Physics of the Future

by Michio Kaku

  Today, if you are in a bad car accident on a lonely road, you could easily bleed to death. But in the future, your clothes and car will automatically spring into action at the first sign of trauma, calling for an ambulance, locating your car’s position, uploading your entire medical history, all while you are unconscious. In the future, it will be difficult to die alone. Your clothes will be able to sense any irregularities in your heartbeat, breathing, and even brain waves by means of tiny chips woven into the fabric. When you get dressed, you go online.

  Today, it is possible to put a chip into a pill about the size of an aspirin, complete with a TV camera and radio. When you swallow it, the “smart pill” takes TV images of your gullet and intestines, and then radios the signals to a nearby receiver. (This gives new meaning to the slogan “Intel inside.”) In this way, doctors may be able to take pictures of a patient’s intestines and detect cancers without ever performing a colonoscopy (which involves the inconvenience of inserting a six-foot-long tube up your large intestine). Microscopic devices like these also will gradually reduce the necessity of cutting skin for surgery.

  This is only a sample of how the computer revolution will affect our health. We will discuss the revolution in medicine in much more detail in Chapters 3 and 4, where we also discuss gene therapy, cloning, and altering the human life span.

  LIVING IN A FAIRY TALE

  Because computer intelligence will be so cheap and widespread in the environment, some futurists have commented that the future might look like something out of a fairy tale. If we have the power of the gods, then the heaven we inhabit will look like a fantasy world. The future of the Internet, for example, is to become the magic mirror of Snow White. We will say, “Mirror, mirror on the wall,” and a friendly face will emerge, allowing us to access the wisdom of the planet. We will put chips in our toys, making them intelligent, like Pinocchio, the puppet who wanted to be a real boy. Like Pocahontas, we will talk to the wind and the trees, and they will talk back. We will assume that objects are intelligent and that we can talk to them.

  Because computers will be able to locate many of the genes that control the aging process, we might be forever young like Peter Pan. We will be able to slow down and perhaps reverse the aging process, like the boys from Neverland who didn’t want to grow up. Augmented reality will give us the illusion that, like Cinderella, we can ride to fantasy balls in a royal coach and dance gracefully with a handsome prince. (But at midnight, our augmented reality glasses turn off and we return to the real world.) Because computers are revealing the genes that control our bodies, we will be able to reengineer our bodies, replacing organs and changing our appearance, even at the genetic level, like the beast in “Beauty and the Beast.”

  Some futurists have even feared that this might give rise to a return to the mysticism of the Middle Ages, when most people believed that there were invisible spirits inhabiting everything around them.

  END OF MOORE’S LAW

  We have to ask: How long can this computer revolution last? If Moore’s law holds true for another fifty years, it is conceivable that computers will rapidly exceed the computational power of the human brain. By midcentury, a new dynamic occurs. As George Harrison once said, “All things must pass.” Even Moore’s law must end, and with it the spectacular rise of computer power that has fueled economic growth for the past half century.

  Today, we take it for granted, and in fact believe it is our birthright, to have computer products of ever-increasing power and complexity. This is why we buy new computer products every year, knowing that they are almost twice as powerful as last year’s model. But if Moore’s law collapses—and every generation of computer products has roughly the same power and speed of the previous generation—then why bother to buy new computers?

  Since chips are placed in a wide variety of products, this could have disastrous effects on the entire economy. As entire industries grind to a halt, millions could lose their jobs, and the economy could be thrown into turmoil.

  Years ago, when we physicists pointed out the inevitable collapse of Moore’s law, traditionally the industry pooh-poohed our claims, implying that we were crying wolf. The end of Moore’s law was predicted so many times, they said, that they simply did not believe it.

  But not anymore.

  Two years ago, I keynoted a major conference for Microsoft at their main headquarters in Seattle, Washington. Three thousand of the top engineers at Microsoft were in the audience, waiting to hear what I had to say about the future of computers and telecommunications. Staring out at the huge crowd, I could see the faces of the young, enthusiastic engineers who would be creating the programs that will run the computers sitting on our desks and laps. I was blunt about Moore’s law, and said that the industry has to prepare for this collapse. A decade earlier, I might have been met with laughter or a few snickers. But this time I only saw people nodding their heads.

  So the collapse of Moore’s law is a matter of international importance, with trillions of dollars at stake. But precisely how it will end, and what will replace it, depends on the laws of physics. The answers to these physics questions will eventually rock the economic structure of capitalism.

  To understand this situation, it is important to realize that the remarkable success of the computer revolution rests on several principles of physics. First, computers have dazzling speed because electrical signals travel at near the speed of light, which is the ultimate speed in the universe. In one second, a light beam can travel around the world seven times or reach the moon. Electrons are also easily moved around and loosely bound to the atom (and can be scraped off just by combing your hair, walking across a carpet, or by doing your laundry—that’s why we have static cling). The combination of loosely bound electrons and their enormous speed allows us to send electrical signals at a blinding pace, which has created the electric revolution of the past century.

  Second, there is virtually no limit to the amount of information you can place on a laser beam. Light waves, because they vibrate much faster than sound waves, can carry vastly more information than sound. (For example, think of stretching a long piece of rope and then vibrating one end rapidly. The faster you wiggle one end, the more signals you can send along the rope. Hence, the amount of information you can cram onto a wave increases the faster you vibrate it, that is, by increasing its frequency.) Light is a wave that vibrates at roughly 1014 cycles per second (that is 1 with 14 zeros after it). It takes many cycles to convey one bit of information (a 1 or a 0). This means that a fiber-optic cable can carry roughly 1011 bits of information on a single frequency. And this number can be increased by cramming many signals into a single optical fiber and then bundling these fibers into a cable. This means that, by increasing the number of channels in a cable and then increasing the number of cables, one can transmit information almost without limit.

  Third, and most important, the computer revolution is driven by miniaturizing transistors. A transistor is a gate, or switch, that controls the flow of electricity. If an electric circuit is compared to plumbing, then a transistor is like a valve controlling the flow of water. In the same way that the simple twist of a valve can control a huge volume of water, the transistor allows a tiny flow of electricity to control a much larger flow, thereby amplifying its power.

  At the heart of this revolution is the computer chip, which can contain hundreds of millions of transistors on a silicon wafer the size of your fingernail. Inside your laptop there is a chip whose transistors can be seen only under a microscope. These incredibly tiny transistors are created the same way that designs on T-shirts are made.

  Designs on T-shirts are mass-produced by first creating a stencil with the outline of the pattern one wishes to create. Then the stencil is placed over the cloth, and spray paint is applied. Only where there are gaps in the stencil does the paint penetrate to the cloth. Once the stencil is removed, one has a perfect copy of the pattern on the T-shirt.

  Likewise, a stencil is made conta
ining the intricate outlines of millions of transistors. This is placed over a wafer containing many layers of silicon, which is sensitive to light. Ultraviolet light is then focused on the stencil, which then penetrates through the gaps of the stencil and exposes the silicon wafer.

  Then the wafer is bathed in acid, carving the outlines of the circuits and creating the intricate design of millions of transistors. Since the wafer consists of many conducting and semiconducting layers, the acid cuts into the wafer at different depths and patterns, so one can create circuits of enormous complexity.

  One reason why Moore’s law has relentlessly increased the power of chips is because UV light can be tuned so that its wavelength is smaller and smaller, making it possible to etch increasingly tiny transistors onto silicon wafers. Since UV light has a wavelength as small as 10 nanometers (a nanometer is a billionth of a meter), this means that the smallest transistor that you can etch is about thirty atoms across.

  But this process cannot go on forever. At some point, it will be physically impossible to etch transistors in this way that are the size of atoms. You can even calculate roughly when Moore’s law will finally collapse: when you finally hit transistors the size of individual atoms.

  The end of Moore’s law. Chips are made the same way as designs on T-shirts. Instead of spray painting over a stencil, UV light is focused on a stencil, burning an image onto layers of silicon. Acids then carve out the image, creating hundreds of millions of transistors. But there is a limit to the process when we hit the atomic scale. Will Silicon Valley become a rust belt? (photo credit 1.1)

  Around 2020 or soon afterward, Moore’s law will gradually cease to hold true and Silicon Valley may slowly turn into a rust belt unless a replacement technology is found. According to the laws of physics, eventually the Age of Silicon will come to a close, as we enter the Post-Silicon Era. Transistors will be so small that quantum theory or atomic physics takes over and electrons leak out of the wires. For example, the thinnest layer inside your computer will be about five atoms across. At that point, according to the laws of physics, the quantum theory takes over. The Heisenberg uncertainty principle states that you cannot know both the position and velocity of any particle. This may sound counterintuitive, but at the atomic level you simply cannot know where the electron is, so it can never be confined precisely in an ultrathin wire or layer and it necessarily leaks out, causing the circuit to short-circuit.

  We will discuss this in more detail in Chapter 4, when we analyze nanotechnology. For the rest of this chapter, we will assume that physicists have found a successor to silicon power, but that computer power grows at a much slower pace than before. Computers will most likely continue to grow exponentially, but the doubling time will not be eighteen months, but many years.

  MIXING REAL AND VIRTUAL REALITY

  By midcentury, we should all be living in a mixture of real and virtual reality. In our contact lens or glasses, we will simultaneously see virtual images superimposed on the real world. This is the vision of Susumu Tachi of Keio University in Japan and many others. He is designing special goggles that blend fantasy and reality. His first project is to make things disappear into thin air.

  I visited Professor Tachi in Tokyo and witnessed some of his remarkable experiments in mixing real and virtual reality. One simple application is to make an object disappear (at least in your goggles). First, I wore a special light brown raincoat. When I spread out my arms, it resembled a large sail. Then a camera was focused on my raincoat and a second camera filmed the scenery behind me, consisting of buses and cars moving along a road. An instant later, a computer merged these two images, so the image behind me was flashed onto my raincoat, as if on a screen. If you peered into a special lens, my body vanished, leaving only the images of the cars and buses. Since my head was above the raincoat, it appeared as if my head was floating in midair, without a body, like Harry Potter wearing his invisibility cloak.

  Professor Tachi then showed me some special goggles. By wearing them, I could see real objects and then make them disappear. This is not true invisibility, since it works only if you wear special goggles that merge two images. However, it is part of Professor Tachi’s grand program, which is sometimes called “augmented reality.”

  By midcentury, we will live in a fully functioning cyberworld that merges the real world with images from a computer. This could radically change the workplace, commerce, entertainment, and our way of life. Augmented reality would have immediate consequences for the marketplace. The first commercial application would be to make objects become invisible, or to make the invisible become visible.

  For example, if you are a pilot or a driver, you will be able to see 360 degrees around yourself, and even beneath your feet, because your goggles or lens allow you to see through the plane’s or car’s walls. This will eliminate blind spots that are responsible for scores of accidents and deaths. In a dogfight, jet pilots will be able to track enemy jets anywhere they fly, even below themselves, as if your jet were transparent. Drivers will be able to see in all directions, since tiny cameras will monitor 360 degrees of their surroundings and beam the images into their contact lenses.

  If you are an astronaut making repairs on the outside of a rocket ship, you will also find this useful, since you can see right through walls, partitions, and the rocket ship’s hull. This could be lifesaving. If you are a construction worker making underground repairs, amid a mass of wires, pipes, and valves, you will know exactly how they are all connected. This could prove vital in case of a gas or steam explosion, when pipes hidden behind walls have to be repaired and reconnected quickly.

  Likewise, if you are a prospector, you will be able to see right through the soil, to underground deposits of water or oil. Satellite and airplane photographs taken of a field with infrared and UV light can be analyzed and then fed into your contact lens, giving you a 3-D analysis of the site and what lies below the surface. As you walk across a barren landscape, you will “see” valuable mineral deposits via your lens.

  In addition to making objects invisible, you will also be able to do the opposite: to make the invisible become visible.

  If you are an architect, you will be able to walk around an empty room and suddenly “see” the entire 3-D image of the building you are designing. The designs on your blueprint will leap out at you as you wander around each room. Vacant rooms will suddenly come alive, with furniture, carpets, and decorations on the walls, allowing you to visualize your creation in 3-D before you actually build it. By simply moving your arms, you will be able to create new rooms, walls, and furniture. In this augmented world, you will have the power of a magician, waving your wand and creating any object you desire.

  Internet contact lenses will recognize people’s faces, display their biographies, and translate their words as subtitles. Tourists will use them to resurrect ancient monuments. Artists and architects will use them to manipulate and reshape their virtual creations. The possibilities are endless for augmented reality. (photo credit 1.2)

  AUGMENTED REALITY: A REVOLUTION IN TOURISM, ART, SHOPPING, AND WARFARE

  As you can see, the implications for commerce and the workplace are potentially enormous. Virtually every job can be enriched by augmented reality. In addition, our lives, our entertainment, and our society will be greatly enhanced by this technology.

  For example, a tourist walking in a museum can go from exhibit to exhibit as your contact lens gives you a description of each object; a virtual guide will give you a cybertour as you pass. If you are visiting some ancient ruins, you will be able to “see” complete reconstructions of the buildings and monuments in their full glory, along with historical anecdotes. The remains of the Roman Empire, instead of being broken columns and weeds, will spring back to life as you wander among them, complete with commentary and notes.

  The Beijing Institute of Technology has already taken the first baby steps in this direction. In cyberspace, it recreated the fabulous Garden of Perfect Brightness, which w
as destroyed by British-French forces during the Second Opium War of 1860. Today, all that is left of the fabled garden is the wreckage left by marauding troops. But if you view the ruins from a special viewing platform, you can see the entire garden before you in all its splendor. In the future, this will become commonplace.

  An even more advanced system was created by inventor Nikolas Neecke, who has created a walking tour of Basel, Switzerland. When you walk around its ancient streets, you see images of ancient buildings and even people superimposed on the present, as if you were a time traveler. The computer locates your position and then shows you images of ancient scenes in your goggles, as if you were transported to medieval times. Today, you have to wear large goggles and a heavy backpack full of GPS electronics and computers. Tomorrow, you will have this in your contact lens.

  If you are driving a car in a foreign land, all the gauges would appear on your contact lens in English, so you would never have to glance down to see them. You will see the road signs along with explanations of any object nearby, such as tourist attractions. You will also see rapid translations of road signs.