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What Are We Really Made Of?

from Through the Wormhole; That simple question has kept people guessing for thousands of years. In ancient times, the answer was easy, everything in creation was made from one or more of the four elements, Earth... Air... Fire... and Water. When I was a kid, in not quite so ancient times, we were told that everything is made out of atoms. But in the last few decades, scientists have looked inside the atom and found that things are a lot more complicated. Despite all of our knowledge, we still don't understand the true nature of matter. But right now, thousands of investigators are following hunches, tracking down suspects, and getting closer than ever to learning how we and everything around us fits together. And they're doing it by breaking things apart. When I was 6 years old, my father gave me his old pocket watch, a time keeper. "How does this work?" I wondered. I decided to find out. Taking it apart was a lot easier than putting it back together, but I learned a little about what makes things tick. And that's pretty much what particle physicists do today. They smash things up and look at the debris through extremely powerful microscopes. At Chicago's Argon National Laboratory, Bob Stanek builds machines that peer into the subatomic world. Steve Nahn is a Professor at M.I.T. and a team leader on the world's biggest Particle Accelerator, the Large Hadron Collider in Europe. Steve is going to reproduce one of the most important experiments in the history of science, Rutherford's probe into the structure of the atom. This experiment is the same as Rutherford's experiment. We use the same kind of gold foils and send millions of particles through these gold foils. Rutherford thought that all the particles would essentially go straight through and not deflect at all, but that's not what happened. The Rutherford experiment is like firing bullets at a haystack. The particle are like bullets, and the atoms in the gold foil are like haystacks. If the haystack is empty, the bullets go straight through. If the haystack is packed with cannonballs, all the bullets bounce back. If there are a few cannonballs in the center, some of the bullets will bounce back. And that's what happened. When Rutherford fired his particles, most went straight through, but some sharply bounced back from the center of the target, upending the conceived wisdom of the time. Professor Frank Close is a theoretical physicist at Oxford University. Antimatter is a perfect opposite to matter. If I was made of antimatter, I would look exactly the same as I do today. If you looked at the atoms that I'm made of, they would look exactly the same if I was made of antiatoms. It's only when you get inside the atoms that you see the difference. That's the atoms that we're made of have little negatively charged electrons whirling around a big, bulky, positive nucleus. And the antiatoms? Ask this man, Joel Fajans, an antimatter investigator at the University of California, Berkeley. Antimatter is everywhere in the Universe. For instance, this banana contains potassium 40, an isotope of potassium which emits positrons. Positrons and other forms of antimatter are difficult to study, however, and that's my job. That's what I do, is to study antimatter. I was partially inspired to do this by this experiment over here, the Bevatron Accelerator at the Lawrence Berkeley National Laboratory. The Bevatron was the first giant Particle Accelerator. It's not as if we're going to get much better at this than we currently are at it. So you can relax. The world is safe. Antimatter is what we're not made of. But the fact that it exists at all reveals how alien the Universe really is and how little we understand the cosmic forces at work in the heavens and deep inside our own bodies. The discovery of antimatter was followed by deeper probing into the heart of the atom on larger, more powerful Particle Accelerators. But physicists didn't like what they saw. The closer they looked, the less things made sense. The accelerators exposed a bewildering array of mysterious particles, dozens of strains, pieces of matter, all seemingly different. Some were incredibly heavy. Some had no weight at all. The subatomic world earned the nickname "The Particle Zoo." When we were learning about the zoo of particles that were not defined, it was pretty chaotic, and it just didn't look right. You're thinking, "this is bull crap. There's got to be something better than this." 'Cause this is just all, you know, like, just categorizing stuff, black magic, and people just didn't know what they were doing. Physics is a quest for simplicity. This was chaos. Why? To help crack this mystery in the 1970s, the United States built Fermilab, a high-energy research facility 30 miles outside of Chicago. Fermilab sits on top of the Tevatron, a four-mile-long Particle Accelerator. Nobel-prize-winning experimental physicist Leon Lederman conducted many of his experiments here. Today, after years of reading these subatomic tea leaves, physicists feel they are getting closer to answering the question, "what are we really made of?" The stuff that we are made of today only requires maybe a handful of little particles, the atoms on the outside are electrons whirling around like planets, if you like. There's a nucleus in the middle of the atom which we used to believe was made of protons and neutrons. Well, it is, but deeper down, they, in turn, like going to the heart of the cosmic onion, are made of little things called quarks. And two types of quarks, an up quark and a down quark. And that's it. An up and a down quark joined together in different ways ultimately make the atomic nucleus. An electron whirling around the outside make the atom. Throw in a neutrino, which is created in radioactive processes, and that's the basic particles that make up everything that you see around you. There's also the photon of light, which we are seeing with right now, and that pretty well is it. Most of the atoms in our body are made of nuclei and electrons, and the nuclei themselves are made of protons and neutrons, and the protons and neutrons are made of quarks. And, of course, you say, "what are the quarks made of?" And that's where we're stuck. For the last 40, 50 years, we've been studying the quarks, trying to find something inside, and we get the same results we had for the electron. There's nothing inside. The quarks don't have any size. The size, the radius of a quark is zero. It's a little bit like "Alice in Wonderland." Remember when Alice saw the Cheshire cat sitting on the branch of a tree with a big smile? And much to Alice's great astonishment, right in front of her eyes, the Cheshire cat started to disappear, and finally, poof!, It was gone. But it left behind one component, its smile. That quark smile is a tiny box stuffed full of energy. All matter is actually made of energy that has congealed into particulate form. So that appears to be what we are made of, at least as far as we can see right now. But knowing this opens up an even greater mystery, which is, why does the stuff we are made of behave the way it does? Our explorations of matter reveal that everything is nearly hollow, you, me, and everything in the Universe. It's all an empty space with a few pinpricks of matter floating in a void like rocks adrift in the vastness of space. But how do these pinpricks of matter form into shapes and structures? There must be something holding it together, some sort of glue in the ocean of emptiness. The question is, what? Today, we think we know what we're made out of, the incredibly small building blocks that form all the matter in the Universe. But finding these bits and pieces of matter revealed another even more challenging mystery, why are things solid? Why do they have mass? Matter is mostly eupty space. Every now and then, you find the point of an atom, but most of the time, it's empty space. So, that point of atom and that point of atom and so on, how are they held together? How are you held together? How am I held together? It's not glue. You know it's not glue. It has to be some exchange of fundamental properties. That exchange of forces has to happen, even though you don't see it, has to happen at the global level everywhere. Empty space isn't empty at all. It's filled with forces. When these men toss this basketball back and forth, they're transferring the momentum of the ball from one to the other, which pushes them apart, a complex exchange of invisible forces talking to each other. So, there are four fundamental forces, the gravitation force that everybody knows about, the electromagnetic force, which mostly everybody knows about, the weak force, which you don't know about, and the strong force, which you don't know about. The weak force is what determines radioactive decay. How uranium decays into whatever it decays into, that's governed by the weak forces. The strong forces are what holds the proton together, what holds the quarks into three pieces that form a proton. So, us guys are doing the weak forces and the strong forces, and what we don't understand is the gravitational force, and we think we understand the electromagnetic force. Just as we can't see the things we're made of, we can't see the fundamental forces around us. But we know they're there. Finding out how these forces work and where they came from in the first place is the great quest of modern physics. Solving this mystery could reveal the Universe's most closely held secrets, not just what we're made of, but why the stuff inside us holds its shape. The key breakthrough in particle physics was the discovery that certain particles are actually force carriers. Meet Peter Higgs, an unassuming Professor who set off one of the largest and most expensive investigations in the history of science. There was a gapping hole in the Standard Model of the Universe. Peter Higgs put a plug in it. Higgs theorized that a vast field stretching to infinity runs through everything. When certain kinds of particles interact with the field, that interaction is what gives those particles mass. If Higgs' theory becomes fact, we may finally understand why things are solid. But at first, Higgs had trouble getting his theory accepted. A paper outlining the idea was rejected by CERN. I was indignant, because I thought what I'd done had possibly important consequences. So I rewrote the paper by adding on some extra paragraphs, and instead of sending it back to Geneva, where I thought the people at CERN didn't understand what I was talking about, I sent it across the Atlantic to Physical Review Letters, the corresponding American journal, and it was accepted. The paragraphs Higgs added predicted that the mass-giving field would have a matching particle, a force carrier called a Higgs Boson. And this matching particle could theoretically be created in a Particle Accelerator. Gradually, experimental physicists became excited by Higgs' idea. What happens with a theory is, of course, a small number of theorists push this idea. They love it. And little by little, more and more theorists climb on board, you know? It's like the train. "Whoo Whoo!" We're gone, and we're taking off from the station. In one of the great ironies of modern science, CERN, the organization that rejected Higgs' paper, has just spent $10 billion building a machine to find the Higgs particle. But what exactly is the Higgs? Ask a half dozen physicists, and you'll get a half dozen different answers. The Higgs. It's a tricky thing to come up with an analogy for Higgs Bosons. It's, there's the analogy with something being dragged through treacle, but for me, that's misleading, because this is a dissipation of energy, and it isn't like that. That's a pretty bad analogy for the Higgs. What I've read on the Higgs is, in my mind, very confusing. So, what we're doing is re-creating in the lab the first moments of the Universe, and then by surrounding the site of the collisions with these special cameras, detectors, we can record what happened. And so we are simulating just after the big bang, making mini bangs, if you like, in the lab. And from what we find there, we begin to get a sense of how matter, the stuff that we ultimately, 15 billion years later, are made of, first came to be. Jon Butterworth is a physicist at the University College of London. Adam Davison is a postdoctoral student. They're two of the 6,000 scientists conducting experiments back at CERN, the European organization for nuclear research. CERN itself is quite, yeah, is not terribly pretty. It looks like someone dropped a load of rusty bricks on the ground. I get the impression that there was never much of an architectural plan for CERN. Until you go underground, of course, and then it's like something out of a James Bond villain set. This, as a piece of engineering, is a miracle. It is the pyramids of our time. The heart of CERN is the Large Hadron Collider, a $10 billion, 17-mile-long Particle Accelerator. It is quite possibly the most sophisticated scientific instrument ever built. The LHC creates the primordial explosions, then four enormous detectors along the accelerator ring take pictures of the collisions. The two largest detectors are called Atlas and CMS. M.I.T.'S Steve Nahn leads a team that helped design and now runs the CMS detector. We build our detectors to take pictures of the events which happen once every 25 nanoseconds. That's 40 million times a second we have an interaction that we want to take a picture of. And our detector is made out of several different cameras. You could think of it as having, like, an X-ray camera and an infrared camera and an ultraviolet camera and a regular photo camera all at the same time taking pictures of different aspects of the event. So, with this terabytes and terabytes of data on disk, we have to write algorithms which sift through and find that event, that one in 10 million, one in 100 million, one in a billion event that you're looking for. On the other side of the LHC, Butterworth and Davison have developed a way to comb through the enormous amounts of data generated by CMS's archrival, the Atlas detector.


  What Are We Really Made Of? Find answers from scientists Bob Stanek, Steve Nahn, Frank Close, Joel Fajans, Leon Lederman, Peter Higgs, Jon Butterworth, Adam Davison
 
Bevatron Accelerator at the Lawrence Berkeley National Laboratory
Bevatron Accelerator at the Lawrence Berkeley National Laboratory


The subatomic world earned the nickname The Particle Zoo
The subatomic world earned the nickname The Particle Zoo


Tevatron, a four-mile-long Particle Accelerator
Tevatron, a four-mile-long Particle Accelerator


The heart of CERN is the Large Hadron Collider
The heart of CERN is the Large Hadron Collider
  The two men are trying to create maps of what they think the subatomic Universe looked like just seconds after its creation, then matching their imaginary maps up to reality. Somewhere in there, they hope they'll find the Higgs. It's kind of like a border around an unknown country. And we know that it's there. We've had experiments that have gone to high enough energy to tell us there is a border and there is a land beyond it, but we've not had really much of a glimpse of the land. September 2008. The physics world holds its collective breath as the LHC powers up for the first time. The first low-powered beams shoot through the 17-mile ring, and all is well. They're ready to tear the veil off the Universe and try to catch sight of the Higgs. Now they raise the power, one more notch on the way up to 7 trillion volts. And then the LHC explodes. September 2008. Explosions rip through the 17-mile-long tunnel housing the Large Hadron Collider, Europe's Big-Bang machine. An enormous blast destroys hundreds of the superconducting magnets that shoot protons through the accelerator. It was pretty dramatic. Yeah, absolutely. It took a year to fix. It must have been quite an electrical arc to melt through the, imagine the face of the guy who opened the door to the tunnel. Yeah, I can imagine waiting to get in there right then. He must have been really, really nervous to see what had happened.     You know, it was desperately disappointing for everyone involved. As CERN rebuilds its broken magnets, Fermilab's Tevatron steps up the pace. But they don't see the Higgs. What would be more exciting is, in fact, we find things that we don't understand. So, we understand that the Higgs is gonna be there, and so we find it, so, hurray, hurray. Now what do we do? But if you find something you don't understand, well, now people have a job. My job every day is to go to work and understand things that I don' understand. If I have more stuff to no understand, that's job security. So, what are we really made of? Dig deep inside the atom, and you will find tiny particles held together by invisible forces in a sea of empty space. Dig even further, and we discover that everything is made up of tiny packets of energy born in cosmic furnaces. This energy that cools down gets dragged through a mysterious force named the Higgs and clumps together, forming all the things we call matter. It has an evil twin called antimatter, but most of that has long since disappeared. As we get closer to re-creating the heat of the big bang in our accelerators, we get closer to understanding how and why all this happened. Perhaps some day not long from now, we'll finally solve the last remaining riddles of matter and fully comprehend the inner workings of creation.
List with pictures of the scientists, in order of their appearance in Through the Wormhole What Are We Really Made Of? documentary, who share us their knowledges:
Bob Stanek
Bob Stanek (Chicago's Argon National Laboratory)
  Steve Nahn
Steve Nahn (professor at M.I.T.)
  Frank Close
Frank Close (physicist at Oxford University)
  Joel Fajans
Joel Fajans (University of California, Berkeley)
  Leon Lederman
Leon Lederman (Nobel prize winning experimental physicist)
  Peter Higgs
Peter Higgs (theoretical physicist, University of Edinburgh)
  Jon Butterworth
Jon Butterworth (physicist, University College of London)
  Adam Davison
Adam Davison (postdoctoral student, one of 6,000 scientists from CERN)