Alternate View Column AV-35
Keywords: nanotechnology, hypertext, DNA, molecular biology, rod logic
Published in the October-1989 issue of Analog Science Fiction & Fact Magazine;
This column was written and submitted 3/22/89 and is copyrighted © 1989, John G. Cramer. All rights reserved.
No part may be reproduced in any form without the explicit permission of the author.
Nanocon 1: The First Northwest Conference on Nanotechnology was held at the University Plaza Hotel in Seattle, Washington, on February 17-19, 1989. The conference was sponsored by the Seattle Nanotechnology Study Group and the University of Washington Student Nanotechnology Study Group. This AV column is a report on the conference.
Those of you who read the article "Nanotechnology" by Chris Peterson and K. Eric Drexler that was published in the Dec-87 Analog will be familiar with the term nanotechnology. It was coined by Drexler in his book Engines of Creation (EOC) and refers to the nanometer, a distance of 10-9 meters or roughly the diameter of an atom. Nanotechnology is the technical capability, not yet fully realized, which will make possible the structuring of matter with precise control at the nanometer scale, atom-by-atom or molecule-by-molecule, to form a specified pattern. Nanotechnology is the general ability to build large or small structures to complex atomic specifications. Notice that nanotechnology refers to the technique and ability, not the size or scale of the product. Nanotechnologic constructions may not necessarily be small.
Nanotechnology differs in important ways from the microtechnology (10-6 meter scale) presently used by the electronics industry to produce integrated circuit chips. The tools that assemble nanomachines can themselves be tiny assemblies of atoms. If even one general-purpose assembly nanomachine or assembler is available, it can be used to rapidly construct more identical assemblers in a geometric progression. It can rapidly mobilize as many assemblers as are needed to construct even very large structures from the available materials. Nanotechnology in effect can reduce all construction and manufacturing to a matter of software, of designing the command set that will specify the desired atomic structure and the steps required for its fabrication and assembly.
But the most striking aspect of nanotechnology lies in its biological implications. The cells of our bodies are, in essence, nanostructures. They even contain a specialized form of assembler, a nanomachine called a ribosome, which can and does assemble any protein from the command-steps encoded in linear RNA molecules. One implication of nanotechnology is that the biological functions of human cells can be directly controlled, repaired, and in some cases improved. Complex nanomachines that fit easily within our cells can take over their management and repair. The coming mastery of nanotechnology offers the promise of cures for cancer, hemophilia, diabetes, and other genetic disorders, the promise of the absolute elimination of all the parasitic, bacterial, and virus diseases that afflict humanity, the promise of the reversal of aging and extension of the human life span, the promise of the enhancement of human strength, endurance, sensory sensitivity, and even intelligence. And it also poses awesome threats and dangers arising from the many possible misuses of these new capabilities.
As a technological revolution, nanotechnology is perhaps unique in human history in one important way. Its arrival, its impact, and its problems have been thoroughly anticipated, largely through the work of Drexler, well before the actual technology is at hand. This did not happen with the industrial revolution, the nuclear age, the space age, or the computer revolution. A foreseen major revolution is unprecedented. There are several evident technological paths that will lead to nanotechnology, but it will be many years, perhaps many decades, before the full impact of these promises and problems will be upon us. We have time to consider, to steer development, to devise solutions to the problems. That is the point of this conference.
The Nanotechnology Conference opened with a banquet featuring a keynote address by Drexler. He described the state of nanotechnology as a developing field of inquiry and research, with emphasis on new developments, directions, and challenges. He pointed out that in 1988 a significant milestone predicted in EOC was achieved: the first useful protein with no equivalent in nature had been successfully synthesized in the laboratory. The age of engineered protein construction has arrived.
The conference participants were an interesting mix of academics, students, scientists, engineers, biologists, programmers, space advocates, and writers of both fiction and non-fiction. Some of the most original views expressed the conference came from the attending science fiction writers. Perhaps this should not come as a surprise, for SF writers as a group have devoted much time to studying the implications of possible future technologies. Greg Bear, Gregory Benford, Vonda McIntyre, Mark Stiegler, and I participated in the programming, and other SF writers in attendance contributed to the lively and far ranging discussions.
The Saturday program began with a talk by Eric Drexler on rod-logic computation. The capabilities of nano-scale computers that use electric currents are difficult to assess, because their properties are not well specified and their operation will necessarily lie in the domain where quantum mechanical interference phenomena are important, even dominant. Therefore, as a way of getting some realistic estimate of how much computing capability might be packed into a nano-scale computing device, Drexler has gone all the way back to the 19th century and the rod-and-cam computing devices designed by Charles Babbage, substituting stiff carbyne carbon-chain rods for Babbage's brass shafts and molecule lumps for Babbage's machined brass cams. A computer constructed in this way is in-principle possible and might even be mechanically robust. It offers the advantage that it can be readily analyzed for speed, capacity, power consumption, etc. It turns out that nanoscale rod-and-cam technology could be used to make a remarkably powerful computer. Drexler demonstrates that it is feasible, in the sense of not violating any physical laws, for a Cray-II class computer of this construction to be fitted into a small fraction of the volume of a cell, with plenty of space left over for nano-manipulators controlled by the nanocomputer and its software.
Profs. Nadrian Seeman of the New York University and Bruce Robinson of the University of Washington described their work on nucleic acid structural engineering which, as a currently available nanotechnology, represented a technical high point of the conference. They discussed the construction of rigid mechanical nanoscale structures that are made from DNA chains. Readers will recall that in cells DNA is not a structural material but a sort of reference library of protein designs, from which RNA transcriptions are made and sent to ribosomes for protein production.
But Seeman and Robinson explained that as structural material DNA offers several very interesting advantages: the chains are relatively rigid, can be made in the laboratory to designer specifications using solid-phase synthesis techniques, and will link, lock-and-key fashion, only to complementary sequence of bases of another DNA chain. They have produced several carefully designed DNA sequences that link to form three- and four-way junctions with "sticky" ends. These then become the units of a sort of "tinkertoy" construction set, from which complex two and three dimensional structures can be assembled with DNA rods and junctions. The uses for such DNA scaffolding in nanotechnology is not yet clear, but one possible application, as Robinson pointed out, might be for the conductors and switching junctions of current-mode nanoscale computers and memory devices. Another use might be to provide a relatively rigid and predictable framework upon which a true nanomachine might be fabricated.
The Saturday afternoon discussion focused on hypertext publishing. Hypertext (See Marc Stiegler's article in the Jan-89 Analog) is the ultimate generalization of the printed reference book, a large computer network with very large information storage and correlation capacity used for information searching, cross-referencing, discussion, criticism, and publication of new results. This concept is not nanotechnology, but in EOC Drexler suggested that hypertext publishing might uniquely keep pace with the rapid technological progress of nanotechnology and address the problems inherent in it. Speakers, including Drexler, Mark Stiegler of the Xanadu Corporation and L. Roberts of the Boeing Company, discussed the general concept of hypertext and its recent commercial implementations. These new systems, particularly the one being developed by Xanadu, may soon provide a reasonable approximation to the hypertext system envisioned by Drexler in EOC.
Sunday morning was devoted to a panel discussion on the social issues of nanotechnology. The discussion was very broad in its scope. Gregory Benford made a particularly interesting point during this panel. He suggested that some "precursor" social effects of nanotechnology are already here and should soon become more evident and important. When a large fraction of the population believes that nanotechnology is coming and will soon be a technological reality, they will, even before the technology is available, begin to act on the assumption that it will be developed. This will have social consequences.
Benford illustrated his point with the cryonics movement, the several
organizations that on the death of a subscribing member undertake to
cryogenically preserve his or her head or entire body, making it possible for
some future technologically advanced society to make the necessary repairs and
restore the "sleeper" to life. A few years ago this kind of resurrection
seemed to be a very remote possibility. But with the advent of nanotechnology
it seems much less a long shot. Benford predicted that with rising public
awareness of progress toward true nanotechnology there will be a large growth
in the cryonics movement. (Benford, incidentally, is now planning an SF novel
dealing with this subject.)
[Followup note: that novel, entitled Chillers (Bantam, 1994) is now in print. Benford used the author pseudonym "Stirling Blake".]
In the discussions of social issues during the panel, a certain pattern
emerged. The discussion would tightly focus on a particular impact or line of
development (the impact of human life extension on present retirement programs,
for example) while implicitly assuming that the rest of the social universe was
somehow frozen, unchanging. Drexler made an important point, cautioning that
the approach of changing one thing while holding everything else unmodified, as
is often done by engineers in analyzing complex electrical or mechanical
systems, can lead to seriously wrong social conclusions. He pointed out that
in a real society a large number of things will be changing at the same time.
Predictions which ignore societal changes on a broad front may be unduly
alarming (e.g., predicting bankruptcy of retirement pools) and probably
incorrect. More realistic assessment of the social problems arising from
change require a broader approach, where many social factors must evolve and
adjust together. Someone commented here that what we really need for analyzing
the impact of nanotechnology is Asimov's psychohistory.
The Sunday afternoon panel discussion, which I moderated, was an interactive workshop on paths to nanotechnology. We started by describing the various technological paths which lead from where we are to the realization of nanotechnology, and the ways in which each of these paths is presently blocked. The focus of the discussion shifted to the biological path, using the protein-producing machinery in cells to produce new nanomachine designs that can lead to a generalized assembler. This line of development is presently blocked by our inability to fully understand the operation of the ribosome or to predict how a protein with a particular sequence of amino acids will fold itself as it is created and becomes biologically active.
Prediction of protein folding is presently blocked by the difficulty of the computations. This led to discussion of the state of supercomputers and of radical new computer architectures such as neural-network circuits, and how these might lead to solution of the folding problem. The intrinsic instability of neural nets was mentioned. There was also discussion of the general problem of biological complexity: are we humans are really smart enough to master all the complexities of natural biological organisms, their structure, and their operation?
Those at the conference were optimistic, for there is presently steady progress
toward resolving theses complexities. Many of the conference attendees and
many more workers not attending the conference will continue to bang away at
the countless stumbling blocks between us and true nanotechnology. In the
years and decades that will be needed to go from here to there, those of us who
write hard science fiction will try to anticipate some of the triumphs and some
of the problems that will inevitably arise as this newest of technologies moves
from the sidelines to the center of the stage that is the world.
Proceedings are available by sending a check for $15 to Nanocon 1 Proceedings, P. O. Box 40176, Bellevue, WA 98004
K. Eric Drexler, Engines of Creation, Anchor Press/Doubleday, New York, (1987);
Chris Peterson and K. Eric Drexler, "Nanotechnology", Analog, Jan-88.
K. Eric Drexler, "Rod logic & thermal noise in the mechanical nanocomputer", Proc. of the 3rd Symp. on Molecular Electronic Devices, Forrest Carter, ed., Elsevier Science Pub. B.V. (North Holland, Amsterdam, 1988).
B. H. Robinson and N. C. Seeman, "Design of a biochip: a self-assembling molecular-scale memory device", Protein Engineering 1, 295-300 (1987).
Marc Stiegler, "Hypermedia and the Singularity", Analog, Jan-89.
SF Novels by John Cramer: my two hard SF novels, Twistor and Einstein's Bridge, are newly released as eBooks by Book View Cafe and are available at : http://bookviewcafe.com/bookstore/?s=Cramer .
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