NOVA scienceNOW: July 10, 2007PBS Airdate: July 10, 2007 NEIL DEGRASSE TYSON (Astrophysicist, American Museum of Natural History): On this episode of NOVA scienceNOW, physicists are revving up for a landmark event. PETER FISHER (Massachusetts Institute of Technology): It's a big step, this is a big time. NEIL DEGRASSE TYSON: They're about to turn on the world's largest machine... MEENAKSHI NARAIN (Brown University): We may find things which nobody has ever thought of. NEIL DEGRASSE TYSON: ...in their quest to find out exactly what the universe is made of. PETER FISHER: It's just a voyage of discovery. TEJINDER VIRDEE (CMS Deputy Spokesperson, CERN): Mind-boggling. NEIL DEGRASSE TYSON: Mind-boggling and mysterious as the synchronized movements of flocks of birds, schools of fish, and even crowds of humans. JOHN HOLLAND: Behavior of the whole is more than the sum of the parts; and that's the flag for emergence. NEIL DEGRASSE TYSON: Could the science of emergence unlock the secrets of intelligence? Even the origins of life itself? ROBERT HAZEN (Carnegie Institution of Washington): This whole concept gives us a whole new way of thinking about the universe. NEIL DEGRASSE TYSON: Also, why are these fruit flies being rolled, bumped, tormented, on a machine called the Deprivator? It's all in the name of sleep research. MATTHEW WILSON (Massachusetts Institute of Technology): Sleep is an enigma. What is its purpose? That's something that we do not understand. NEIL DEGRASSE TYSON: But new studies indicate that one purpose of sleep may be to help us learn, that while we snooze, our brains replay memories, maybe even editing and enhancing them. ROBERT STICKGOLD (Beth Israel Deaconess Medical Center): The brain is being modified while we sleep, so that when we wake up in the morning, in some way, we have a different brain. NEIL DEGRASSE TYSON: All that and more on this episode of NOVA scienceNOW. Major funding for NOVA scienceNOW is provided by the National Science Foundation, where discoveries begin. And, discover new knowledge: biomedical research and science education. Howard Hughes Medical Institute: HHMI. Additional funding is provided by the Alfred P. Sloan Foundation to portray the lives of men and women engaged in scientific and technological pursuit. And the George D. Smith Fund. Major funding for NOVA is also provided by the Corporation for Public Broadcasting, and by PBS viewers like you. Thank you. SLEEPNEIL DEGRASSE TYSON: Hello. I'm Neil deGrasse Tyson, your host for NOVA scienceNOW. We all know that dreams can be, dreams can be a little weird, sometimes filled with bizarre events that would never happen in real life. Nobody really knows why we dream. In fact, nobody really knows why we sleep. Here are some folks who are trying to figure it out. Amita Sehgal likes her flies, fruit flies, to be precise. AMITA SEHGAL (University of Pennsylvania and Howard Hughes Medical Institute): I do have a genuine affection for them. NEIL DEGRASSE TYSON: But sometimes, she has a strange way of showing that affection—especially, when she puts them into this thing. AMITA SEHGAL: We use this piece of equipment we call "The Deprivator." NEIL DEGRASSE TYSON: The Deprivator? It's like riding a roller coaster during an earthquake. What's interesting to Sehgal is what the flies do after spending a whole night in here. The flies on the left were undisturbed last night, and they look fine. But the flies on the right, they were jostled all night long in the Deprivator. Now, some of them look dead, but they're not. According to Sehgal, they're catching up on lost sleep. AMITA SEHGAL: If we keep flies awake at night, they need to make up for the sleep they have lost, and so will sleep in the morning, at a time when they're normally active. NEIL DEGRASSE TYSON: But why would flies need to sleep? Could it be for the same reason we need to sleep? Maybe. But if you ask an expert what exactly that reason is... MATTHEW P. WALKER (Harvard Medical School): We actually know very little about what sleep is doing for the brain. AMITA SEHGAL: We spend a third of our lives sleeping. If you don't sleep, you die. MATT WILSON: Sleep is an enigma. What is its purpose? That's something that we do not understand. NEIL DEGRASSE TYSON: Looks like a waste of time. But then why would so many creatures do it? MATT WILSON: Sleep is something that, the more we look at it, the more we see that it is fundamental. It's fundamental to essentially all organisms. NEIL DEGRASSE TYSON: Including, it seems, organisms like fruit flies. When they're not being knocked around all night, Amita Sehgal's flies follow a pretty familiar schedule. AMITA SEHGAL: They're active during the day and they sleep at night, for the most part, although there is an afternoon siesta as well, especially in males. NEIL DEGRASSE TYSON: Trying to pinpoint the reason for a fly to snooze up to 12 hours a night, Sehgal's lab studies the fruit fly's brain. AMITA SEHGAL: What we were doing was trying to figure out which part of the fly brain was important for sleep. NEIL DEGRASSE TYSON: Sehgal's experiments pointed to the mushroom body, a part of the brain found in creatures like insects and spiders, but not in humans. Biologists have known about the mushroom body for years, but they associated it, not with sleep, but with something else entirely, an insect's memory. AMITA SEHGAL: There is, then, this structure in the fly brain, which we already knew was required for memory, and we now find that it controls sleep. NEIL DEGRASSE TYSON: The finding's intriguing because, for a long time now, sleep researchers have been debating a possible connection between sleep and memory. Bob Stickgold has been looking into this possibility, sometimes in unconventional ways. For him, video games are research tools that can help reveal how our brains learn. ROBERT STICKGOLD: Do you remember when you first started playing Tetris®... NEIL DEGRASSE TYSON: Oh, yeah. ROBERT STICKGOLD: ...that you went to bed at night, and you lay in bed, and you closed your eyes, and you saw little Tetris pieces floating around in front of your eyes? NEIL DEGRASSE TYSON: How did you know that? How did you know that... ROBERT STICKGOLD: Because... NEIL DEGRASSE TYSON: ...I dreamed Tetris shapes? ROBERT STICKGOLD: ...because everybody does. NEIL DEGRASSE TYSON: After taking a few rides on a ski machine, Stickgold's research subjects fall asleep, and then he promptly wakes them up. ROBERT STICKGOLD: If we wake you up just two or three minutes after you fall asleep and ask you, "Neil, what's going through your mind?" You'll say, "Seeing those suckers somersaulting down when I crash." NEIL DEGRASSE TYSON: And why would I dream of this embarrassing moment? Stickgold is convinced that while you sleep, your brain is reviewing what you've learned and strengthening your memories. ROBERT STICKGOLD: The brain is being modified while we sleep, so that when we wake up in the morning, in some way, we have a different brain. And it's a brain that functions better. NEIL DEGRASSE TYSON: At least it seems to function better on some kinds of memory tasks. Recent studies show that after a single night's sleep, sometimes even after a nap, we can do a better job recognizing visual patterns and even solving some math puzzles. MATTHEW WALKER: What we're going to have you do is try and type out a short, five-digit sequence. NEIL DEGRASSE TYSON: I saw it first hand when I took a simple typing test, typing a string of five numbers over and over again as fast as I could. After a night's sleep, I could suddenly type the numbers faster and more accurately. And research backs this up. Most people improved their typing by about 20 percent after sleep. MATTHEW WALKER: Practice doesn't make perfect. It seems to be practice with a night of sleep that makes perfect. Sleep is enhancing that memory so that when you come back the next day you're even better than where you were the day before. NEIL DEGRASSE TYSON: But exactly how could sleep enhance your memory? We don't know. But possible clues have been showing up, not just in the brains of flies, but in the dreams of rats. MIT researcher Matt Wilson says he can read rats' minds, including their dreams, with tiny electric probes. MATT WILSON: What it means is that we're able to, at any time, plug in our electronics, and... NEIL DEGRASSE TYSON: Figure out what they're thinking. MATT WILSON: ...read their, read their mind. NEIL DEGRASSE TYSON: Wilson's mind-readers are actually thin wires, about a tenth of the width of a human hair, that pick up the electrical signals among dozens of brain cells. The wires—painlessly implanted in the rat's brain, and held there by a kind of hat—carry the signals right into Wilson's computers. That information comes up back through these connectors into your computer, and you're sitting there watching a map of the thoughts of this rat? MATT WILSON: Exactly. That's exactly right. NEIL DEGRASSE TYSON: It's remarkable. Wilson is most interested in mapping the rat's thoughts in a part of its brain called the hippocampus. Like the fruit fly's mushroom body, the hippocampus of a rat or a human plays an important role in memory, including our sense of space and location. Wilson uses a specially designed rat maze. If the rat follows the right route, he's rewarded with some chocolate syrup. And as he moves through each different spot in the maze in search of his goal, a unique pattern of cells fires in his brain. MATT WILSON: So we can tell where the animal is, simply based upon which cells in the hippocampus are active. That pattern will be unique for a given location in a given environment. NEIL DEGRASSE TYSON: What's amazing is that the same patterns turn up again, even after the rat drifts off to sleep. That's right, Wilson eavesdrops on his rats' dreams. And they aren't about cheese, they're about running the maze. MATT WILSON: So when the animals would go to sleep, we would see these patterns of brain activity that were expressed while the animals were running on the maze, being replayed, in the same sequence, the same order in which they had been experienced. NEIL DEGRASSE TYSON: But the replay wasn't exactly the same as when the rat ran the maze. Sometimes it was like an extreme fast-forward; quick flashes of the experience. MATT WILSON: Now, at the time, you never know what is going to be important and what is not important. So you may re-evaluate or edit those memories to identify the things that were important. NEIL DEGRASSE TYSON: And this fragmented replay wasn't just happening in the hippocampus. Wilson also detected it in the visual cortex, meaning the rats were likely seeing the maze in their sleep. What's more, the visual cortex is part of the larger neocortex, which, in humans, is responsible for, among other things, long-term memory. MATTHEW WALKER: The hippocampus is replaying the events of the day. The hippocampus is almost, sort of, reactivating the memories at night and playing them out to the neocortex. It's almost as though the hippocampus is having a therapy session with the, with the neocortex. And it's almost saying, "Okay, here's what we learned during the day." MATT WILSON: What are rats and what are people doing during sleep? They are processing memory. They are replaying memory. Now, we could ask, "Is this about learning?" And I believe that's exactly what it is about, that animals are, and humans are trying to learn from past experience. NEIL DEGRASSE TYSON: So, the idea here is that the sleeping brain might be reviewing and strengthening new memories it wants to hold on to for the long-term. And it might identify certain goals we want to work towards. Some believe the sleeping brain could lead us to real insights. ROBERT STICKGOLD: We all know about "sleeping on a problem." And sleeping on a problem is when you have a lot of new information and don't know what to do with it, and you can't decide how to interpret it. And so you say, "Let me sleep on it." And, with remarkable success rates, you can wake up the next morning and have an answer to a problem that you couldn't find the answer to the night before. And that's all about processing information, processing memories in the brain. NEIL DEGRASSE TYSON: So could it be that sleeping on it isn't just an old saying but a biological process that consolidates and organizes important information? MATT WILSON: These are pretty big concepts. And they certainly are controversial. The function of sleep, as it relates to learning and memory, that's something that, at this point, remains speculation. We're making a leap. NEIL DEGRASSE TYSON: Not everybody is leaping into bed with this idea. And researchers have a long way to go before they know what sleep is really doing for our brains. But if the speculation turns out to be true, then you'd have to wonder, "What is our 24/7 culture doing to our ability to think straight?" MATTHEW WALKER: Sleep is not just something that we can choose to sort of dabble in every now and again. It's not a luxury; it's a biological necessity. MATT WILSON: My sense is that disruption of sleep is much deeper than simply, you know, robbing us of rest. My guess would be that we lose the opportunity to gain understanding, a deep understanding of our past experience, that what we sacrifice, in a sense, is wisdom. CERNNEIL DEGRASSE TYSON: In the movies, crazy scientists who build time machines are always obsessing about power, like it takes so many jiggawatts of electricity to get the thing to work. Well, a bunch of real scientists have been working for years on one giant experiment, trying to create exotic particles that haven't existed in the universe for 14 billion years, back to the Big Bang itself. Physicist and correspondent David Wark reports that, in a way, it's a giant time machine. Just like in the movies, it's all about energy. DAVE WARK: (Correspondent): You'd never guess that, hidden beneath these French mountains, an army of workers is underground, constructing the biggest and most complex machine on Earth. It's a project that's got physicists around the world brimming with anticipation. PETER FISHER: It's a big step, this is a big time. MEENAKSHI NARAIN: We may find things which nobody has ever thought of, or told us before. STEVE AHLEN (Boston University): It's a real adventure because we don't know if it's going to work. DAVE WARK: The goal of this giant construction project is nothing less than to find the basic building blocks of the universe. MEENAKSHI NARAIN: The basic quest of particle physics is, "What is the world made of? Do we know everything? Do we know all the constituents of matter? Do we have them all?" DAVE WARK: Scientists have already found a whole carnival of subatomic particles that make up the universe. MEENAKSHI NARAIN: List some names. STEVE AHLEN: Matter as we know it today... PETER FISHER: There are protons, neutrons. That's what we're made of. MEENAKSHI NARAIN: The top quark... STEVE AHLEN: ...bottom quark MEENAKSHI NARAIN: The up... STEVE AHLEN: ...and the down quarks. MEENAKSHI NARAIN: ...the charm quark, the strange quark... STEVE AHLEN: There was a time when we just named everything something silly. PETER FISHER: There are pions, kaons... MEENAKSHI NARAIN: ...W-bosons, Z-bosons. PETER FISHER: ...five different upsilon particles...lambdas... STEVE AHLEN: ...gluons for the strong force... PETER FISHER: ...omegas, sigmas. MEENAKSHI NARAIN: ...muons. STEVE AHLEN: Who ordered that? PETER FISHER: And my favorite particle is the tau. DAVE WARK: This panoply of particles is called The Standard Model, and it's our best picture of what the universe is made of. But as dazzling as it is, we know that the carnival is incomplete. There have to be other hidden particles out there, and we need a new experiment to find them. Normally physicists don't get to ride in helicopters, but today we want to see the world's largest experiment, and up here's really the only place you can get a sense of the scale. Below me is the construction site at CERN, a particle physics lab. The new experiment is so big it stretches from the mountains in France, across the border, to the Geneva Airport in Switzerland. That's because the main part consists of a circular tunnel, 16 miles around. The tunnel is home to the world's biggest, most powerful particle accelerator ever, called the Large Hadron Collider or LHC. Because it's so big, LHC will let us probe deeper into the stuff of the universe than we've ever gone before. This tunnel is being filled with giant electro-magnets, and, in fact, you can see some of them on the ground right there. This is my stop. Each tubular magnet costs close to a million dollars, and the LHC will need more than 1,600 of them. So what is this? MARTA BAJKO (Accelerator Technology Group, CERN): This is the magnet; this is the magnet which is inside this big blue tube. DAVE WARK: The magnets are designed to keep those tiny parts of an atom called protons flowing in a narrow beam through the tunnel. When they are all connected together into a ring, the magnets will create a 16-mile racetrack for protons. In the ring, the powerful magnetic fields force the protons to go round in a circle, and each time they go round they get a little kick from an electric field, so they go faster and faster until, eventually, they are traveling almost at the speed of light. MARTA BAJKO: In fact, the particles, they are traveling in these two tubes. In one of the tubes the particles are traveling in one direction, in the other tube in the opposite direction. DAVE WARK: So there's actually two beams of particles, going in opposite directions? MARTA BAJKO: Exactly. Yes. DAVE WARK: One beam going one way and one beam going the other way. And there are two beams because you are going to collide them? MARTA BAJKO: Exactly. DAVE WARK: This is a technique that's familiar to physicists. A proton traveling close to the speed of light, although absolutely tiny, will carry a lot of energy. Two of them traveling in opposite directions will carry twice the energy. Make them collide and most of that energy can be released in a tiny, but powerful explosion. With enough energy, the explosion should create fundamental particles that we've never seen before. If that happens, it'll be in a tiny region smack in the center of a vast underground cavern. This is one of the four places around the ring where the two beams will actually collide. One beam will come from a tiny beam pipe, from the middle of that hole over there, and fly over my head. The second beam comes through that hole over there, and high up over my head, in the middle of the cavity, the two protons will collide. Now, we're colliding two tiny little protons. Why do we need this vast cavern to find out what happens? Well, in order to detect if any new particles have been created in a collision, researchers have to fill this cavern with some of the most complex scientific instruments ever created. The one here is called CMS. This is one end of the vast CMS detector; the whole detector consists of a series of these plates, each one of which is instrumented with thousands of detectors you can see up here. As we move down we see a large number of these which will all be slid together to make the final detector. No space at all is wasted. This big hole looks like a hole in the detector, but in fact the hole in those detectors is filled by these detectors. Different detectors pick up different kinds of particles, and sandwiched together they'll create a single enormous cylinder which completely surrounds the point where the protons collide. That's important because, as the particles fly away from the collision through the detector, they will leave tracks which form a kind of fingerprint. It's by analyzing these fingerprints that scientists should be able to tell if a new particle was briefly created at the moment of collision. PETER FISHER: That's why the experiments are hugely complicated. They have to identify all the things that come out of two protons that hit. STEVE AHLEN: The LHC experiments are by far the most difficult that have ever been done in high energy physics, and maybe any experiment. DAVE WARK: In fact, the experiments are so complicated it takes physicists from dozens of countries to pull them off. LHC TEAM MEMBER 1: I'm from Switzerland.
LHC TEAM MEMBER 2: I'm from Belgium. LHC TEAM MEMBER 3: ...sono Italiana, Toscana. LHC TEAM MEMBER 4: ...France.
LHC TEAM MEMBER 5: ...Japan. LHC TEAM MEMBER 6: ...Austin, Texas. LHC TEAM MEMBER 7: ...Russian.
LHC TEAM MEMBER 8: ...UK. LHC TEAM MEMBER 9: ...California. LHC TEAM MEMBER 10: I'm from Senegal. LHC TEAM MEMBER 11: ...New Jersey. LHC TEAM MEMBER 12: ...Colombia. LHC TEAM MEMBER 13: ...India, from Bombay. LHC TEAM MEMBER 14: ...from Germany. LHC TEAM MEMBER 15: ...Argentina. LHC TEAM MEMBER 16: I'm from Togo, West Africa. LHC TEAM MEMBER 17: I'm from Brazil. LHC TEAM MEMBER 18: And I'm from the Czech Republic. JIM BENSINGER (Brandeis University): You meet people from all over the world. You talk with them; you get their point of view; you exchange ideas. They all tend to be physicists, so it's not that wide, but I find that's exciting. If the rest of the world worked the way we do, we'd have far fewer problems. DAVE WARK: One problem they do have is analyzing the vast mountain of data that the LHC is going to produce, because, when it's running, it'll create about a billion proton collisions a second. And it'll be running 24/7. TEJINDER VIRDEE: We get 40 million megabytes of data created every second. DAVE WARK: Forty million megabytes, 40,000 gigabytes, or that would be 1,000 large discs for your home computer every second. TEJINDER VIRDEE: Yes, it's mind boggling. The amount of data that we are generating in one year is 10 times bigger than all the World-Wide-Web-stored data. DAVE WARK: In fact, the World Wide Web was invented here at CERN to analyze the results of earlier experiments. But the LHC has so much more data, it will need the power of the Web's successor, something called "the GRID." Using millions of computers around the world, the GRID will turn high-speed computing power into just another commodity, like music or telephone service, that, someday soon, everyone will be able to buy online. It's all part of a quest to understand the world in minute detail. One mystery scientists would love to solve is why some of the particles now whizzing around the universe have mass. STEVE AHLEN: The fact is, from a physicist's point of view, from a philosopher's point of view, from an observational point of view, mass is actually quite mysterious. DAVE WARK: In our best theory of matter, the Standard Model, all the really fundamental particles are like photons—the particles of light—in that they have no intrinsic mass. But we know that objects in the real world have mass, and scientists know that particles like protons and electrons also have mass. So where does that mass come from? PETER FISHER: Why do particles have different masses? And why do they have mass at all? Mass is not something that emerges naturally from a theory. MEENAKSHI NARAIN: We basically do not understand why some particles got mass and others didn't. What happened? What gave mass? DAVE WARK: The leading idea for explaining mass is something called the Higgs field, a field which we believe pervades all of space and which the fundamental particles interact with. The Higgs field is like cosmic cotton candy; it sticks to everything. And, according to this idea, it's actually that stickiness that gives particles their mass. If the Higgs field, along with a Higgs particle, really exists, then the Large Hadron Collider should find it. And that would be a triumph for the Standard Model. But since the LHC will take the particle hunt to a whole new level, many physicists are hoping it will uncover types of matter we've never even dreamed of. MEENAKSHI NARAIN: The best case, in my mind: we do not find the Higgs particle, and we find a whole new set of new particles. STEVE AHLEN: I don't really care what we find. You know, I just want to go off there and look at something and see something no one's ever seen before. That's what motivates me. PETER FISHER: It's just a voyage of discovery. It's looking out into the cosmos and trying to see where we fit in it. EMERGENCENEIL DEGRASSE TYSON: Many people think that the laws of nature and the universe tell us that everything breaks down. Things fall apart, energy wanes, living things grow old and die. Yes, we have some good laws which explain all that, but what about the emergence of life? What about the complexity of life? Where do they come from? Are these rare, miraculous developments? Or is this kind of complexity inevitable, following natural laws we just haven't quite figured out yet? Correspondent Carla Wohl went looking for the answer. CARLA WOHL (Correspondent): It is mysterious how a flock of birds or a school of fish move as one, with such grace and coordination, as if there's one brain behind them all or an invisible force at play. An explanation may be found in emergence, a science that tries to explain complex patterns and behavior that arise in the world around us. Some believe emergence may reveal more than just how birds and fish do this, but how we think and how life itself began in the first place. But while many of science's mysteries long have been explained—gravity, we predict with Newton's laws of gravity, and magnetism, through Maxwell's laws—but things like this remain largely unpredictable. JOHN HOLLAND: Emergence, when you first see it, seems mysterious. But then, if I go back and read the papers at the time of Maxwell, electromagnetism seemed very mysterious, too. CARLA WOHL: Let's start with what we do know about emergence. It's an order we might not expect to see. Usually where there is order, there is a leader—a conductor of an orchestra or a general with his army—orders come from the top, and they go down. JOHN HOLLAND: Yeah, and they go down. KEITH STILL (Crowd Dynamics Limited): Top-down order, where you have one brain controlling the functions of the entire group. CARLA WOHL: A leader at the top and many who follow down below: it's just how we expect things to be. So who's in charge here? Him? No. Him? Unh uh. JOHN HOLLAND: There's no conductor; there's no general. ROBERT HAZEN: There's no leader. There's no director that's telling every fish where to go. CARLA WOHL: Well, then what about these birds? KEITH STILL: There's no one in charge of the birds either. CARLA WOHL: So if the order isn't coming from the top down, where is it coming from? JOHN HOLLAND: The organization comes from the bottom up. So, at the bottom, we have these things that are following their own sets of rules, often fairly simple. One is to go in the same direction as the other guys. Another is "Don't get too close, but don't get too far from my neighbors." CARLA WOHL: And perhaps the most important rule: if someone's coming after you, get out of the way. From these simple rules, very complex patterns can spontaneously emerge. JOHN HOLLAND: What we see is a pattern emerging from the bottom up. CARLA WOHL: And so it came to be called "emergent complexity" or simply, "emergence." Of course, different creatures have different rules, but whether ants or wildebeests or this slime mold... JOHN HOLLAND: The behavior emerges from the actions that are controlled by the rules, and behavior of the whole is more than the sum of the parts. And that's the flag for emergence. CARLA WOHL: And you might not have noticed it, but it's not just seen in animals. KEITH STILL: Similarly, with crowds; there are no leaders within certain types of crowds. CARLA WOHL: Crowds of people? We do it just like the birds and fish? KEITH STILL: Movement is happening at a very much subconscious level. You don't think about how to walk, you just do it. CARLA WOHL: Keith Still studies the emergent complexity in crowds. He says these people crossing the street have no idea they're part of a larger pattern. KEITH STILL: As if they're following each other in long conga lines, what happens is that the first individual that finds a gap is being followed by those people that find it easier to follow something that's moving in roughly the right direction than it is to carve their own path through the crowd. CARLA WOHL: So emergence happens with all kinds of living things that move in groups. KEITH STILL: It can be a crowd, it can be a flock of birds, a school of fish. These are all emergent phenomena, when you're getting a large-scale order out of a small-scale interaction. CARLA WOHL: But emergent complexity can be found in non-living things as well. JOHN HOLLAND: Anything I know that exhibits emergence, involves, a lot of, we might call them agents, a lot of individuals or parts. We could call them parts. CARLA WOHL: John Holland's first experience with emergence came from some fairly unsophisticated electronic parts that came together to create something almost intelligent. And he saw it a half century ago with a game of checkers. You used to look at this as child's play, right? JOHN HOLLAND: Yes, I did. CARLA WOHL: I believe it's your move, too, by the way. JOHN HOLLAND: Oh, all right. CARLA WOHL: What changed your mind? JOHN HOLLAND: What changed my mind was my encounter at IBM—this was in the early '50s—I was busy at that time simulating neural networks. CARLA WOHL: Meanwhile, a coworker, Arthur Samuel, was doing something else. JOHN HOLLAND: He programmed the machine to play checkers. And I thought, "Well, what he's doing is interesting, but that isn't anywhere near as deep as simulating neurons." CARLA WOHL: It's checkers, right? JOHN HOLLAND: Yeah, it's checkers. CARLA WOHL: As it turned out Samuel had achieved something far deeper than anyone at IBM expected. JOHN HOLLAND: He programmed the rules, and the machine would move according to the rules. CARLA WOHL: Not only was the computer following the basic rules of checkers, it had another set of rules as well, a strategy to favor moves that might lead to victory. JOHN HOLLAND: Simply by its experience with him and other players, it favored better moves than he did. That machine learned well enough that it could actually beat Samuel himself. With this learning I have emergence. CARLA WOHL: It was emergent because when the computer followed simple rules, something as unpredictable and complex as learning emerged, something—until then—only living things could do. Fifty years later, computers really don't seem to have come all that far. (Film clip from 2001: A Space Odyssey): Good evening, Dave. How you doing, Hal? CARLA WOHL: 2001 has come and gone. (Film clip from 2001: A Space Odyssey): I've wondered whether you might be having some second thoughts about the mission. CARLA WOHL: Computers were supposed to be having conversations with us, thinking for themselves. So why can't they? Holland says that's because there's another important factor in emergence to consider: complexity depends on how connected the parts are to each other. JOHN HOLLAND: Compare the central nervous system, our brain, to a computer. There's a major difference. Each element in a computer, each transistor, contacts, at most, 10 other elements, but in the human brain each individual neuron contacts 10,000 other neurons. CARLA WOHL: So the sheer number of neurons in our brain, as well as the number of connections between them, is what makes our brain so much more complex than a computer. JOHN HOLLAND: I've got billions of neurons and each one touching 10,000 others, so we get the emergence and, maybe—some of us believe that—consciousness is one of the emergent phenomena here. CARLA WOHL: Consciousness? Could something so complex spontaneously emerge from individual parts following simple rules? It may seem counter-intuitive. Many of us think that without a leader or a plan, things become more disordered with time. ROBERT HAZEN: Our intuition about the world is that things deteriorate, we get old, we die. CARLA WOHL: Buildings crumble, we expect decay. ROBERT HAZEN: This is the increase that's inevitable in the universe of disorder. CARLA WOHL: But if order can emerge from disorder, could we actually expect to see something as complex as life itself emerge? ROBERT HAZEN: Many of us believe that life follows inevitably as another emergent complex phenomenon. CARLA WOHL: Bob Hazen, an astrobiologist with the Carnegie Institution is trying to find out if life on Earth emerged from simple molecules arranging themselves into something living. Hazen hypothesizes that the right molecules, under the right conditions will do this, form increasingly more complex structures, and those complex structures will form even more complex structures and so on, until finally you get life. To start he needed a simple molecule. He chose pyruvic acid. ROBERT HAZEN: Pyruvic acid is a good proxy for the kind of simple molecule that would have been abundant on the early Earth. It's colorless, it's basically odorless.
You load it into a gold tube—it's like threading a needle—you then seal this up. CARLA WOHL: Hazen is trying to reproduce the energy of the heat and pressure deep within the Earth. ROBERT HAZEN: Typical conditions that might occur in volcanic zones on the floor of the ocean. Seal this up. CARLA WOHL: He pressurizes and heats the capsules to 250 degrees centigrade. ROBERT HAZEN: Just like a pressure cooker. Emergent complexity takes place in any environment where you have lots of agents coming together, molecules coming together, and energy. CARLA WOHL: And in a week's time he's re-created the heat and pressure. The one thing missing is water. ROBERT HAZEN: That's the magic trick. Put it in water, and bingo! Those molecules self-organize into an enclosure—cell-like structures called vesicles, a structure which is essential for life. CARLA WOHL: So here the agents are molecules. The rules are the rules of chemistry. What emerges is one step closer to something biological, an important first step towards life. ROBERT HAZEN: And the origin of life must have been a sequence of emergent steps from simplicity to complexity. You go from the simplicity of volcanic gases like carbon dioxide and water to organic molecules. CARLA WOHL: Still, a vesicle needs to capture energy and nutrients to grow, replicate and divide, before it can truly be a living thing. And whether these steps are emergent is, for Bob Hazen, the great mystery to be solved. ROBERT HAZEN: This whole concept of emergent complexity gives us a whole new way of thinking about the universe, going from the simplicity of the earliest universe to the complexity of the modern, living world. JOHN HOLLAND: Even Hawking says complexity is the study of the 21st century. Maybe in 20 years it'll be the standard science, for all I know. ROBERT HAZEN: Scientists would love to quantify emergent complexity. We'd love to be able to have a formula that told us what systems become complex, how complex they become. JOHN HOLLAND: My guess is that we will find some laws that will let us describe some things in these complex adaptive systems, patterns that we can recognize and maybe even make predictions about. And that's the great advantage of Newton, of Maxwell. And maybe someday we'll get our own Maxwell. PROFILE: JULIE SCHABLITSKYNEIL DEGRASSE TYSON: Most of us think of the Old West as the stuff of myth and legend and cowboy movies. But the West was made by very real people, and people always leave stuff behind. So if you're willing to get your hands a little dirty, like the archeologist in this episode's profile, you might just discover the real story behind the myth buried beneath the dirt and the sand. JULIE SCHABLITSKY (University of Oregon): We're just about there. And this just might be a little deeper, or perhaps may go down even. NEIL DEGRASSE TYSON: Julie Schablitsky is an historical archeologist with the University of Oregon. JULIE SCHABLITSKY: I feel like I'm a shot-putter. NEIL DEGRASSE TYSON: She's not afraid to get her hands dirty, as she digs for the truth, literally. JULIE SCHABLITSKY: Oooh, looks like an alcohol bottle. Each archeologist that goes off to a site is looking for a story. It's a crown cap, though, so what's the middle mark? Is that C, G together? I can date that here. A story that will tell them something different about the people who used to live there. What does the base of the bottle say? An S? Something that hasn't been known before. "William Franz & Sons 1900-1929. Milwaukee, Wisconsin." So the Holy Grail is not necessarily an object, it's a story. NEIL DEGRASSE TYSON: Julie brings her passion for her science to what was once the site of a 19th century Chinatown, in John Day, Oregon. That's where she's trying to tell the story of the thousands of Chinese laborers who came West in the late 1800s. JULIE SCHABLITSKY: The Chinese were instrumental in building the railroads. They were instrumental in mining. They made shoes; they were cobblers; they cut hair; they were servants in people's homes; they were cooks. Like all immigrant communities you really build a country on their backs. NEIL DEGRASSE TYSON: Yet there are almost no written records from or about the Chinese of that era. JULIE SCHABLITSKY: You don't see them documenting their life in journals. And very seldom do you find even letters that went back and forth between them and their families. So you have this gap of what it was like to be Chinese in 19th century America. Ooh. Yup. It's a single-dose medicine bottle. It's Chinese, umhmm, Chinese, definitely Chinese. And what archeology can do is it can fill in those gaps, and give the voiceless Chinese that voice. NEIL DEGRASSE TYSON: Julie's love of archeology started very early. Her first digs took place on the gravel driveway of her Minnesota home where she grew up. By the time she was seven, this self-assured second-grader was telling her classmates she had found her life's calling. JULIE SCHABLITSKY: Back then, I thought about archaeology as being a lot of the gold idols with the ruby eyes, and mummies, and things from a far away land. And I never realized that archeology could be in your own backyard. NEIL DEGRASSE TYSON: An idea that grew along with her, through elementary school into high school. Even the poster on her bedroom door was of an atypical rock star. JULIE SCHABLITSKY: Ramesses II is not the average teen idol, but I found him quite interesting. NEIL DEGRASSE TYSON: Today her interests have gone beyond the idols and icons and even the physical artifacts themselves. JULIE SCHABLITSKY: We found a coin purse. MARY OBERST: Oh my gosh. Sure enough. JULIE SCHABLITSKY: The bottle that you could pick up, the arrowhead you could hold in your hand, and think that, wow, someone made this—that's what really grabbed my interest. But what held it was that when I began to put these artifacts together and tell a story that was really important. NEIL DEGRASSE TYSON: And that's exactly what Julie helped to do, on a headline-making excavation, involving one of the great and gruesome stories of the Old West: the story of the Donner party, the group of west-bound pioneers who, because of bad luck, an ill-chosen route, and early snows, were trapped in the California mountains for a bitter winter in 1846 to '47. JULIE SCHABLITSKY: So you had a little over 80 people, stranded in the Sierra Nevadas, in two different camps. In both camps, about half the people lived and about half the people died. NEIL DEGRASSE TYSON: Just what the living did to survive horrified everyone who heard the story. Some survivors in the larger of the two Donner party camps admitted they had cannibalized the bodies of those who had already died. JULIE SCHABLITSKY: It seemed that everyone was assured that cannibalism was participated in by every single member of the Donner family party. I think a lot of people believe that they survived by eating each other. NEIL DEGRASSE TYSON: Julie was the co-leader of a team that recently went back to the second camp, to get a fuller story of what really happed there, more than 150 years ago. JULIE SCHABLITSKY: We wanted to know if they cannibalized. We wanted to know, if they didn't cannibalize, how'd they survive? How desperate did they become? What did they eat? NEIL DEGRASSE TYSON: Julie's team discovered a buried hearth and a trove of burned and chop-marked bones. She took those bones, and did what she's become known for: Julie brought in experts from other scientific disciplines, in this case, forensic bone analysts. Their findings? Those chopped, boiled bones were those of hunted deer and rabbit, of their horses, even dog, but no humans. JULIE SCHABLITSKY: These people ate their family dog. They did everything in their power to extract every last nutrient before they did the unthinkable. NEIL DEGRASSE TYSON: Thanks to Julie and her team, about half of the Donner party members at the second campsite were exonerated, correcting the sensationalized stories of the entire Donner party quickly resorting to cannibalism. JULIE SCHABLITSKY: It looks like only several people did participate in cannibalism, and not until the very, very end of their entrapment. So I think that's a real big finding for us. JON ERLANDSON (University of Oregon): I think she's something of an emerging star in historical archaeology. JULIE SCHABLITSKY: Go! NANCY NIEDERNHOFER (Oregon Parks and Recreation Department): One of the things that I love so much about Julie, and I especially enjoy working with her, is the enthusiasm. JULIE SCHABLITSKY: That's way cool. NANCY NIEDERNHOFER: It's so infectious. JULIE SCHABLITSKY: Oh, wait. Oh, my gosh. I think this is a soy s.... It looks like right on top of this board here is a spout from a soy sauce bottle, a Chinese soy sauce bottle. There's no doubt what this is. MARIE POKRANT (Site Volunteer): She is really there to really help in times when your work is...long, hot days, and it's frustrating work. She's still, like, being the cheerleader. NEIL DEGRASSE TYSON: Which in fact she used to be. She's always been active—the volunteer firefighting, snowboarding kind of active. And she says she's always been a tomboy—but the kind that's never been afraid to wear pink, or to poke fun at herself, or try something new. JULIE SCHABLITSKY: Oh, Susanna. There's both the part of me that can be dressed up and feminine, but at the same time can also be a scientist who likes to play in the dirt. And I've always been true to who I am, and I've always been comfortable with being, I guess, a lipstick archeologist, if you will. NEIL DEGRASSE TYSON: But make no mistake, this lipstick archeologist is not someone to be taken lightly. Julie's one of the first archeologists in her field to discover historic period DNA from an artifact. She excavated this glass syringe from a site in Virginia City, Nevada. JULIE SCHABLITSKY: Nowadays forensics and DNA is a household word, and I wanted to understand what the syringe was used for. I wanted to know who used it. Knowing that it came from a 19th century structure just was not enough for me. DNA tests revealed that at least four people had used the syringe to inject an opiate, most likely morphine. They were both men and women used that syringe, and perhaps one of those individuals was from African descent. And I would never have been able to know that just using traditional archaeological methods. And one thing we're not finding is, there are no women's personal items, and that's because we're in a bachelor culture, really. JON ERLANDSON: She's really good at interpreting history for the public. We have to share our findings with them and make it interesting, not just blasé. JULIE SCHABLITSKY: This came all the way from China, back in the late 19th, early 20th century. And it's either from a food storage jar or.... My goal as an archaeologist is not just to dig up the artifacts, put them in a bag and put them in a museum somewhere, but to get that out to the public, people that have an interest in who was here before them. NEIL DEGRASSE TYSON: Julie Schablitsky's commitment to her science is driven by her passion to understand the past, to re-construct history, one artifact at a time. JULIE SCHABLITSKY: Even little bits and pieces from a Chinese trash pit... This is excellent preservation. ...or DNA from a syringe can be brought together to tell a bigger story. Oh, well, good. That's a nice, complete piece. NEIL DEGRASSE TYSON: Julie even married an archeologist: Bob Nyland, an underwater archeologist with the US Navy. JULIE SCHABLITSKY: He's water, I'm land. So he shares my passion. If you really have a drive for something, a desire, this passion that is inside of you, don't ever think, "Oh, I can't do it." I think it's very, very rare that people take a passion that they have, and turn it into a profession. But I think it's completely possible. NEIL DEGRASSE TYSON: And now for some final thoughts on subatomic particles. We learn early in school that there is such a thing as atoms and that all of matter is composed of them. A little later, we learn that atoms—a word, by the way, from the Greek atomos, meaning indivisible—are themselves composed of even smaller particles, the familiar electrons, protons, and neutrons. Under exotic conditions of high energy, like what's common at CERN and in other accelerators, particles wholly unfamiliar to everyday life pop into existence. But what may be unfamiliar to us, is common to the cosmos. Want to find the biggest accelerators of them all? They're out there in the universe: the million-degree cores of stars, the turbulent environments of massive black holes dining on gas clouds that wander too close, or the stupendously hot conditions during the big bang. So while physicists probe ever higher energies to understand the fundamental building blocks of matter, those same experiments serve as a probe of what's going on across space and time. There lies one of the most remarkable stories of modern science: how the study of the smallest constituents of matter offers deep insight to the biggest event there ever was, the birth of the universe itself. And that is the cosmic perspective. And now we'd like to hear your perspective on this episode of NOVA scienceNOW. Log on to our Web site and tell us what you think. You can watch any of these stories again, listen to podcasts, hear from experts, or even take our survey. Find us at pbs.org. That's our show. We'll see you next time. Stay tuned for more about NOVA. But first... Educators and other educational institutions can order this or other NOVA programs, for 19.95 plus shipping and handling. Call WGBH Boston video at 1-800-255-9424. NOVA is a production of WGBH Boston. Major funding for NOVA scienceNOW is provided by the National Science Foundation, where discoveries begin. And... Discover new knowledge: biomedical research and science education. Howard Hughes Medical Institute: HHMI. Additional funding is provided by the Alfred P. Sloan Foundation to portray the lives of men and women engaged in scientific and technological pursuit. And the George D. Smith Fund. Major funding for NOVA is also provided by the Corporation for Public Broadcasting, and by PBS viewers like you. Thank you. 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