Today, in the young field of nanotechnology, scientists and engineers are taking control of atoms and molecules individually, manipulating them and putting them to use with an extraordinary degree of precision. Word of the promise of nanotechnology is spreading rapidly, and the air is thick with news of nanotech breakthroughs. Governments and businesses are investing billions of dollars in nanotechnology R&D, and political alliances and battle lines are starting to form. Public awareness of nanotech is clearly on the rise, too, partly because references to it are becoming more common in popular culture-with mentions in movies, books, video games, and television.
Yet there remains a great deal of confusion about just what nanotechnology is, both among the ordinary people whose lives will be changed by the new science, and among the policymakers who wittingly or unwittingly will help steer its course. Much of the confusion comes from the name "nanotechnology," which is applied to two different things-that is, to two distinct but related fields of research, one with the potential to improve today's world, the other with the potential to utterly remake or even destroy it. The meaning that nanotechnology holds for our future depends on which definition of the word "nanotechnology" pans out.
From Feynman to Sunscreen
Although a few scientists had done related work earlier, nanotechnology didn't really get going until the second half of the twentieth century. Credit for inspiring nanotechnology usually goes to Richard Feynman, a brilliant Caltech physicist who later won a Nobel Prize for "fundamental work in quantum electrodynamics." In an after-dinner lecture ("There's Plenty of Room at the Bottom") delivered on the evening of December 29, 1959, Feynman proposed work in a field "in which little has been done, but in which an enormous amount can be done in principle."
"What I want to talk about," Feynman said, "is the problem of manipulating and controlling things on a small scale." Feynman described how the entire Encyclopaedia Britannica could be written on the head of a pin, and how all the world's books could fit in a pamphlet. Such remarkable reductions could be done as "a simple reproduction of the original pictures, engravings, and everything else on a small scale without loss of resolution." Yet it was possible to get smaller still: if you converted all the world's books into an efficient computer code instead of just reduced pictures, you could store "all the information that man has carefully accumulated in all the books in the world … in a cube of material one two-hundredth of an inch wide-which is the barest piece of dust that can be made out by the human eye. So there is plenty of room at the bottom!" He declared that "the principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom"-in fact, Feynman saw atomic manipulation as inevitable, "a development which I think cannot be avoided."
Research in the direction Feynman suggested didn't begin immediately, although the next few decades brought sophisticated new tools and techniques for manipulating matter at the atomic level. One early demonstration of this power came in 1990 when a team of IBM physicists revealed that they had, the year before, spelled out the letters "IBM" using 35 individual atoms of xenon. In 1991, the same research team built an "atomic switch," likely to be an important development in the future of computing.
Another breakthrough came with the discovery of new shapes for molecules of carbon, the quintessential element of life. In 1985, researchers reported the discovery of the "buckyball," a lovely round molecule consisting of 60 carbon atoms. This led in turn to the 1991 discovery of a related molecular shape known as the "carbon nanotube"; these nanotubes are about 100 times stronger than steel but just a sixth of the weight, and they have unusual heat and conductivity characteristics that guarantee they will be important to high technology in the coming years.
But these exciting discoveries are the exception rather than the rule: Most of what passes for nanotechnology nowadays is really just materials science. Such "mainstream nanotechnology," as practiced by hundreds of companies spending billions of dollars, is merely the intellectual offspring of conventional chemical engineering and our new nanoscale powers. It is already being incorporated in consumer products: some lines of sunscreens and cosmetics, some stain- and water-repellent clothing, some new paints, a few kinds of anti-reflective and anti-fogging glass, and some tennis equipment. In short, mainstream nanotechnology is an interesting field, with some impressive possibilities for improving our lives with better materials and tools. But that's just half the story: there's another side to nanotechnology, one that promises much more extreme, and perhaps dangerous, changes.
Molecular Manufacturing
This more radical form of nanotechnology originated in the mind of an M.I.T. undergraduate in the mid-1970s. Eric Drexler, who went on to obtain a Ph.D. from M.I.T., realized that the biological "machinery" already responsible for the full diversity of life on Earth could be adapted to build nonliving products upon command. Molecule-sized machines, modeled after those found in nature, could be used to manufacture just about anything man wished.
Drexler, who began to develop these theories even before he'd heard of Feynman's lecture, first published his ideas in a 1981 journal article. Five years later, he brought the notion of molecular manufacturing to the general public with his book Engines of Creation. An astonishingly original work of futurism, Engines of Creation pointed out how molecular manufacturing would revolutionize other areas of science and technology-leading to breakthroughs in medicine, artificial intelligence, and the conquest of space. Drexler refutes every technical objection he can anticipate, explaining how such phenomena as quantum uncertainty and thermal vibrations don't make molecular manufacturing impossible. It was also in Engines that Drexler introduced the term "nanotechnology"-a reference to the nanometer, one-billionth of a meter-to describe this approach to molecular manufacturing, although the term is now also used for the more mundane applications (cosmetics, tennis balls, etc.) described above.
To shore up his technical arguments for the feasibility of his vision, Drexler further expanded on his ideas in the world's first nanotechnology textbook. Nanosystems (1992), a dense volume that grew out of a class he taught at Stanford, is crammed with equations and diagrams and designs for molecular machines, and it has gone far to put the theory of molecular manufacturing on sound technical footing-although scientific debate about the achievability and the best routes to developing nanotechnology has continued.
In the past decade, theorists have begun to flesh out the details of how nanotechnology might be used in manufacturing and medicine, although it is unclear how soon any of this will be possible. Some analysts have estimated that major breakthroughs in molecular manufacturing are at least three decades away; others have suggested that major progress might occur in the next five years.
Controversy and Policy
Since 2000, awareness of nanotechnology among environmental activists, regulators, and lawmakers has been on the rise. Environmental organizations have expressed fears about the potential ecological and health consequences of mainstream nanotechnology, and have called for increased research into safety of nanoparticles.
The Drexler version of advanced nanotechnology has also been the subject of public fear, largely centered on the notion that nanotechnology could spiral out of control and convert all life on Earth into "gray goo." Drexler, who originally introduced this apocalyptic prospect in Engines of Creation, has since repeatedly distanced himself from it-but gray goo retains its grip on the public imagination.
There are other serious reasons to be worried about the development of nanotechnology, including the risk of severe economic disruption; the possibly dehumanizing effects of using nanotechnology on ourselves; and the potential criminal, military, or terrorist use of advanced nanotechnology. A few organizations are paying full-time attention to these concerns, including the Foresight Institute (established in 1986) and the Center for Responsible Nanotechnology (established in 2002).
Public policy discussions have barely begun to reflect those long-term concerns. Although some agencies in the U.S. government have been involved in nanotechnology since the 1980s, federal funding of nanotechnology research did not begin in earnest until the late 1990s. In 2000, the National Nanotechnology Initiative was established to coordinate the government's work in nanotechnology; soon, federal spending on nanotechnology is scheduled to cross the $1 billion-per-year mark. Along with the increased funding has come a government commitment to investigate the "social, economic, health, and environmental implications" of nanotechnology. As public interest continues to grow, and as scientific progress make advanced nanotechnology seem ever more attainable, policymakers are likely to increasingly turn their attentions to the promise and peril of nanotechnology.
