A publication of the Foresight Institute
FI: What led to your work on nanotechnology?
Drexler: For many years I'd been concerned about technology and the future, and had been looking at what could be built with tools that we didn't have yet. My work at MIT had focused on what we could build in space once we had inexpensive space transportation and industrial facilities in orbit. And this led to various sorts of work in space development.
But while doing that I'd been following a variety of fields in science and technology, including the work in molecular biology, genetic engineering, and so forth. I had been impressed by the fact that biological systems were based on molecular machines and that we were learning to design and build these sorts of things. This got me thinking about what sorts of things we could build when we got good at designing molecules. And this led pretty rapidly to the idea of self-assembling systems of molecules that could act as molecular machines--and the idea of molecular machines that could build other molecular machines. This was in the spring of 1977.
FI: This was the assembler idea?
Drexler: The assembler, yes, but the name came later. After realizing that we would eventually be able to build molecular machines that could arrange atoms to form virtually any pattern that we wanted, I saw that an awful lot of consequences followed from that. It began to look like one of the most important developments that we'd face in our future. And concern with this began to absorb more and more of my time.
|It began to look like one of the most important developments that we'd face in our future.|
FI: How do you think we're going to get to
Drexler: Well, it's hard to say. It's a lot easier to see, at least in some cases, what the long-term limits of the possible will be, because they depend on natural law. But it's much harder to see just what path we will follow in heading toward those limits. It's like the difference between seeing mountains in the distance and knowing that there must be some way of reaching them and trying to figure out just what the easiest path to follow will be, as you cross a jumbled landscape of rivers and cliffs and underbrush between here and there.
At present, some areas of research that are leading in the direction of nanotechnology include protein engineering, other sorts of biochemical engineering, the beginnings of a micromanipulator technology growing out of the technology of the scanning tunneling microscope, and also more conventional sorts of chemistry. Which of these will in fact play the greater role is hard to say, and it may well be that all of them will play a role in the path that's eventually followed.
FI: Why do you emphasize the protein engineering path in your book and talks, rather than these other paths?
Drexler: Well, there are several reasons. In thinking about nanotechnology today, what's most important is understanding where it leads, what nanotechnology will look like after we reach the assembler breakthrough. But how we get to nanotechnology--what the intermediate technologies are, the enabling technologies--will make essentially no difference in what nanotechnology itself is like.
An analogy I like to use is that the shape of the wings and the composition of the aluminum in a 747 jet doesn't depend on the shape of the wings and the kind of cloth that was used in the Wright Flyer. The Wright brothers set us on the path to modern aircraft, but what we build today depends on technology today--our design abilities, the quality of our tools, and the materials we have to work with. Likewise nanotechnology will, once it gets under way, depend on the tools we have then and our ability to use them, and not on the steps that got us there.
So what's important right now is to understand that there are steps that lead to this new place. Protein engineering is not only a promising path, but it provides a very compact and (I think) persuasive argument for being able to build molecular machines, because proteins are molecular machines. We already see them serving the range of functions that are needed. That's not true for conventional chemistry or scanning tunneling microscope technology. They're not starting out as a technology of molecular machines, so they don't make such a neat case for nanotechnology.
FI: Aren't there also advantages in using that analogy because protein engineering is a form of biotechnology--something that people know should go ahead, but that they know has some risk? Is that another reason to emphasize this path, because it gets people thinking along the right lines?
Drexler: Yes, I think that makes sense. And again what that points to is the greater similarity between protein systems and real nanotechnology than between other enabling technologies and nanotechnology. Protein engineering is a technology of molecular machines--of molecular machines that are part of replicators--and so it comes from an area that already raises some of the issues that nanotechnology will raise.
FI: What do you think of the rate of progress toward nanotechnology?
Drexler: I'm impressed by the rate of progress. It's as fast or even a little faster than I had been expecting when I first published a paper on assemblers back in 1981. How fast it will move in the future is very hard to say, but we're clearly on the path to nanotechnology, indeed on several different paths to nanotechnology. An international race in the relevant technologies is getting under way at this point, not necessarily with an understanding of where that race leads in the long run, but strongly motivated by the short-term payoffs.
Concluded next issue
NASA's "accelerated: scenario:
Return to lunar surface 2010 Flight to Jupiter 2100 Flight to Saturn 2120
Two possible drawbacks to space technologies are additions to the burden of government spending and pollution from rocket exhaust. The American Rocket Company of Camarillo, CA, is tackling both. As a privately funded company, AMROC has developed its engines without federal investment. Further, their hybrid rocket engines--using solid fuel and liquid oxidizer--are environmentally cleaner than the Space Shuttle (important when launch rates become high). Hybrids are also incapable of a Shuttle-style explosion. AMROC is now testing full-scale engines at Edwards Air Force base.
The ALCOR Life Extension
Foundation officially opened its new research and patient
care facility in Riverside, California over Memorial Day weekend.
Its 5000 square feet include an operating room, laboratory area,
staff sleeping quarters, X-ray room, conference room, loft
storage area, and patient care facilities. All elements of the
facility, from the walls to the roof to glassware storage
shelves, were designed to survive a massive earthquake.
The building was open for public inspection on May 24. Also on view was ALCOR's modular ambulance outfitted with the newly deployed Mobile Advanced Life Support Unit. For more information, call 714-736-1703
See their Web site for current information on Alcor.
If you find information and clippings of relevance to FI's goal of preparing for future technologies, please forward them to us for possible coverage in FI Update. Letters and opinion pieces will also be considered; submissions become the property of the Foresight Institute and may be edited. Write to the Foresight Institute, Box 61058, Palo Alto, CA 94306
"Molecular Engineering: Assemblers and Future
Space Hardware," K. Eric Drexler. Paper AAS-86-415,
presented at Aerospace XXI, the 33rd annual meeting of the
American Astronautical Society, Boulder, Colorado, 26-29 October
Provides a general overview of molecular machines and assemblers from a mechanical engineering viewpoint, briefly sketching applications to space systems.
Molecular structures of probe and gate knobs with attached carbyne rods, for use in the transistor-like "locks of mechanical nanocomputers. From illustrations in "Rod Logic and Thermal Noise in the Mechanical Nanocomputer"
"Rod Logic and Thermal Noise in the Mechanical Nanocomputer," K. Eric Drexler. Proceedings of the Third International Symposium on Molecular Electronic Devices, Forrest Carter (ed.), Elsevier North Holland, in press.
Sketches various approaches to nanotechnology (protein engineering, synthetic chemistry, micromanipulators), then focuses on the fundamental elements of mechanical nanocomputers: wire-like signal transmission rods and transistor-like mechanical locks. Describes the structure and mechanical properties of these moving parts and derives estimates for friction and energy loss resulting from rod motions. Finally models and analyzes the effects of thermal noise, leading to the description of a rod design which yields an overall error rate of less than one in a trillion logic operations.
Logic speeds are consistent with a gigahertz system clock; devices sizes are consistent with volumes on the order of a thousandth of a cubic micron per CPU.
For an extended discussion of the topic of the above paper, see chapter 12 of Nanosystems.
David Forrest of the MIT NSG has prepared an information packet, entitled "Nanotechnology Press Kit," which we understand is available to anyone on request from the MIT News Office, 77 Massachusetts Ave., Cambridge, MA 02139. It includes four short essays and a list of audio cassettes available on the topic.
Proceedings of the Third International Symposium
on Molecular Electronic Devices,
Forrest Carter (ed.), Elsevier North Holland, in press. A
collection of technical papers on molecular electronics and
subjects more-or-less related to it. Few relate directly to the
construction of molecular circuits or computers.
The Blind Watchmaker, Richard Dawkins, Norton, 1986. A lively and readable account of biological evolution--of the amazing complexity of living things and of how this complexity can be explained. Covers modern debates on evolution from the perspective of a prominent participant.
Engines of Creation, K. Eric Drexler, Anchor Press/Doubleday, 1986. Describes what nanotechnology is and what it will mean to medicine, economics, the arms race, and much else. The book that introduced the subject.
Getting to Yes, Roger Fisher and William Ury, Houghton Mifflin, 1981. Suggests ways to improve negotiations, making them faster, fairer, more productive, and less disruptive, by focusing on principles rather than positions. Good memes to share among people working together to get things done.
The Tomorrow Makers, Grant Fjermedal, Macmillan, 1986. An account of the frontiers of robotics, artificial intelligence, and nanotechnology told through interviews with leaders in these fields. Focuses on the wild human possibilities of the coming revolutions in technology.
The Society of Mind, Marvin Minsky, Simon and Schuster, 1986. An interwoven collection of ideas on thinking. Describes the mind as an intelligent system made up of less intelligent parts, themselves made of still simpler parts. Deals with a higher level of organization than simple neural networks.
Parallel Distributed Processing, Volume One, David Rumelhart, James McClelland, et al., MIT Press, 1986. A good, technical introduction to recent work in neural-style computation. Describes general features of these models, specific approaches, and the results of a range of experiments on learning in neural networks.
From Foresight Update 1, originally published 15 June 1987.