Physics of the Future: How Science Will Shape Human Destiny and Our Daily Lives by the Year 2100

discarded, replaced by the motion of electrons in this gigantic computer. In this picture, our ultimate destiny is to wind up as lines of code in this vast computer program, with all the apparent sensations of physical bodies dancing in a virtual paradise. We will share deep thoughts with other lines of computer code, living out this grand illusion. We have great, heroic exploits conquering new worlds, oblivious to the fact that we are just electrons dancing inside some computer. Until, of course, someone hits the off button.
    But one problem with pushing these scenarios too far is the Cave Man Principle. As we mentioned earlier, the architecture of our brains is that of a primitive hunter-gatherer who emerged from Africa more than 100,000 years ago. Our deepest desires, our appetites, our wants were all forged in the grasslands of Africa as we evaded predators, hunted for game, foraged in the forests, looked for mates, and entertained ourselves at the campfire.
    One of our prime directives, buried deep in the fabric of our thoughts, is to look good, especially to the opposite sex and our peers. An enormous fraction of our disposable income, after entertainment, is devoted to our appearance. That is why we have had the explosive growth in plastic surgery, Botox, grooming products, sophisticated clothing, as well as learning new dance steps, muscle building, buying the latest music, and keeping fit. If you add all this up, it becomes a huge portion of consumer spending, which in turn generates a large fraction of the U.S. economy.
    This means that, even with the ability to create perfect bodies that are nearly immortal, we will probably resist the desire for robotic bodies if we look like a clumsy robot with implants dangling out of our heads. No one wants to look like a refugee from a science fiction movie. If we have enhanced bodies, they must make us attractive to the opposite sex and enhance our reputation among our peers, or we will reject them. What teenager wants to be enhanced but look uncool?
    Some science fiction writers have relished the idea that we will all become detached from our bodies and exist as immortal beings of pure intelligence living inside some computer, contemplating deep thoughts. But who would want to live like that? Perhaps our descendants will not want to solve differential equations describing a black hole. In the future, people may want to spend more time listening to rock music the old-fashioned way than calculate the motions of subatomic particles while living inside a computer.
    Greg Stock of UCLA goes further and finds there are few advantages to having our brains hooked up to a supercomputer. He said, “ When I try to think of what I might gain by having a working link between my brain and a supercomputer, I am stymied if I insist on two criteria: that the benefits could not be as easily achieved through some other, noninvasive procedure, and that the benefits must be worth the discomforts of brain surgery.”
    So although there are many possible options for the future, I personally believe that the most likely path is that we will build robots to be benevolent and friendly, enhance our own abilities to a degree, but follow the Cave Man Principle. We will embrace the idea of temporarily living the life of a superrobot via surrogates but will be resistant to the idea of permanently living out our lives inside a computer or altering our body until it becomes unrecognizable.
    ROADBLOCKS TO THE SINGULARITY
    No one knows when robots may become as smart as humans. But personally, I would put the date close to the end of the century for several reasons.
    First, the dazzling advances in computer technology have been due to Moore’s law. These advances will begin to slow down and might even stop around 2020–25, so it is not clear if we can reliably calculate the speed of computers beyond that. (See Chapter 4 for more on the post-silicon era.) In this book, I have assumed that computer power will continue to grow, but at a slower rate.
    Second, even if a computer can calculate at fantastic speeds like 10 16 calculations per second, this does not necessarily mean that it is smarter than us. For example, Deep Blue, IBM’s chess-playing machine, could analyze 200 million positions per second, beating the world champion. But Deep Blue, for all its speed and raw computing power, cannot do anything else. True intelligence, we learned, is much more than calculating chess positions.
    For