Present at the Future

by Ira Flatow

  “That problem is an impossible one to make go away by building on top of the Internet, because there’s already access to the underside of the Internet [so] that you can still send those packets. And so if all you can provide [is to] enhance services on top, it’s very difficult to correct something that’s inside,” says Peterson.

  “There’s always this debate,” says Wu, “as to whether things can be improved on top of the Internet or whether you have to rip up the highway and fix it that way.” Wu says it’s not wise to rip it up and start over. The Internet’s original, very simple design has a lot of utility left in it. “I’ll give you one example. When I worked in the telecom industry, no one ever thought the Internet would be useful for phone service, for dialing people up. Everyone thought, It’s just a lousy design; it’ll never be useful. But with the right amount of bandwidth, companies like Skype and other [Voice over Internet Protocol] companies have been very successful. It’s really surprised a lot of engineers.

  “Sometimes it’s very hard to improve on simplicity. I’m not a security expert, and I think maybe security [like cyber attacks] is one area where it’s hard [to improve]. But it has been surprising: video, voice, blogging, search engines, all these things have been built on top of a very simple design, which just says keep the Internet dumb and let the intelligence run at the edges.”

  CHAPTER TWENTY-SEVEN

  THE UNIVERSE AS COMPUTER

  If quantum mechanics were a singer it would be James Brown. Quantum mechanics is the James Brown of sciences.

  —SETH LLOYD

  What is the ultimate computer? The biggest, baddest calculating machine we could ever produce? When futurists talk computers, they inevitably focus on the computer of their dreams (drumroll, please): the quantum computer.

  And they have a good model of just how powerful such a computer could be: the universe itself.

  Yes, believe it or not, “the universe is computing,” says Dr. Seth Lloyd, professor of quantum mechanical engineering at MIT and author of Programming the Universe: A Quantum Computer Scientist Takes on the Cosmos. From the very beginning of time to the present day, the universe has been creating itself in much the same way that a quantum computer works. “These little tiny quantum fluctuations that tell the universe to do this or that say, ‘Let’s form a galaxy here, or let’s split this piece of DNA here over in this other place’—these little accidents programmed the universe.

  “And it’s this process of programming the universe with quantum fluctuations that gives rise to the computation we see around us, which produces all sorts of complexity and structure and beautiful things and horrible things, and most of all, amazing things.”

  HACKING THE UNIVERSE

  Lloyd’s understanding of the universe as a quantum computer stems from building tiny laboratory quantum computers for almost a decade and “coaxing individual atoms and photons to store bits and to compute and watching them work their magic. And in doing that, I realized that essentially, not only the atoms that we’re trying to build quantum computers out of but [also] every single atom out there, and every photon, every electron, every elementary particle carries with it bits of information. And whenever they collide or bonk off of each other, those bits flip. So the universe is actually already computing, and it’s storing information in the microscopic motions of everything—the vibrations of the air, the vibrations of radio waves—and every time those vibrations change or those bits flip, the universe is computing. That’s why we can build quantum computers. We’re actually hacking into the ongoing computation that the universe is performing.”

  Only a physicist—or should I say “ultimate geek”?—would brag about hacking the universe. Lloyd says that if we can just get a handle on how all these calculations are made by the universe, how to coax the molecules and atoms and photons of our universe, how the universe did that to make everything that we have now—we’ll understand much more about computers and maybe even be able to build a giant quantum computer someday for ourselves.

  “In fact, in order to understand the way in which the universe computes, we actually have to build quantum computers. If you talk to them very nicely and ask them very politely, essentially by shining radio waves on them, you can get those bits to flip and to perform computations. But you can’t make them compute unless you understand very well how nature is computing already.”

  The idea that every atom in the universe registers bits of information dates back into the latter part of the nineteenth century. “This was a discovery made by the great statistical mechanisms [of ] James Clerk Maxwell in Cambridge and Edinburgh, Ludwig Boltzmann in Vienna, and Josiah Willard Gibbs at Yale—they came up with the formulas to describe this funky quantity called entropy. Which, till then, had been known as merely something that stuck up the wheels of steam engines and caused them to do less work than you might want them to do. They realized that entropy had to do with the microscopic motions of atoms and molecules, and, phrased in modern terms, the formulas they came up with to describe it meant that entropy was the number of bits of information required to describe the motions of these atoms and molecules. And then Boltzmann went and constructed his equation, called the Boltzmann equation, which actually describes how those bits flip when molecules and atoms collide.

  IT’S NOT YOUR AVERAGE PC

  Lloyd’s laboratory quantum computers are very crude, made out of about a dozen atoms strung together in a molecule. And they don’t work at all like your PC or Mac. “Quantum computers don’t run Windows yet. In fact they run something more like Linux, a very basic version of Linux.”

  Your PC works by breaking up the information you type in, speak, or put in with your joystick when you’re playing Tetris. “It busts it up into the smallest possible components called bits. A bit is a distinction between a zero or a one, or in a computer, a switch that’s open or closed, or yes or no, on or off, heads or tails. It’s the smallest possible chunk of information. In a conventional computer, a bit can be stored by pouring a bunch of electrons into a bucket called a capacitor.”

  That bucketful of electrons would represent a 1. When you empty that bucketful, the empty bucket would represent a 0. So you’ve switched the bit from a 1 to a 0, the binary language of computing.

  CUE THE QUBITS

  A quantum computer works by moving electrons around too. But instead of a whole bucketful of them, to represent a 1 you just have a single electron. That’s not so strange; it’s just taking the ordinary notion of how a bit is stored in your PC and shrinking it down to the level of a single electron.

  But then something very funky happens next, because quantum mechanics is very weird. It’s very counterintuitive and strange: One of the central counterintuitive features is that an electron can be both here and there at the same time.

  That’s not a misprint. In quantum mechanics an electron can be both here and there at the same time. Don’t ask how; no one knows. Just take it on faith, or rather on science. It’s been tested and proven over and over again to be true. “If quantum mechanics were a singer, it would be James Brown. Quantum mechanics is the James Brown of sciences,” says Lloyd.

  “So if the electron is over here—and that’s one—and the electron over there is zero, then the electron is here and there at the same time, in some funky quantum mechanical sense. That’s a bit that registers zero and one at the same time, a so-called quantum bit, or qubit [pronounced cue-bit].”

  Now how do you make use of that if you don’t know which one it is? Don’t we have to know where the bit or qubit is a 1 or 0 to store data?

  “If only life were so certain, that would be great,” Lloyd says. “In fact, sometimes not knowing what’s going on is helpful. I certainly find that in my own research. And quantum computers use that in a very simple but nice way, but still counterintuitive, to do things classical computers can’t.

  “And a good way to think of this is to imagine what does a bit mean? A bit on its own doesn’t mean anything: zero, one, y
es, or no. It depends on what it does.” A bit may also represent an instruction. “So a bit in a computer could tell the computer [to] add two plus two. Or tell the computer to add three plus one. And if you take a quantum computer and you feed in this funky quantum bit, this qubit that reads zero and one at the same time, then it instructs the quantum computer to do this and to do that at the same time. Say, to add two plus two and to add three plus one at the same time. That’s something no classical computer could ever do.”

  This multitasking—the ability to do many things at the same time—is what gives quantum computing its real power. “The ability to do many things at once allows the quantum computer to explore many, many, many more possibilities than any classical computer could,” says Lloyd.

  BREAKING THE CODES

  And just what do you do with all of this computer power?

  “Code breaking is the killer app of quantum computation,” Lloyd says. Killer app is another geeky phrase, a high-tech rendering of the ultimate computer program—that is, the killer application, the one so good that it does away with all the competition. Get it? We’ll let Lloyd illustrate. “With a relatively small quantum computer with a few tens of thousands or hundred thousands of qubits able to form a few billion operations—which is peanuts for an ordinary computer—you would be able to break all the public key codes that are used, for instance, to send information securely over the Internet. And it’s not surprising that the NSA [National Security Agency] and the CIA [Central Intelligence Agency] and other three-letter agencies are very interested in quantum computers.”

  But wait! How happy am I to hear that a small quantum computer can break all my secure passwords and steal my identity? Not very…

  “Luckily, before you decide that you’re not going to buy your coffee over the Internet anymore, quantum mechanics actually supplies a solution to this problem,” because if you store bits of information as quanta, “you can actually distribute information in a way which is provably secure—or at least it’s guaranteed by the laws of physics themselves. So in order to break these codes, you’d have to mess around or discover new laws of physics.”

  That makes me feel better. I like the laws of nature.

  “So quantum computers not only create problems, at least for the NSA—though I like to think of breaking codes as solving problems—[but] they also provide technological solutions that will allow us, the world, to continue. And in fact, quantum cryptographic systems are available today. If you are willing to write a big enough check, you can buy one for your house and feel very secure indeed.”

  But don’t start writing that check just yet. You might not have a place to put your quantum machine.

  “If you are willing to reinforce your desktop, we could put one on it right now. The ones we have over at MIT look like a giant beer keg cooled with liquid helium to cool the superconductor magnets in them. And snaking out of them are wires that connect us to about a million dollars of electronics.

  “But in fact, because there are many different ways of building quantum computers, and because they’re getting more powerful all the time, and the technologies for miniaturizing the components—just like the technologies for miniaturizing components of regular computers—are advancing, you might be able to get one on your desktop in a decade or two—as long as you don’t mind it doing many things at once rather than one thing.”

  A QUOOGLE IS BETTER THAN A GOOGLE?

  One tool suited to the multitasking tools of quantum computing is a search engine. “I’ve been fooling around with quantum versions of Google, which we would call Quoogle or something like that,” Lloyd says. Imagine how fast that engine might run. Other researchers talk about using quantum computers to create better weather and storm forecasts or model global warming. That brings us full circle, because one task that is truly worthy of the supermuscular computer is understanding the universe, how it evolved and works at its basic and most fundamental scales.

  “To understand what happened in the first few instants of the big bang. To understand what happens when black holes evaporate. To understand what happens when you have complex quantum system–constructed gazillions—that’s another technical term—of atoms or of elementary particles. So with Dave Corey [Ph.D.] at MIT, we’ve constructed these quantum simulators—or you might [even] call them quantum analog computers—because they’re analogs of other physical systems we want to simulate. And we’re able to simulate all sorts of weird quantum effects that you could never capture on a classical computer.”

  Quantum computers “are essentially little laboratories that allow us to create quantum weirdness and explore its features,” Lloyd says. And the quantum world is certainly full of weird effects. Take something called “spooky action at a distance.” This is not science fiction. Spooky action at a distance is a phrase coined by Albert Einstein for an action that almost defies reality but is common in the quantum world. It occurs when two particles become “entangled” in a quantum way. If you “touch” or change the state of one of the particles, the other particle is changed instantaneously—at the exact same moment—even if the other particle is at the other side of the universe, seemingly—but not actually—violating the laws of the speed of light.

  Quantum computers allow you to explore this weird but real phenomenon. “I recently, together with some other researchers, found that you could use this spooky action at a distance, this funny quantum entanglement, to escape from black holes—assuming you happen to find yourself caught in one,” Lloyd says.

  Good to know that, just in case…

  “So if you have this funky entanglement between the inside and outside of a black hole—which you do because Stephen Hawking showed decades ago that black holes radiate—and, in fact, this radiation that comes out of a black hole is entangled with what’s going on inside the black hole,” then under the right conditions, something that falls into the black hole—a spaceship or TV set, or anything else—might be able to escape in a transformed state. “Indeed, I’ve had several computers that ended their lives as black holes. So you might even be able to use a black hole itself as a computer if you could figure out the right way to program that.” Once again, we’re back to the concept of the universe as a giant quantum computer. But be careful about setting up this experiment. “As this theory has not been tried out in practice, I feel obliged to warn not to try this at home yet. Do not jump into a black hole just now. We can’t guarantee the results,” Lloyd says.

  BEAM ME UP, LLOYD

  But it gets even weirder. This process of escape from a black hole—given that it does work—works by a process familiar to millions of fans of Captain Kirk. “A process akin to quantum teleportation—as on Star Trek. This is something that could easily happen on Star Trek; Kirk is teleported, falls into a black hole, and teleports out at the last moment, before he hits the singularity.” In fact, using entanglement, Lloyd and his colleagues are “looking into the possibilities of teleporting a rubidium atom from one place to another.” That’s a far cry from beaming Kirk down to Vulcan, but it’s a start.

  “That’s a nice feature of quantum computers. They’re a laboratory for exploring quantum weirdness in the universe.”

  Lloyd also views quantum computers as “being kind of poetic. After you’ve talked with atoms for a while and get on their wavelength and learn to listen to what they’re saying back, what they’re saying has a certain strange and unearthly poetry of its own. And, indeed, you might imagine trying to use a quantum computer to compose a poem that says many things at once. Except, in fact, poetry often does that. One of the beautiful things about poetry, of course, is that words have many meanings. And so maybe we could say that poetry is already kind of quantum mechanical.”

  When quantum computers become part of everyday life, like your PC is now, how else might it influence the way we see ourselves?

  “Every time human beings have made a new kind of technology or machine, it has always ended up transforming human beings in
ways that were unexpected and very hard to predict. As a scientist and a quantum mechanic, for me one of the most remarkable machines was the clock,” Lloyd says. “When clocks were first invented, they had a huge effect on how people saw the world. And they began to see the world as if it were clockwork. And although that sounds kind of silly now—the world is clockwork—this mechanistic view of the universe, the idea that it’s a machine, was extremely powerful, and indeed, you can think of it as a basis for all science. Particularly looking at biology right now, which is uncovering the mechanistic mysteries of cells.

  “So I actually think that in learning to view the universe not just as a machine but [instead] as an information-processing machine, and specifically as a quantum information–processing machine, we’re likely to see the world very differently and come to new understandings of it. And I don’t know what those understandings are going to be.

  “For me, those understandings count for a better understanding for, you know, how to build quantum computers, and how to make them compute. And then maybe also we can understand things about how life began or how the universe became so complex by looking at quantum computation.”

  When may quantum computing become more than a laboratory curiosity?

  “I think that these giant quantum computers that are going to break these codes and strike fear in the hearts of the NSA are a decade or two away, at the earliest. It’s very hard to predict technological progress. I think that it’s far too early, for instance, to start some kind of mini Manhattan Project to build these. I think we’ll be better off having, sharing openly our scientific advances with other scientists around the world to build them.

  “However, these quantum simulators that can simulate chunks of the universe and that can construct new understanding of how complex quantum systems can behave, we can build simple versions of those already, ones with a few billion billion atoms, and investigate the properties of matter.