 Hello, my name is Dr. Looney, that is my real name. Yes, I have been told I should go into psychiatry. Simple physics is all you need to explain the vibrations of what is really just a piece of wood, but which can still produce these beautiful frequencies which affect our minds. So my job in the patent office involves assessing new inventions. And again I'm using that simple physics which explains simple systems and applying that understanding to more complex systems in order to understand these new inventions. I was always quite musical. In my teenage years I started teaching myself guitar, basically because I was a bit shy of girls I think, I just used to stay in my room and play with my instrument. So that's where the music came from. As I got into my A-levels and my degree started doing physics, I realised that music is physics basically. Through my research at Cardiff University what we were trying to do was link the vibrations of the instrument to the sounds we hear. Now when I play a guitar here you can't see the vibrations. All you can do is hear the sounds that those vibrations produce. So in my research we used holography, lasers to illuminate the guitar and in that way you can actually see the patterns of vibration of the guitar which allow us to understand how those sounds are produced, which frequencies come from those modes of vibration of the guitar body in order to produce the sounds we hear. I think I just never grew out of science. There wasn't a specific event I don't think that made me a scientist. I think kids are naturally scientists and then they just go and do stupid stuff. People start off as scientists because they're curious. Kids are just curious about everything, about their environment, about their universe. The moment you stop being curious is the moment you stop being a scientist and that happens all too quickly for a lot of people. I've got the best job in the world. I get to play rock guitar and get paid for it and talk about physics which I love. So I think I couldn't possibly do a better hour's work than that really. Lord Winston. Sorry that's the wrong lecture, that's the advanced class next week. Hello my name is Dr. Looney, that is my real name. Yes I have been told I should go into psychiatry. Are you mentally ill? Go and see Dr. Looney. And yes I've also been told there will look like a weird cross between ant and deck. So let's get that sorted out. And I'm going to talk... I'm going to tell you about sound and vibration. How come when I hear a... I just can't get no... What is it about this stuff, this equipment that causes that revolutionary history change in sound? So I'm going to talk about sound and vibration for a bit. Then later on I'm going to try and melt your brain. It's going to get a bit weird. So firstly, vibrations. Vibrations are all around us. What I'm doing with this air bazooka is I'm sending a pulse which travels through the air until it hits something. I need someone with kind of long flowy floppy hair. This lady right here if you'd just like to stand up just for a moment. I'll just try and move it. Don't hold your hair. I've got to try and move it for you. Have you conditioned today? Alright, round of applause for our volunteer there. See what I'm doing there is I'm kind of sending a pulse of sound but with two big differences. Firstly that was far too powerful to be a sound. We don't detect sounds with our hairstyles. She might, I don't know. We just detect sounds with tiny little bones and hairs in our ears. Secondly that was just a single vibration which stopped. Sound is usually a continuous vibration and the number of vibrations in a second is called the frequency. In fact all I'm doing right now is I'm shaking the air around at different rates, different frequencies in order to do something called talking. Here at the bottom of my neck there's a little fleshy flap. When you blow air over something like that it makes a sound and the frequency of the sound depends on the size of the flap. So a tiny little plastic flap like this you blow over it and you get a really high pitched monkey noise. That's why babies have got such a cute little high voice because the flap is very small. Then as you grow older the flap gets bigger and your voice gets deeper. That's why teenage boys sound a bit weird. I'm going to have a cup of tea! It's because the flap is growing faster than they can learn how to control. That's also why they're a bit clumsy as well. Their limbs are growing faster than they can learn how to control. That also applies to other parts of the body as well. Above the little flap I've got a tube of air in my neck. Obviously the tube isn't that long. If it was that long I'd be talking crap. But a tube of air has its own resonances and they're the frequency from the little flap that gets emphasised or accentuated. I can change those frequencies by filling the tube in my neck with a gas other than air. As I'll seek to do right now. Hey soft lad, don't be all ass. Now it might sound like the pitch of my voice has been raised. It hasn't actually. If I were to sing along with everyone else, I'd sing in tune. Just a minute. See the trouble with helium is it's not oxygen. So I've filled the tube in my neck with a gas other than air. That's changed the resonances of the tube and made my voice sound different. Your teachers might have told you that helium tightens your vocal cords. It doesn't affect the little flap at all. It just affects the resonances of the stuff above it. And then finally from the top of the tube, this equipment here, my teeth and tongue and lips, shapes or filters the sound from the top of the tube. Bit like a war war pedal. In order to do something called talking. And maybe it's because we humans have got such an incredibly good control over this apparatus that we could create the entire symphony of sounds and therefore language and therefore civilization. Whereas chimps and maybe even Neanderthal man or lake would manage was the odd oasis song. So I'm shaking the air around at different rates. If you try and shake the air around too fast, yeah, behave. If you try and shake the air around too fast, what happens is the air can't get out the way of itself in time and you get a shockwave or sonic boom. I'm going to try and create one now. So let's try another one. Ah, there's a good one. One more, try and get a really good crack. So what I'm doing here is I'm sending a kink, yes, a kink, along the whip. I actually bought this in a really dodgy shop in Wales, right? Guy said, what, you want this for a physics show? What kind of pervert are you? So I'm sending a kink along the whip. The fact that the whip gets thinner and thinner, it tapers along its length, that means that the kink travels faster and faster until at this tiny little stringy bit at the end, it's going 700 miles an hour, the speed of sound. Again, the air can't get out the way of itself in time and you get a shockwave. So I'm shaking the air around, but air isn't the only thing that can carry a vibration. Other media can vibrate as well. Water can carry a sound. The mating song of the blue whale can travel hundreds of miles under water. In fact, before ship engines came along, two whales might have been able to hear each other almost anywhere in the world. It's so much louder than a jet engine when it's like comparing a jet engine to someone shouting. Imagine living next to one. Hello ladies, come and get it. Maybe that's why they're endangered. Where's the whale? So air can vibrate, water can vibrate, solids can vibrate as well. An earthquake could literally be said to be the sound of heavy rock. The vibrations of a bridge or a building could be said to be the sound of heavy metal. And I'm going to show you how all these different vibrations follow the same simple maths, maths of sine waves. And if you understand that, you can understand almost anything, possibly everything. So let's get back to the sound of rock guitar. To understand the sound of rock guitar, first you've got to look at the string. I'd like you to think of a string as a kind of stretched out spring. Now the frequency of the simple side to side vibrations of a string or a stretched spring, what's called the fundamental frequency, depends on three things. Firstly, the length, the shorter, the higher. When I put my finger on a fret, I effectively shorten the length of the string so the frequency rises. Secondly, tension, the looser, the lower. When I press down my whammy bar, I decrease the tension in the string so the frequency drops. And finally, thickness. All of these strings are the same length and the same tension. It's just the lower pitched ones are thicker. And to get really low notes, they've got to be really thick, which curiously also applies to bassists. So here we've got an animation of the string in its fundamental pattern of vibration. We call it its fundamental mode. That's going about once a second or one hertz. A guitar string might be going a hundred times a second or a hundred hertz, but still with that same pattern of vibration. But there can't be just a hundred hertz coming off this string. If there were, then when I turn this knob, which cuts out higher frequencies, it would have no effect. But you can hear that... You can hear that higher frequencies are being cut out. So where do they come from? They come from the harmonics of the string. Now, 3,000 years ago, Pythagoras supposedly discovered the harmonics of the string along with that triangle theorem we all learn in school. You've all done that yet. The Pythagoras right-angle... He actually discovered neither of these things. He was just a legendary figure with a golden thigh who told people not to eat beans. And the only reason the triangle theorem was named after him was because he killed a cow when he heard about it off someone else. I wish it was that easy to get your name in history. E equals MC squared. Oh, really? That's my theorem now. Thanks very much. But let's pretend he discovered these, the harmonics of the string. Over on the left is the fundamental. I've slowed it down even further. But at the same time, a string vibrates in another pattern, having two regions of vibration twice as fast as the fundamental. That's twice the fundamental frequency. That's called the first harmonic. And at the same time as well, it vibrates in another pattern, having three regions of vibration at three times the fundamental frequency. And four times. And five times, six times, seven times, if we were to carry on. So if this fundamental was going at 100 Hz, 100 times a second, I know it's not. Just pretend it's faster. Then it's these harmonics at 200 Hz, 300 Hz, 400 Hz, all the way up to human here in range of 20,000 Hz, that provides the higher frequency content of the string. So if I rest my finger halfway along the string, so that it vibrates either side of my finger, twice the fundamental frequency, I hear the first harmonic. First harmonic. Fundamental. First harmonic. Fundamental. Hear the difference there? If I rest my finger closer to the end of the string, a third of the way along, I hear the harmonic of the second kind. Closer again, I encounter the third kind. And the fourth, the fifth, sixth. When I pluck a string, I excite all of these different patterns of vibration at once, but because there's a nice mathematical relationship between their frequencies, 100, 200, 300, so on, that's why strings sound nice. Trouble with strings is that they're very quiet on their own. If I turn my volume down and just play the strings alone, you can hardly hear anything. Somehow the string's got to get its frequencies to our ears. Now, in a classical or an acoustic guitar, what happens is the string vibrates a thin wooden plate. That plate can move more air around and get the string's frequencies to our ears more effectively. And you can actually see the vibrations of an acoustic guitar if you take a hologram of the instrument. And you can tell me what a hologram is. What's a hologram? Who's never seen a hologram? You've all seen a hologram. How would you describe what you saw? What's the first thing that would come into your head if it said hologram? A distorted image. That's getting there, isn't it? That can be a distorted image as well, can't it? It's a projection. Well, these are projections as well, but they're not necessarily holograms, are they? What's the difference between a hologram and a photograph? Sorry, what's your...? 3D. It's a 3D image. Well done. Round of applause for the person up there. Yeah, a hologram is a three-dimensional image. A photograph is just flat, two-dimensional. So remember this for later. A hologram takes three dimensions worth of information and stores it on a two-dimensional flat surface. Remember that for later. So if you take a hologram of a guitar, you can actually see the vibrations at different frequencies, the different patterns of vibration of the plate. I did some PhD research on this, and if we understood how all of these different patterns of vibration fitted together in physics, we say how they're coupled, we'd have much more control over how to build guitars. So that's classical in acoustic guitars, but let's get back to the electric guitar. In an electric guitar, we don't want the string to vibrate a thin wooden plate. This is a solid block of wood. We don't want it to vibrate at all. Instead, what happens is that the string vibrations induce sine-wavy electrical signals in the wires wrapped around these magnets. They're called pickups. They pick up the string's vibration. So for each of those harmonics, those different patterns of vibration, there's a sine-wavy electrical signal of a certain frequency coming out the lead of the guitar. The trouble with those signals is that they're very weak. What has to happen is that they're sent to an amplifier. The amplifier takes alternating current from the mains, turns it into direct current, AC-DC, and uses that current to boost these incredibly weak signals. And the trouble with that is that they're very fragile. It's very difficult to boost the depth of the signal, the volume of the signal, and still keep that nice sine-wavy shape. Guitarists in the 1960s started turning the volume up past the fidelity limits of the amplifier, which started squashing the top of the sine waves, distorting their shape. And you know what? The squashed waves sounded cool. That squash top gave each harmonic harmonics of its own. Those false electronic harmonics started getting their own false electronic harmonics until eventually plucking the string caused a huge rich cascade of new frequencies. That cascade of harmonics turned the simplest riff into something powerful. You could get great results without necessarily requiring great expertise. Yeah, thanks very much. Add to the fact that it's so economically cheap just to put some wood and magnets together, so even working class kids can afford it. You've got the sound of a revolution. So we've seen how just understanding a bit of simple maths, simple maths of sine waves, you can get a very deep understanding of something you might have thought was so complex as to be almost magical, like the vibrations of a musical instrument. That's what physics is about, really. You start simple, and you work your way up to more interesting, more complex system. Yes, the stuff we do at school can be a bit dull. You know, mass on a spring. Woo, that's exciting. You know, biology, you get to cut stuff up. Wow, chemistry, you get to blow stuff up. Wow, physics, mass on a spring. We've got to walk before we run, right? But if you think of each of the atoms in our bodies as a little mass and the forces between those atoms like little springs, then you say, ah, I'm starting to get the bigger picture here. So what else? What else might the physics of guitar strings possibly have any relevance to? What about everything? Everything? Everything. String theory! The theory that all the particles in the universe are like the different harmonics of the same tiny strings. String so tiny that comparing them to the size of an atom is like comparing a guitar string to the entire universe. Or a copy of pilot crap, I don't know. Only a few thousand people in the world really understand string theory properly. I'm not one of them, okay? And there's no indisputable evidence for or against it yet. There might never be. But it's such an interesting candidate for a theory of everything, a theory of your existence that it's worth at least hearing what it's about. So here it goes. Remember those patterns of vibration of the string, the harmonics, different patterns of vibration of different frequencies. Then imagine that instead of being fixed at the ends, the string ends are allowed to flap around and join them in a loop. But the string still has those same patterns of vibration. Then we increase the tension in the string so that it shrinks. And we increase and increase the tension so that it shrinks and shrinks and shrinks until it's so small that it looks like a point, a particle. String theory says that all of the particles in the universe from the quarks that make the atoms that me and you are made of to the electrons that form the electricity in my amp to the photons of light coming off the lights and even the graviton, the particle that carries the force of gravity. String theory says that all of these different particles are the different harmonics of the same tiny strings, super strings, whose tension 10 to the 39 tons of tension, one with 39 zeros after it, tons of tension, more stress than watching EastEnders, shrinks those strings so small we'd be forgiven for thinking they were just points. Now, a perceptive heckler might say this, hang on, before he pressed his whammy bar down he decreased the tension in the string so the frequency dropped, you all remember that, yeah? So if these strings are so small because they're so tense they've got to be really high frequency. That means they've got to be really high energy because doing something fast takes more energy than doing it slow. Now a clever guy called Einstein said something like energy and mass are equivalent. So if these strings are so small because they're so tense they've actually got to be quite heavy. But electrons aren't heavy and light isn't heavy, it's light. He's talking out of his black hole. The heckler is actually right. If these strings are exactly as I've said they'd each weigh about the same as a bit of dust or a bacterium or something. That's not much, but it's far too much for an electron to be one and far far too much for a photon of light to be one. It's got to be more complicated than that. It is, and here's how. What if these particles are still the vibrations of tiny strings but only the vibrations we can see in our three dimensions while the strings exist in and vibrate in more than three? Remember the hologram? It took three dimensions worth of information and stored it on a two-dimensional surface. What if our universe stores within its three dimensions the information from more? What am I talking about? More than three dimensions. How can you have more than three dimensions? We get by fine with just three, don't we? Left, right, front, back, up, down. What about the other one? If that may be it's because our brains are three-dimensional that we have such trouble even imagining or conceptualising extra ones. We just have to make do with metaphors and analogies. So, I'm going to tell you a story. Once upon a time there were a load of ants who lived on a piece of graph paper. In their perfectly flat world they had no concept of up and down. They just couldn't think of it. One day a sphere fell down under gravity through their flat world leaving a hole. Now this upset the ants quite a lot this hole from nowhere. Most of them were kind of traditionally minded. Let's call them the militants. It gets worse. And they said there can't be an explanation for this. This must be magic. This hole from nowhere. It must be supernatural, inexplicable. But a small minority of the ants who liked thinking in different ways the deviant they liked thinking outside the square please yourselves they said maybe there is an explanation for this a natural explanation. So they looked at the footage which was this. A point had appeared out of nowhere grown into a small disk that disk had expanded to a maximum size then it shrank again to a point and disappeared. And the ants said what if there's such a thing as a three-dimensional circle let's call it a sphere what do you want about ant? Hear me out deck. If this sphere fell through our world we'd only ever see its cross-section so when it touched our plane at its south pole we'd see a point. As the sphere went down and through that point would grow to a disk that disk would go to a maximum size at the equator of the sphere then it would shrink further to a point at the north pole of the sphere and disappear. And we'd say clever ants smarty-pants What if we live in three-dimensional graph paper? Can you do this with me now? Can you fill this huge room with imaginary 3D graph paper lines going left, right, front, back, up, down you've got that in your mind's eye, yeah? What did you do if a point appeared in mid-air? grew into a small ball that ball expanded to a maximum size then shrank again to a point and disappeared. If we were as clever as those ants we might surmise that a four-dimensional sphere a hypersphere had just fallen through our three dimensions. Okay, I'll try again with a diagram. There's a point, a zero-dimensional object imagine if I grab that and I pull it along one dimension I get a line, a 1D object imagine if I grab that and I pull it up along a perpendicular dimension I get a rectangle a two-dimensional shape imagine if again I grab that and I pull it back along another perpendicular dimension I get a cuboid, a 3D shape you can imagine that rotating Imagine if again I grab that and I pull it along another perpendicular dimension I get a four-dimensional cube or hypercube and one of them rotating looks like that Now, I don't know about you but he's sick What the hell is going on there? This is a two-dimensional screen showing a three-dimensional representation of an object rotating in a fourth Just have a chat with your mate what do you think is going on there at all? If you feel you just don't get it, you're looking at me going what the hell is he talking about? Don't worry, everyone thinks exactly the same way even mathematicians are born the same naked apes as the rest of us strangers that might seem No one has an intuitive, immediate grasp of extra dimensions either they just get used to these tricks of the mind, these ways of thinking these mappings so it's just as new to your teachers as it is to you they're sitting there going uh as well don't worry that's an extra big dimension okay string theory says extra dimensions might be quite like that they might be rolled up really tiny within our big three so if you brought back the imaginary 3D graph paper that would mean you're not imagining lines in three dimensions you're actually imagining really really thin tubes in four as though one dimension is rolled up really tiny in fact string theory says we could roll up an extra six or seven tiny dimensions inside our big three if each line wasn't a line but a kind of stack of really weird shapes called calabiow manifold don't ask me what that even represents alright I think you have to have acid on your cornflakes since child ought to understand that kind of math but string theory says if space was shaped like that and the trouble is we don't know which of the many calabiow manifolds describe our space then the vibrations of the tiny strings would look something like our familiar particles so I've kind of pulled a bit of a fast one on you there I've said kind of by magic we can roll up an extra six or seven tiny dimensions inside our big three to give a total of nine or ten but this talks called rock in eleven dimensions anyone tell me a dimension I haven't mentioned yet what's the eleventh what do you think that might be time well done recently did this talk in Belfast got a big chorus of tain it's lovely what if time is like the extra big dimension I was telling you about with the ants and the cube if we treated time kind of like another dimension of space we might say things like next Tuesday or 1066 or the age of the dinosaurs they're all different places in the universe yeah in fact treating time like another dimension of space isn't new at all Einstein's relativity is all about space time all one word as though it's all kind of the same stuff so you might ask what's the shape of space time what's the shape of everything to understand that let's go back to our ants and let's really freak them out by putting them on our 3D world now these are clever ants remember one of them might set off in one direction keep going in one direction keep going all the way around the world Magellant then get back to his original position and go that was weird I kept going in one direction and got back to my original place but they're clever ants they work out the shape of their 3D world even though they're only 2D beings they work out that they happen to live at a certain latitude and if you go more north the earth is less expanded the earth starts as a point at the north pole turns out to the equator then shrinks again to a point at the south pole and that's the earth if the universe is 4 dimensional and that 4th dimension is something like time then just as the ants saw a less expanded earth when they looked north we'd see a less expanded universe when we looked back in time I've dotted the galaxies of the universe on the surface of this balloon if I pretend to look back in time by letting the air out of the balloon you see the galaxies get closer and closer together they're not moving the space between them is contracting until 13 13.7 billion years ago the universe was as small as it could possibly be if you ask the ants why does the earth expand from the north pole kind of look at you a bit funny that's the shape of the world if you ask a cosmologist why does the universe expand from its north pole get a similar answer that is the shape of the universe we seek an explanation for that shape but that's kind of your answer if you ask the ants what north of the north pole they look at you even funny what are you talking about north of north there's no such thing as north of the north pole even if you fly above it in a helicopter it's defined at sea level north and north pole the terms just don't go together logically if you ask a cosmologist what before the north pole of the universe again you might get a similar answer there's no such thing as before time before is a time word there's no such thing as next to space because that would be space as well there's no such thing as outside space time there's no such thing as nothing for a something to come from now I know that batter that kind of batters against your common sense doesn't it I thought so too the first time I started studying physics but Einstein said the common sense is the collection of prejudices you get by the age of 18 so you're not 18 yet there's hope alright the very latest measurements tell us more about the shape of everything we no longer think it's like a four-dimensional sphere which would expand smoothly and then after the equator in future would contract again back to a point we think it's more like this we think near the north pole of the universe there was an enormous expansion called inflation then a smooth expansion and then instead of there being an equator after which the whole thing contracts again we think it's just going to continue to expand at an accelerated rate so is there any evidence for this well the evidence for treating time something like another dimension of space that's basically as well proven anything in science ever is the evidence for the extra tiny dimensions of string theory not at all there might never be definitive evidence one way or the other but we live in an incredible time perhaps even the critical decade imagine that billions of years of evolution to produce a thinking ape billions of those apes living and dying in history in complete bewilderment and ignorance about the nature of their universe and it finally becomes clear in your lifetime what a time to live place to live sorry kind of puts into perspective what those thinking apes usually think about is it you know sport and money and hair it might even happen this year in two weeks time the biggest experiment ever built becomes operational one of the things it's looking for is evidence of extra dimensions but it's looking for an awful lot more as well so show you what it's going to do I'm going to need a load of volunteers how about all of this row all stand up and bring your stress balls bring your stress balls with you let's have all of this row well if you can all stand up and bring your stress balls come on quick quick hurry up stand up stress balls down here right if you can all cluster around this point and face me hurry up and if you can all cluster around this point and face me don't stand in a line just kind of clump together you've all got your stress balls with you yeah right all hold up your stress balls forming these are particles okay these are protons and we're going to form a particle collider so when I say one two three go you're going to accelerate your particles towards me as fast as you can we're also going to need a detector in this case a detective and we're joined by the great Hercule Poirot ladies and gentlemen so hang on so when I say one two three go you're all going to throw your balls at his little Belgian mouth okay so you're not going to throw them at them you're not going to throw them at the cameras you're not going to wait and try and get me in the face as soon as I say one two three go you're going to throw it exactly there you all understand what you're going to do okay one two three go just leave them where they are for a moment what have we got it looks like it's just a random mess of particles but if the detective put in enough effort to see in exactly what kind of particle ended up precisely where he could piece together exactly what had happened during the collision round of applause for our particle accelerators though try and find them if you can't find them I'll just give you another one at the end okay so what were those guys doing they were kind of using their arm like a sling of a certain radius and you can imagine if they had a bigger sling with a bigger radius the particles would have collided at a higher energy now they were just using their arm that bone is actually called the radius it's about 25 centimetres long imagine if the radius of the sling wasn't 25 centimetres but over 4 kilometres this is the large Hadron Collider or LHC it's built in a huge underground tunnel near Geneva in Switzerland that tunnel is filled with 25 kilometres of superconducting magnets cooled by liquid helium that really does make your voice go funny and what the magnets do is they accelerate the protons until they're a few miles on our shore of the speed of light before smashing them into each other at the sight of a vast detector you can see the scale of it this little fella here with the yellow hat on well he's not a little fella he's a normal sized fella but he's in a big thing each beam of protons has the equivalent energy of an intercity train at full speed but it's focused so tightly that it can pass through the zero of a 20 P piece the energy of the resulting collision is extraordinarily vast that it actually recreates the energies right near the north pole of the universe where the entire universe is squeezed into a volume about that big you've all got one of these to take home with you it says on it squeeze the universe so next time you've got a bit of exam stress or you've been typing for a while you feel like the universe is getting you down you can take the entire universe in your hand give it a squeeze and go not so big now are you so what are we hoping to learn from this well we're hoping to learn about this stuff we're made of this stuff called matter now in school you get told a bit about matter I always thought that what you get told in school actually kind of raises more questions than it answers you know you'll be shown something like that and you're told it an atom so if that's a sodium atom that's the smallest bit of sodium you can have and you're told that the word atom comes from the Greek for indivisible you can't subdivide it any further but then you're told that actually yes you can subdivide it further into electrons which orbit a nucleus of protons and neutrons you're even told that the neutrons themselves can further subdivide into a proton and electron during the process of radioactive decay incidentally that's caused by something called the weak force you've heard of the force of gravity you've heard of the electromagnetic force this is the third one for you the weak force so clearly atoms aren't quite as indivisible as their name suggests maybe element units might have been a better name in hindsight something like strings are the true indivisible entities secondly even the very idea of atoms seems kind of inconsistent at school I put my hand up and said miss if opposites attract why don't the electrons just stick to the nucleus and if like charges repel why don't the protons just fly apart and the answer I got was this shut up they just don't basically have to do a physics degree to get the answer to a simple question which is this firstly electrons are just weird alright they only exist at certain energy levels none of which are in the nucleus and they don't move between energy levels they kind of teleport instantly when you look at them they're just bizarre secondly the reason protons don't fly apart is because their mutual repulsion is overcome by a very short range but very powerfully attractive force called the strong force so that's a fourth one for you got gravity, electromagnetic weak and now strong and the particles that feel the strong force are called hadrons hence the name large hadron collider okay we're throwing protons at each other they feel the strong force they're called hadrons there's all the jargon for you sorry about that so we think we understand how three of these forces fit together the electromagnetic, the weak and the strong but the only way we can prove that that theory is correct is by experimentally observing what the theory predicts one of the most important predictions of the theory is called a Higgs field and to understand what that is I'm going to need two volunteers I think those you two were just about there come on down alright if you can both stand out the side of me here alright what I'm going to do if you can stand there that's right what I'm going to do I'm going to hold a brick on a rope and when I say one two three go you're going to grab the brick with one hand and you're going to shake it from side to side as fast as you can you understand both at the same time try not to clash bricks so stand a little bit further apart and neither of you are allowed to say anything okay even though you might be tempted to so we're going to have a brick each just give me a moment so when I say one two three go each going to grab the brick with one hand and shake it side to side go faster faster faster further further faster faster and stop round of applause for our two brick shakers there you can go back to your seats now so what did we learn there well we learned that it's actually it's kind of difficult to shake bricks from side to side and it's definitely difficult to move them upwards look out fake brick bought on the internet best six quid I ever spent real brick real, hang on bought in B and Q yes I did buy a single brick in B and Q so there I'm building a very small wall question for you why was it more difficult to move the real brick because it's heavier it's more massive slightly more difficult question what kind of force or field makes it difficult to move heavy things gravity that's a good guess but wrong you see I was holding up both bricks against gravity no one was doing any work against gravity at all even if we got into space suits and went to the deepest darkest space between galaxies where there is no gravity it would still be difficult to move the real brick modern physics proposes a field like an electromagnetic or gravitational field that creates the entire universe called a Higgs field that gives particles their mass and makes them difficult to move and if we could detect that Higgs field at the LHC physics will have explained why life is so much effort so how do you detect the field well in physics if you're looking for a field you look for a particle associated with it in this case it's called the Higgs boson and if the Higgs boson exists at energy levels it should produce a decay a kind of collision pattern which looks something like that I've also got it on my guitar if you look but that decay pattern is going to be hidden amongst literally billions of other collision patterns so it's going to be a real needle in a haystack job to try and find it the Higgs boson was named after a guy called Peter Higgs it was actually one of my lecturers at Edinburgh University which is just weird this little Scottish bloke I used to see wandering around he might have had the entire universe named after him it's also been called the God particle maybe because it creates matter or creates mass I don't think that's a very good name for it and anyway Peter looks nothing like God really does he so as well as telling us something about matter we're hoping it'll also tell us something about something called antimatter let me tell you that one of the harmonics of the strings was the electron and that they're weird turns out that another of the particles, another of the harmonics is the anti-electron or positron and they're even weirder you see when a positron meets an electron in a process we don't really understand the two annihilate they give nothing but energy then weirder still sometimes you start with nothing but energy and a pair of particles suddenly pops into existence from nothing if you look on your stress balls again you'll notice that the two E's in squeeze forms an electron-positron pair that's because when we squeeze the universe to such enormous energies it should produce a lot of these pairs of particles popping into existence from nowhere for us to study so that's what this experiment is about and that's what science is about really you've got a theory you see what kind of predictions the theory makes then you use experiments to test those predictions that's why astronomers make astrologers wet themselves you see astronomers can predict things like total eclipses to the second whereas astrologers just predict things like you might bump into an old friend today thanks that's why you never see astrologers down the bookies where you've got to be specific and accurate that's why astronomy is called a science but astrology is called what's called a pseudoscience so that's what science is usually about you have your theory you see its predictions but the experiment it's all black and white but sometimes what comes out of the experiment isn't predicted in fact sometimes the biggest revolutions occur when it starts black and white but as the experiment continues you realise that it's so unexpected and revolutionary that it looks like magic Moustache of the Year 1908 this guy, Robert Peary set off on his voyage to become the first person to explore the North Pole and he didn't know what he'd find exactly a hundred years later we're about to explore the North Pole of the universe and we don't know what we'll find either and it's you guys who could be the explorers who make those revolutionary discoveries you see the experiment only starts this year the real task of interpreting the results will peak in six or seven years time when you guys are doing your degree so you could spend your ten grand or whatever on something like a media studies degree where you get to discuss Big Brother and the TeleTubbies for three years before getting a job where you have to wear a baseball cap or you could explore the North Pole of the universe maybe even get a particle named after you and never ever feel like you were wasting that tiny wafer thin slice of space time that you get to call your life and as an added bonus well if you get a job in a baseball cap you get about ten grand a year let's multiply that by a working life of 50 years to give a total of half a million quid say instead if you do agree a degree like physics or engineering or maths or something where you use maths to analyse systems then you should get a good twenty grand a year more than that so finally what I personally find most interesting about this biggest experiment ever is the search for extra dimensions now it's a bit of a long shot but if they find tiny black holes that might mean that gravity at those scales is stronger than we anticipated as though it's kind of leaking in from an extra dimension string theory also predicts things called superpartner particles with specific spins that we can't measure yet but we might one day be able to in future and as a long long shot maybe, just maybe these strings aren't quite as small as I've led you to believe maybe they're just big enough that we could excite them directly and detect them more definitively that would be massive support for the idea that we these incredible biological computers made of stardust are actually holograms of a piece of music being played in eleven dimensions if I didn't know any better I'd say that sounded like a kind of magic I'm Dr. Looney Thank you London Thanks very much