Physics of the Future by Michio Kaku

  So, given the chance, people will often misuse technology and create an enormous amount of mischief. What happens if they get hold of genetic engineering?

  In a worst-case scenario, we might have the nightmare imagined by H. G. Wells in his classic science fiction novella The Time Machine, when the human race, in the year 802,701 AD, splits into two distinct races. He wrote, “Gradually, the truth dawned on me: that Man had not remained one species, but had differentiated into two distinct animals: that my graceful children of the Upper World were not the sole descendants of our generation, but that this bleached, obscene, nocturnal Thing, which had flashed before me, was also heir to all the ages.”

  To see what variations of the human race are possible, simply look at the household dog. Although there are thousands of breeds of dogs, all originally descended from Canis lupus, the gray wolf, which was domesticated roughly 10,000 years ago at the end of the last Ice Age. Because of selective breeding by their human masters, dogs today come in a bewildering variety of sizes and shapes. Body shape, temperament, color, and abilities have all been radically altered by selective breeding.

  Since dogs age roughly seven times faster than humans, we can estimate that about 1,000 generations of dogs have existed since they separated from wolves. If we apply this to humans, then systematic breeding of humans might split the human race into thousands of breeds in only 70,000 years, although they would be of the same species. With genetic engineering, this process could conceivably be vastly accelerated, to a single generation.

  Fortunately, there are reasons to believe the speciation of the human race will not happen, at least not in the coming century. In evolution, a single species usually splits apart if it separates geographically into two separate breeding populations. This happened, for example, in Australia, where the physical separation of many animal species has led to the evolution of animals found nowhere else on earth, such as marsupials like the kangaroo. Human populations, by contrast, are highly mobile, without evolutionary bottlenecks, and are highly intermingled.

  As Gregory Stock of UCLA has said, “Traditional Darwinian evolution now produces almost no change in humans and has little prospect of doing so in the foreseeable future. The human population is too large and entangled, and selective pressures are too localized and transitory.”

  There are also constraints coming from the Cave Man Principle.

  As we mentioned earlier, people often reject the advances of technology (for example, the paperless office) when it contradicts human nature, which has remained relatively constant over the past 100,000 years. People may not want to create designer children who deviate from the norm and are considered freaks by their peers. This decreases their chances of success in society. Dressing one’s children in silly clothing is one thing, but permanently changing their heredity is an entirely different thing. (In a free market, there probably will be a place for weird genes, but it will be small, since the market will be driven by consumer demand.) More than likely, by the end of the century, a couple will be given a library of genes to choose from, mostly those for eliminating genetic diseases but also some for genetic enhancement. However, there will be little market pressure to finance the study of bizarre genes because the demand for them will be so small.

  The real danger will come not so much from consumer demand but from dictatorial governments that may want to use genetic engineering for their own purposes, such as breeding stronger but more obedient soldiers.

  Another problem arises in the distant future, when we have space colonies on other planets whose gravity and climactic conditions are much different from the earth. At that point, perhaps in the next century, it becomes realistic to think of engineering a new breed of humans who can adjust to different gravity fields and atmospheric conditions. For example, a new breed of humans may be able to consume different amounts of oxygen, adjust to a different length of day, and have a different body weight and metabolism. But space travel will be expensive for a long time. By the end of the century, we may have a small outpost on Mars, but an overwhelming fraction of the human race will still be on the earth. For decades to centuries to come, space travel will be for astronauts, the wealthy, and maybe a handful of hardy space colonists.

  So the splitting of the human race into different spacefaring species around the solar system and beyond will not happen in this century, or perhaps even the next. For the foreseeable future, unless there are dramatic breakthroughs in space technology, we are largely stuck on the earth.

  Lastly, there is yet another threat that faces us before we reach 2100: that this technology may be deliberately turned against us, in the form of designer germ warfare.

  GERM WARFARE

  Germ warfare is as old as the Bible. Ancient warriors used to hurl diseased bodies over the walls of enemy cities or poison their wells with the bodies of diseased animals. Deliberately giving smallpox-infected clothing to an adversary is another way to destroy them. But with modern technology, germs can be genetically bred to wipe out millions of people.

  In 1972, the United States and the former Soviet Union signed an historic treaty banning the use of germ warfare for offensive purposes. However, the technology of bioengineering is so advanced today that the treaty is meaningless.

  First, there is no such thing as offensive and defensive technology when it comes to DNA research. The manipulation of genes can be used for either purpose.

  Second, with genetic engineering, it is possible to create weaponized germs, those that have been deliberately modified to increase their lethality or their ability to spread into the environment. It was once believed that only the United States and Russia possessed the last vials containing smallpox, the greatest killer in the history of the human race. In 1992, a Soviet defector claimed that the Russians had weaponized smallpox and actually produced up to twenty tons of it. With the breakup of the Soviet Union, there is the nagging fear that one day a terrorist group may pay to gain access to weaponized smallpox.

  In 2005, biologists successfully resurrected the Spanish flu virus of 1918, which killed more people than World War I. Remarkably, they were able to resurrect the virus by analyzing a woman who had died and was buried in the permafrost of Alaska, as well as samples taken from U.S. soldiers during the epidemic.

  The scientists then proceeded to publish the entire genome of the virus on the Web, making it known to the entire world. Many scientists felt uneasy about this, since one day even a college student with access to a university laboratory might be able to resurrect one of the greatest killers in the history of the human race.

  In the short term, the publication of the genome of the Spanish flu virus was a bonanza for scientists, who then could examine the genes to solve a long-standing puzzle: How did a tiny mutation cause such widespread damage to the human population? The answer was soon found. The Spanish flu virus, unlike other varieties, causes the body’s immune system to overreact, releasing large amounts of fluid that eventually kills the patient. The person literally drowns in his own fluids. Once this was understood, the genes that cause this deadly effect could be compared to the genes of the H1N1 flu and other viruses. Fortunately, none of them possessed this lethal gene. Moreover, one could actually calculate how close a virus was to attaining this alarming capability, and the H1N1 flu was still far from achieving this ability.

  But in the long term, there is a price to pay. Every year, it becomes easier and easier to manipulate the genes of living organisms. Costs keep plummeting, and the information is widely available on the Internet.

  Within a few decades, some scientists believe that it will be possible to create a machine that will allow you to create any gene simply by typing the desired components. By typing in the A-T-C-G symbols making up a gene, the machine will then automatically splice and dice DNA to create that gene. If so, then it means that perhaps even high school students may one day do advanced manipulations of life-forms.

  One nightmare scenario is airborne AIDS. Cold viruses,
for example, possess a few genes that allow them to survive in droplets of aerosols, so that sneezing can infect others. At present, the AIDS virus is quite vulnerable when it is exposed to the environment. But if the cold virus genes are implanted into the AIDS virus, then it is conceivable that they might make it able to survive outside the human body. This could then cause the AIDS virus to spread like the common cold, thereby infecting a large portion of the human race. It is also known that viruses and bacteria do exchange genes, so there is also the possibility that the AIDS and common cold viruses can exchange genes naturally, although this is less likely.

  In the future, a terrorist group or nation-state may be able to weaponize AIDS. The only thing preventing them from unleashing it would be the fact that they, too, would also perish if the virus were to be dispersed into the environment.

  This threat became real right after the tragedy of 9/11. An unknown person mailed packets of a white powder containing anthrax spores to well-known politicians around the country. A careful, microscopic analysis of the white powder showed that the anthrax spores had been weaponized for maximum death and destruction. Suddenly, the entire country was gripped with fear that a terrorist group had access to advanced biological weapons. Although anthrax is found in the soil and throughout our environment, only a person with advanced training and maniacal intentions could have purified and weaponized the anthrax and pulled off this feat.

  Even after one of the largest manhunts in U.S. history, the culprit was never found, even to this day (although a leading suspect recently committed suicide). The point here is that even a single individual with some advanced biological training can terrorize an entire nation.

  One restraining factor that has kept germ warfare in check is simple self-interest. During World War I, the efficacy of poison gas on the battlefield was mixed. The wind conditions were often unpredictable, so the gas could blow back onto your own troops. Its military value was largely in terrorizing the enemy, rather than defeating him. Not a single decisive battle was won using poison gas. And even at the height of the Cold War, both sides knew that poison gas and biological weapons could have unpredictable effects on the battlefield, and could easily escalate to a nuclear confrontation.

  All the arguments mentioned in this chapter, as we have seen, involved the manipulation of genes, proteins, and molecules. Then the next question naturally arises: How far can we manipulate individual atoms?

  The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom.

  —RICHARD FEYNMAN, NOBEL LAUREATE

  Nanotechnology has given us the tools to play with the ultimate toy box of nature—atoms and molecules. Everything is made from these, and the possibilities to create new things appear limitless.

  —HORST STORMER, NOBEL LAUREATE

  The role of the infinitely small is infinitely large.

  —LOUIS PASTEUR

  The mastery of tools is a crowning achievement that distinguishes humanity from the animals. According to Greek and Roman mythology, this process began when Prometheus, taking pity on the plight of humans, stole the precious gift of fire from Vulcan’s furnace. But this act of thievery enraged the gods. To punish humanity, Zeus devised a clever trick. He asked Vulcan to forge a box and a beautiful woman out of metal. Vulcan created this statue, called Pandora, and then magically brought her to life, and told her never to open the box. Out of curiosity, one day she did, and unleashed all the winds of chaos, misery, and suffering in the world, leaving only hope in the box.

  So from Vulcan’s divine furnace emerged both the dreams and the suffering of the human race. Today, we are designing revolutionary new machines that are the ultimate tools, forged from individual atoms. But will they unleash the fire of enlightenment and knowledge or the winds of chaos?

  Throughout human history, the mastery of tools has determined our fate. When the bow and arrow were perfected thousands of years ago, it meant that we could fire projectiles much farther than our hands could throw them, increasing the efficiency of our hunting and increasing our food supply. When metallurgy was invented around 7,000 years ago, it meant that we could replace huts of mud and straw and eventually create great buildings that soared above the earth. Soon, empires began to rise from the forest and the desert, built by the tools forged from metals.

  And now we are on the brink of mastering yet another type of tool, much more powerful than anything we have seen before. This time, we will be able to master the atoms themselves out of which everything is created. Within this century, we may possess the most important tool ever imagined—nanotechnology that will allow us to manipulate individual atoms. This could begin a second industrial revolution, as molecular manufacturing creates new materials we can only dream about today, which are superstrong, superlight, with amazing electrical and magnetic properties.

  Nobel laureate Richard Smalley has said, “The grandest dream of nanotechnology is to be able to construct with the atom as the building block.” Philip Kuekes of Hewlett-Packard said, “Eventually, the goal is not just to make computers the size of dust particles. The idea would be to make simple computers the size of bacteria. Then you could get something as powerful as what’s now on your desktop into a dust particle.”

  This is not just the hope of starry-eyed visionaries. The U.S. government takes it seriously. In 2009, because of nanotechnology’s immense potential for medical, industrial, aeronautical, and commercial applications, the National Nanotechnology Initiative allocated $1.5 billion for research. The government’s National Science Foundation Nanotechnology Report states, “Nanotechnology has the potential to enhance human performance, to bring sustainable development for materials, water, energy, and foods, to protect against unknown bacteria and viruses ….”

  Ultimately, the world economy and fate of nations may depend on this. Around 2020 or soon afterward, Moore’s law will begin to falter and perhaps eventually collapse. The world economy could be thrown into disarray unless physicists can find a suitable replacement for silicon transistors to power our computers. The solution to the problem may come from nanotechnology.

  Nanotechnology might also, perhaps by the end of this century, create a machine that only the gods can wield, a machine that can create anything out of almost nothing.

  THE QUANTUM WORLD

  The first to call attention to this new realm of physics was Nobel laureate Richard Feynman, who asked a deceptively simple question: How small can you make a machine? This was not an academic question. Computers were gradually becoming smaller, changing the face of industry, so it was becoming apparent that the answer to this question could have an enormous impact on society and the economy.

  In his prophetic talk given in 1959 to the American Physical Society titled “There’s Plenty of Room at the Bottom,” Feynman said, “It is interesting that it would be, in principle, possible (I think) for a physicist to synthesize any chemical substance that the chemist writes down. Give the orders and the physicist synthesizes it. How? Put the atoms down where the chemist says, and so you make the substance.” Feynman concluded that machines made out of individual atoms were possible, but that new laws of physics would make them difficult, but not impossible, to create.

  So ultimately, the world economy and the fate of nations may depend on the bizarre and counterintuitive principles of the quantum theory. Normally, we think that the laws of physics remain the same if you go down to smaller scales. But this is not true. In movies like Disney’s Honey, I Shrunk the Kids and The Incredible Shrinking Man, we get the mistaken impression that miniature people would experience the laws of physics the same way we do. For example, in one scene in the Disney movie, our shrunken heroes ride on an ant during a rainstorm. Raindrops fall onto the ground and make tiny puddles, just as in our world. But in reality, raindrops can be larger than ants. So when an ant encounters a raindrop, it would see a huge hemisphere of water. The hemisphere of water does not collapse because surface tension acts
like a net that holds the droplet together. In our world, surface tension of water is quite small, so we don’t notice it. But on the scale of an ant, surface tension is proportionately huge, so rain beads up into droplets.

  (Furthermore, if you tried to scale up the ant so that it was the size of a house, you have another problem: its legs would break. As you increase the size of the ant, its weight grows much faster than the strength of its legs. If you increase the size of an ant by a factor of 10, its volume and hence its weight is 10 × 10 × 10 = 1,000 times heavier. But its strength is related to the thickness of its muscles, which is only 10 × 10 = 100 times stronger. Hence, the giant ant is 10 times weaker, relatively speaking, than an ordinary ant. This also means that King Kong, instead of terrorizing New York City, would crumble if he tried to climb the Empire State Building.)

  Feynman noted that other forces also dominate at the atomic scale, such as hydrogen bonding and the van der Waals force, caused by tiny electrical forces that exist between atoms and molecules. Many of the physical properties of substances are determined by these forces.

  (To visualize this, consider the simple problem of why the Northeast has so many potholes in its highways. Every winter, water seeps into tiny cracks in the asphalt; the water expands as it freezes, causing the asphalt to crumble and gouging out a pothole. But it violates common sense to think that water expands when it freezes. Water does expand because of hydrogen bonding. The water molecule is shaped like a V, with the oxygen atom at the base. The water molecule has a slight negative charge at the bottom and a positive charge at the top. Hence, when you freeze water and stack water molecules, they expand, forming a regular lattice of ice with plenty of spaces between the molecules. The water molecules are arranged like hexagons. So water expands as it freezes since there is more space between the atoms in a hexagon. This is also the reason snowflakes have six sides, and explains why ice floats on water, when by rights it should sink.)