In this week's issue of the magazine, I wrote a story about some of the hype over nanotechnologyparticularly estimates of how big of a market various nanoproducts might someday have. But it's hard to talk about nanotech without mentioning the guy who invented the term: Eric Drexler, author of the 1986 book Engines of Creation. (Drexler and everyone else in the field credit the founding vision behind nanotech to a 1959 talk by Caltech physicist Richard Feynman). In researching my article, I had a fascinating E-mail chat with Drexler. Here is some of that exchange:
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Next News: As you know, the term "nanotechnology" gets thrown around a lot these days. Explain your vision of nanotech.
Drexler: My work has explored consequences of the Feynman vision of nanotechnology, based on nanomachines building with atom-by-atom control. Achieving this is a long-term engineering objective, not something that can be done in the laboratory today. Once developed, the resulting molecular manufacturing technology promises enormous potential upsides and downsides. If it is feasible, then molecular manufacturing is the natural long-term goal for nanotechnology. If it were impossible, it would be a distracting illusion.
Next News: What is the key feature of the Drexlerian vision of nanotechnology?
Drexler: A central point is the ability to make any of a wide range of complex products just by changing the programsort of like a computer-driven printer able to make any pattern of ink spots, but arranging atoms in 3-D. I emphasize "sort of like" here, because the atoms can only end up in places that make physical sense, that is, forming nice, stable materials and structures. Ink spots can be put anywhere. ... By the way, no one doing research in this area would call their work "Drexlerian"the basic idea originated with Feynman, and isn't generally labeled with a person's name.
Next News: The putting of atoms where you want them, or "positional control," seems to be one key area of criticism of your version of nanotech.
Drexler: [Don't confuse] "atom-by-atom control" with "picking up and placing single atoms." The former doesn't require the latter, which is hard to do. What I've described is atom-by-atom control by guiding chemical reactions with atom-scale positional accuracy. What some would-be critics have attacked is the straw-man idea of picking and placing single atoms using tiny fingers. Be warned! Confronted with the actual concept, these critics have fallen silent, because the actual concept is so obviously workable.
Next News: Many in the field, particularly in the business community, think your vision is a distracting fantasy from the near-term, commercial work they are doing.
Drexler: The nanobusiness community has gotten misleading advice on the long-term feasibility of molecular manufacturing from laboratory scientists. ... It is only natural that many laboratory researchers seem skeptical. Molecular manufacturing is a long-term engineering goal that is beyond the horizon of their scientific work and budget cycles. Few have studied the scientific literature on the subject (many seemingly don't know that one exists). The whole subject obviously makes them uncomfortable. Further, one of their leadersa Nobel laureatehad offered misleading assurances that the basic goal ... of atom-by-atom control ... is physically impossible. Given his stature, this has had a chilling effect on the field.
Next News: What, exactly, could molecular manufacturing do?
Drexler: It could produce desktop nanofactories able to convert cheap liquid feedstocks into high-tech products within minutesproducts such as laptop computers with a billion times more processing power than modern machines, or sheets of tough, flexible solar-cell material suitable for reroofing a house or repaving a driveway, or 3-D video wallpaper, or parts that snap together to make a new nanofactory. It's important to make clear that such results will be possible only after completing a major systems-engineering projecta project that most science-oriented "nanotechnologists" aren't now contemplating, even though they are laying the groundwork for undertaking it.
Next News: What do you mean by "cheap, liquid feedstocks"?
Drexler: The feedstock material needs to contain the atoms needed for the products, in the form of simple molecules. If the products will be mostly made of carbon (like plastics, nanotubes, and diamond), the liquid can be mostly a hydrocarbon, like mineral oil. Supplying other kinds of atoms requires mixing in other ingredients, mostly of the sort you can find in cans at a hardware store.
Next News: But you're not describing some sort of "anything box," are you?
Drexler: To be able to make "absolutely anything that could exist" would require making not just complex, useful objects, designed for easy fabrication and made of strong, stable engineering materials, but bizarre objects containing interlocking highly-stressed parts made of sensitive, explosive materials, or anything else that someone might invent for the specific purpose of being impossible to build. The effort we've spent on this point shows that talk of "universal assemblers" is an effective way to distract people from practical issues. A straw man and a red herring, all rolled up in one!
Next News: The government's National Nanotechnology Initiative isn't focusing on your sort of nanotech. If the government had a separate, $10 billion-a-year program devoted to your version of nanotech, when might we see nanofactories?
Drexler: I've described advanced systems, and I think some people have become confused, thinking that those would somehow have to be the first step. I think that most people who've looked at the problem in any detail would agree that a simple molecular assembler system, guiding chemical reactions in a liquid medium, could be built in less than 10 years with a small fraction of that investment. Researchers are already building structures with atom-by-atom positional control, while others are building simple molecular machines.