could get that to go to a tenth of the speed of light with about a thousand kilograms of antimatter so it's a real shame really for at least space exploration that antimatter fuel isn't a practical thing but the facts of economics dictate that it is so why should we study antimatter if aside from the science wops and this mat minor fact that it blows up antimatter is thought to be identical to matter why bother doing this at all well there are many reasons to study antimatter one of them is that we don't know how antimatter interacts with gravity it's certainly well known that apples are attracted towards earths and everybody believes that anti apples would be detracted towards anti Earth's but it's an open question about what would happen to an anti apple would it fall down towards Earth some physicists have speculated that in fact an anti Apple would fall up and will go away from Earth the betting is against it but it's a possibility it's something that people want to think about and we have absolutely no experimental evidence on this question there's an experiment at CERN that's trying to look into this question it's not my experiments it's another one and the way they propose to do it is to fire very slow anti protons anti protons that are moving at about 100 meters per second which is about the slowest that we can get them down a one millimeter to the protons will be deflected downwards by Earth's gravity they're going to fall presumably the protons are the anti protons and they would fall by a distance of about half a millimeter this is a large distance as physics experiments go it would be easy enough for us to detect that they had fall fall in such a large distance so this sounds like a great experiment but there's a catch because inside of this tube there are electrons in the walls of the tube they're always going to be electrons and if for some reason one of those electrons went from the top tube down to the bottom tube that would create an electric field which was pointing vertically and this electric field would be due to the charge imbalance between these two plates unfortunately that electric field would also push on our anti protons and it turns out that it would deflect them by a distance that is more than the distance of gravity in down this one millimeter tube instead of falling by half a millimeter they would actually the way I set it up go up by almost 10 millimeters which would completely swamp out the effect that we were trying to measure because it's absolutely impossible to have the two sides of these tubes be so well balanced that there's that there isn't even a one electron difference between the top and the bottom of the two so what could you do about this well the reason the antiproton is deflected by the electric field is because it's charged neutral antimatter would not be deflected by the electric field and could be used to measure the effects of gravity on antimatter what do I mean by neutral antimatter well just like we can make a hydrogen atom by taking a proton and having an electron go around it we can also make anti hydrogen atoms by taking an antiproton in the center and having a positron go around the outside this net object as a whole is electrically neutral and won't be affected by the electric fields that we could have gotten in our trap so we can use anti hydrogen atoms to measure gravity there are yet more reasons to study anti hydrogen atoms one of the things that we would like to do with them is to look at the spectrum of anti hydrogen if you take a look at any gas and you run an electrical current through it or some other way of running well basically run an electrical current through it it's going to glow here's for instance mercury glass glowing and over here is neon glass gas glowing and you can see that they glow with different colors well we would like to measure the colours at which hydrogen and anti hydrogen glow and determine whether or not these colors are identical you know what does this essentially mean measuring the colors of that these things would glow at is in some loose sense equivalent to measuring how much time it takes of an electron to circle around the hydrogen of the proton in the hydrogen atom and measuring how much time or with what frequency positrons circulates around the antiproton in an anti hydrogen atom the the rate or the frequency that they rotate around that is going to do term in the color and it could so happen that they rotate at different frequencies in other words it could happen that this positron goes around just a little bit faster then the electron goes around if that was the case the color emitted by these atoms would change the anti hydrogen would become more blue well actually these both emit in the ultraviolet and it would become more ultraviolet Li but I can't but ultraviolet up on the screen so we'll just have to accept this analogy over here now is this likely to happen well no according to one of the grand theories of physics there's something called CPT symmetry which I'll get into in a minute and see if you treat symmetry is really one of the deepest things that we know and according to CPT symmetry the spectra of hydrogen and on hydrogen have to be the same they could only be different if CPT symmetry is unbroken is broken now this is very very unlikely it really is but it is worth studying because proof that CPT could be broken would really revolutionize physics it would surely be rewarded by a Nobel Prize so what then is CPT well I'm sorry why why should we use anti hydrogen for look to look for CPT violations well it turns out that one of the things that we can do most accurately is to compare the rate at which these electrons circle that proton and this positron circles the antiproton it turns out that we can compare these so accurately that we could detect a difference of one part in one followed by 18 zeroes that's really an astonishing fact in reality these electrons go around crudely speaking about a quadrillion times per second imagine that a quadrillion it's a number that it's hard to even imagine how large that number is if it was if one this positron was to go around just a little bit faster so that after a thousand seconds it had gotten ahead by one full revolution remember it's going around a quadrillion times per second and I'm saying if we could if this thing got ahead by one revolution in a thousand seconds that's something that in principle we could measure so this is an incredibly sensitive test of whether or not they're going around at the same speed now what exactly is the CP T symmetry that says that this can't possibly happen well each letter in CP T stands for something that can be flipped C stands for charge conjugation P stands for something called parity conjugation and T stands for time reversal now consider the results of an experiment in which one of these things is flipped let's say I have an experiment over here and I conduct an identical almost experiment over here except I take everything say the charge in one of these experiments and flip the charge so over here I had only minus charges over here I had positive charges under some circumstances the results of that experiment will be identical and let me go into this in just a little bit more detail for instance let's take the C charge conjugation that says that the signs of all the charges are inverted positive charges become negative negative charges become positive now let me do an experiment let's say I have two positive particles two protons and I have my fingers on these two protons and then I suddenly let them go what are they going to do everybody knows this they're going to repel each other they're going to go flying apart right now let's say instead I took these two positive particles and flipped their signs so that they both became negative particles I have my fingers on them and then I let them go what's going to happen exactly the same thing in other words flipping the sign of the charge at least in this experiment results in the same net result what about time reversal well I've got a really neat demonstration that most you time-reversal over here you've probably all seen versions of this this is just two balls which are free to bounce back and forth this one's particularly amusing because the balls are different this ball weighs three times the amount of this ball weighs yeah what I'd like to do is to let this light ball go keeping the heavy ball stationary and I want you guys to watch the pattern all right if you're a physicist this is absolutely amazing because what happens after every other collision the heavy ball is stationary we start that up again so here we go I'm letting this one go stationary stationary stationary stationary that's really kind of neat at least if you're a physicist this is an example of a collision collisions are really important in physics there are all sorts of ways collisions come up and and in physics and this is one of the important this is one particular case and it's possible for us to understand how this actually happens we can apply the standard equations of conservation of momentum and conservation of energy and we can solve for this system and we'll get the right answer and it will predict indeed that one of those balls will be stationary after every collision but there's a much better way to do this and the better wave proceeds by taking a movie of that and I've got a movie over here and you can see this movie it slowed down a little bit you can see that time isn't dancing on that clock over there okay a movie of what you just saw in real time now let's say I take that same movie and run it backwards in time on the top is the original movie you can see this clock is counting up in time and on the bottom I just time reversed this thing the clock is counting backwards the movie is running backwards and what I want you to see is that when you do this it looks exactly the same everybody see that the time reversed version of this experiment is exactly the same as the original version and this is an example of t symmetry time reversal in physics I take an experiment and somehow or other I get time to run backwards and I get exactly the same result the last letter in CPT symmetry is something called parity parity is a little bit more complicated could I have the lights back on here please but parity is best explained by gloves to bicycling gloves in this particular example one of them is a right-handed glove the other one is left-handed glove now let's think about these two gloves for a minute is there any way that I can twist and turn this left-handed glove and turn it into a right-handed glove all right there's no way by simply moving it around and twisting it and turning it that I can turn my right-handed glove into a left-handed glove but as somebody in the audience did say to take a more worn out glove of mine if you take a right-handed glove and you turned it inside out it becomes a left-handed glove something that I've used on occasion when I've taken two right-handed gloves - a bike ride so this is an example of a parity transformation actually a better way of considering parity a more physics way of considering a parity transformation is to imagine looking at these two gloves and then just looking at one of them but looking at it through a mirror what's going to happen if I take a look at this glove through a mirror well it's the same thing that always happens when you look at something through a mirror your right hand turns into your left hand this left handed glove is going to turn into a right handed glove if I look at it in a mirror and that's the parity transformation if I take an experiment and turn everything that's right-handed into everything that's left-handed we what it would mean by something that's right-handed in something that's left-handed well there are gloves but maybe something that's got a little more physical it's a little more familiar to you as sugar molecules those of you who are chemists or study chemistry or biology know that there are right-handed sugar molecules and left handed circular molecules right so the experiment consists of taking an experiment over here and taking everything that's right-handed and making it left-handed and taking everything that was left-handed over here and making it right-handed and running that experiment and when you run that experiment the results at least under certain circumstances will be identical it doesn't matter that you did this parody transformation actually parity transformations are discussed in the movie itself they don't actually use this world but there's a big discussion of it because in the movie a big thing is made out of the logo for the Illuminati and this logo for the Illuminati is what's called an ambigram that's that's a real term not invented by the book or the movie the thing that's special about an ambigram is that if you rotate it by 180 degrees it turns back into itself now in the book and presumably in the movie there's the big mystical moments about this sort of thing it's actually rather run Dame from a physicists point of view we would call this a parody conserving rotational symmetry and the representation than the so3 rotation group but never mind it's rather boring a more interesting parity transformation would be a mirror reflection here I've taken the Illuminati logo and nerve reflected it I've just looking at it as if it was through a mirror and you can see that there's no way for me to rotate this and get that okay this is a fundamentally different object than these guys over here this would be a mirror image the transformation that takes this one over to this one is something that violates parody actually you can have mirror images that don't violate parity this is for the movie buffs out there here is a logo that appeared in a movie some years ago back in 1985 actually and it's a mirror ambigram you can see that if I was to reflect this through a mirror I would get exactly the same thing anybody know what merit that what movie this comes from back to the future this is a DeLorean Motor Corporation logo anyway let's get back to CP T so what is it about CP T as I said each letter stands for something that can be flipped charge parity and time and if we take some experiment and we turn all at the flip all of the signs minus becomes plus we flip all the parody left-handed becomes right-handed and we turn time from going forwards to being playing backwards then the experiment that we do will be identical now physicists really believe that this is true that if you flip all of these three things and you have to as it turns out put all of these three things if you just flip one of them or if you flip some combination of two of them you won't get exact - the same thing happening but the CPT theorem says that if you flip all of these things you will wind up back with exactly the same thing happening on the other hand yes know the cpt that's above my paygrade entropy and time reversal and all of that are very complicated questions I'd be happy to discuss it with you afterwards but those are really really hard deep philosophical questions within physics but it does apply to big systems as well as small systems okay um why should we really bother if everybody believes in the cpt theorem it doesn't seem like there'd be much point to investigating this question of whether anti hydrogen breaks the cpt theorem but the fact of the matter is there are outstanding problems there which do not seem to agree with the results as the cpt theorem we exist because there's almost no antimatter in our universe if there was a lot of antimatter in our universe we would be blowing up on a regular basis when we look out into the Stars we don't see any antimatter out there and we can detect antimatter we could detect antimatter if it was out there we could detect it without too much problem but it wasn't always that way back in the beginning right after the Big Bang the Big Bang fourteen billion years ago should have produced equal amounts of matter and antimatter and if I take some large amount of matter and combine it with some large amount of antimatter the net result is it should all be gone everything should have annihilated and yet we know unless this all is a figment of my imagination that something was left behind us so of all of these particles out there there must have been some sort of imbalance that resulted in us being left behind now how could that have actually happened well there's all sorts of ways and speculate about it but it seems likely that it didn't start out exactly balanced there must have been just a little bit more matter than antimatter in the beginning after the Big Bang and nobody actually knows how to explain this this is an open hole an embarrassing thing in physics we can't explain this and maybe this is because CPT which sort of guarantees it CPT and other theorems guarantee that they should be exactly balanced maybe they weren't exactly balanced so it is worthwhile looking at these deeper questions even if we expect that CPT probably is is an OK theorem is a correct theorem so CPT and gravity story studies both require anti hydrogens CPT probably requires trapped anti hydrogen certainly precision gravity studies require trapped anti hydrogen as well have we actually made any anti hydrogen the answer to that question is yes the first anti hydrogen atoms ever made possibly the first anti hydrogen ever atoms ever made in the history of the universe were made at lire in 1996 Lear was an accelerator and they made about nine of them which isn't really that impressive 99 more were made at the Fermilab but these antimatter atoms were made in a fashion that caused them to be traveling at about 90% to the speed of light after they were made and it's fairly hopeless trying to study something that's going at 90% of the speed of light because it leaves your apparatus almost the instant it's created in the first place so what physicists would really like to do is to create slow or trapped anti hydrogen and that's been done by this point at first by the Athena collaboration at third CERN in 2002 and very very shortly thereafter by the a trap collaboration altogether we've made on the order of a hundred million anti protons now 100 million sounds like a lot but it's really not if they were tightly packed they would form a box that was about a hundred nanometers on the side that's a box which is so small that we couldn't actually see that box the whole net result would be that they would weigh a hundred millionth of a gram and if I was to use this as an energy source it would be sufficient to run this laser pointer for about one second so really we haven't made been able to make very much antimatter at all in fact we've made so little of it that it's very hard to detect that we've made it in the first place this is an image of one of the first anti hydrogen atom slow anti hydrogen atoms that was made and detected what it is is an annihilation event there was an anti hydrogen atom over here which hit the wall of a trap which generated two gamma rays going off in opposite directions and some particles which are called prions which go off in four more directions these things were detected by particle detectors which are these lit up boxes over here altogether the sort of apparatus that it takes to detect that anti hydrogen one's made the sort of detector that is necessary to detect that anti hydrogen is made costs on the order of a million dollars so you can see that if it costs us a million dollars to make a detector that can detect anti hydrogen there's really no chance that we'll be blowing up the Vatican anytime soon how do we actually do this well we have to make an antimatter trap and here's the antimatter trap from Angels & Demons here's a photograph of it I don't know what and our antimatter trap is going to look like in the end I mean we have some prototype traps now but I'm absolutely certain it's not going to look like that for one thing we have to worry about how we would keep stuff inside of this trap and we have to be able to make a bottle of antimatter in which the antimatter actually stays around so what are the issues associated with getting it to stay around well if the was any air inside of that trap the antimatter would annihilate on the air because eventually the antimatter would find particles of matter in the air and they would blow up and that would be the end of it so we have to be able to make a trap that has absolutely no air in it well fine you say some of you have worked in similar fields you just take a big pump and you pump all of the air out that turns out to be not even close to good enough you have to do a lot better than using normal vacuum pumps to get out of the air one of the things that you have to do is to cool the trap down inside here I've got some liquid nitrogen this is at 77 degrees Kelvin it's very cold I'm going to fill up this this little thing with liquid nitrogen you can see it's boiling at this moment and but it will eventually stop boiling see if I can fill up the rest and now I've got a nice little gobble-gobble of of liquid nitrogen it's really cold just to show you how cold it is do a little demonstration I've got a rose here we're going to freeze this rose I'm going to let it sit in there for a little bit anyway we're going to have to take our trap our bottle and cool it down to temperatures which are even colder than the temperatures of liquid nitrogen we have to get their trap down to temperatures of liquid helium because it turns out that when we really cool down our trap all of the gas inside of that trap just condenses on the walls of the trap and that's the only way that we can get a vacuum which is sufficiently cold as sufficiently good so that the matter doesn't vinaya late I think this is pretty cold by now let's see what happens with it rose petals it just it got to be so cold that it just shattered when I slammed it against the table okay so we have to make our trap little really really cold and let me tell you this trap of angels and demons doesn't look cold to me that looks at room temperature so it's not realistic in that way but there's another problem let's say we can get all of the air out we still have to keep all of the antimatter from touching the sides of our bottle because after all if it touches the sides of our bottle it's going to annihilate so we have to build the bottle which doesn't actually have any physical sides how do you build a battle bottle out of nothing the way you build a bottle out of nothing is to use electric and magnetic fields and here's a picture of our trap basically what we have is we have a series of electrodes and we put our antiprotons p-bars an abbreviation for that in an over here and our positrons in over here and we set up an electrostatic well which is just basically a valley made with electric fields and that traps the particles in in the axial direction it's a little bit harder to get them trapped in the radial direction but I can show you how we do it with this demonstration over here assuming this demonstration works which oh yes it is working if you could zoom in on this at the moment on this camera I'm sure you guys can't see this in the back Oh what do I have to do here I have to put this on in jewelry right okay yeah what you can see here I hope is right over here as you can see a beam of electrons which is being emitted by an electron gun and as you can see that beam of electrons likes to travel in a straight line and so it very quickly hits the glass the sides of the glass over here and basically electrons will get absorbed by the glass in other words these electrons are not trapped however I can use these coils over here to turn on a magnetic field and the net result of turning on those magnetic fields is that that electron beam will be bent I'm going to turn the electron beam on slowly and you can see that I'm starting to bend that electron beam into a circle and eventually I can get the beam to bend back onto itself well this is how we can store charged particles in a trap without having them touch the sides basically we apply a strong magnetic field the particles all want to go out but the magnetic field bends them around in a circle and they come back to where they started let's go back to my presentation how do we make anti hydrogen well once we've got the particles in the trap like this we somehow have to mix those particles together and we can do that basically by electrostatically tilting the trap and when it tilts they just run into each other and when they collide and overlap like that they're going to make some anti hydrogen at this point I could go into one of my normal normal seminar modes and start doing a lot of technology with you and a lot of physics with you but I think it's inappropriate for the audience so at this point I think I'm going to leave how we actually do this because it really does get quite technical very quickly and just cover in the very few remaining moments a few other issues from the book so Oh actually I'm a little bit early anti hydrogen creation has been very successful our next step is to actually trap the anti hydrogen atoms that we have not succeed in doing so we can make anti hydrogen but we can't yet get them to stay within the bottle and that's really the next step here and with that no not quite with that we're going to use for those of you her expert sweer going to use a magnetic the anti hundreds in the magnetic moment to trap it in a minimum v field and with that i'd like to talk about some other issues within the book according to the book CERN owns an x 33 space plane I don't know about this I know that they have certainly not sent it to San Francisco to pick me up they are however willing to send the shuttle to the airport to pick me up in the book CERN is a beautiful campus and there is a beautiful building at CERN this really is a very very nice building actually not only is this a very pretty building it's a great architectural pun because it's built to look like a cyclotron everybody see that this outer thing here is this big magnetic coil and the center cylinder in the center is this part of the building out there so it's a great architectural pun unfortunately it is not representative of the way the rest of CERN looks certain actually is rather rundown industrial here for instance is my beautiful office in a trailer do they have indoor skydiving at CERN there's a scene in the book in which they have indoor skydiving much to my surprise I talked to a friend of mine today who does parachute jumping indoor guy driving his wheel there's a facility not far from here where you can go indoor skydiving and I have a movie come on I have a movie showing you indoor skydiving just for fun it's about 10 seconds anyway the way that works if I could have the lights back on is this a giant fan which blows people up and you really can float on that if you know what you're doing it costs something like a few hundred dollars for a half-hour session so it's not a cheap hobby but you could do it and a big point of made of this in the book that the facility to do this exists at CERN how many think people think that there actually is a facility to do this at CERN wait these are my graduate students they spent a lot of time at CERN but obviously they've seen a part of CERN that sadly I have not anyway I'd like to conclude by thanking a whole bunch of people in particular Roberto over here really helped me a lot with a lot of these demonstrations but lots of other people have helped with me meet with this too and I'm going to conclude by reading you a poem that was published in The New Yorker back in 1956 commemorating the discovery of the antiproton well up beyond the troppo strata there is a region star constellar we're on a streak of antimatter lived dr. Edward anti teller remote from fusions origin he lived on guests and unawares with all his anti kathan kin and kept Makassar on his chairs one morning idling by the sea he spied a tin of monstrous birth that wore three letters AEC out stepped a visitor from Earth then shouting gladly over the sounds met two who in their alien ways were like as lentils their right hands and the rest was gamma-rays all right it doesn't scan very well but never mind that thank you very much for coming I hope you've learned something about antimatter [Applause]

Channel: UC Berkeley Events

Views: 210,563

Rating: 4.5030837 out of 5

Keywords: uc, berkeley, ucberkeley, event, physics, science, antihydrogen, Joel, Fajans, CERN

Id: _sqYh8puZ-I

Length: 65min 8sec (3908 seconds)

Published: Tue May 19 2009

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[u/alllie]

Why physicists would love to trap antihydrogen, but the Vatican need not fear..." is about the science behind Dan Brown's novel and the new movie "Angels & Demons" that premieres May 15, 2009. Professor Joel Fajans will give the lecture, suitable for all levels of understanding.