Foresight Update 8
page 1
A publication of the Foresight Institute
 Nanotechnology
Symposium at MIT
by David Lindbergh
"Nanotechnology: Molecular Engineering and its
Implications," the fifth MIT Nanotechnology Study Group
(NSG) symposium, was held January 30 and 31 at the Massachusetts
Institute of Technology in Cambridge, Massachusetts.
Well over 150 people, many of them standing, crowded into the
lecture hall as NSG member Christopher Fry opened the symposium.
The two-day event presented a dozen speakers covering both the
latest progress in nanotechnology development and some of the
possible implications of this powerful new technology.
Fry set the ground rules for the symposium, saying "I want
to impress upon you that you have a responsibility to find holes
in arguments that are presented by speakers and force them to
respond to those holes. What you are not allowed to do is walk
out of here with any major unasked questions."
The first lecture, presented by Foresight Institute president K. Eric Drexler, was an
introduction to nanotechnology and an exposition on the technical
foundations of molecular engineering. There were many chemists in
the audience, and Drexler contrasted assembler techniques with
conventional solution chemistry. Assemblers will move selected
molecules to a specific position to cause a particular reaction,
while solution chemistry relies on random diffusive transport to
bump the right molecules against each other in large numbers.
Apparently some of the chemists in the audience were
uncomfortable with the "foreign" notion of using gears,
bearings, and other analogs of macro-scale devices on the
molecular level. In Drexler's words "Chemists have never
been able to build large, rigid, precise structures; so they are
used to thinking in terms of small or floppy molecules moving by
diffusion."
Next, Howard C. Berg from Harvard University's Department of
Biology described a 2 billion year old "nanotechnology"
device, the flagellar motor. These motors are found in E. coli
bacteria, where tiny rotary engines turn corkscrew propellers to
push the bacteria through fluids which (at that scale) have a
viscosity equivalent to a human swimming through light tar.
Just 22.5 nanometers in diameter, the motor can be made to run at
speeds of 300 to 3000 RPM, and produces maximum torque at stall.
It has about 30 different parts, eight independent
force-generating elements, and can run in forward or reverse. The
motor uses about 1000 protons to drive each revolution.
Dr. Berg's model of the motor's operation involves simple
arrangements of channels, binding sites, and springs. This
natural biological device shows that physical law allows
nanometer scale machines with complex moving parts.
Gary Tibbetts from General Motors Research Laboratories discussed
his work growing hollow carbon tubes as small as ten nanometers
in diameter. The walls of these tubes can be as few as 10 atoms
thick. His purpose is to develop an inexpensive way to make
carbon fibers for very strong, light automobile structures, but
these filaments might be a useful addition to a
"toolkit" for early nanotechnology.
Gary Marx from the MIT Department of Urban Studies and Planning
discussed privacy and security issues arising from
nanotechnology. He fears that competitive pressures and
complacency could easily cause the technology to be misused,
resulting in a "Big Brother" society in which everyone
is spied upon, personal information becomes public, irrelevant
information is used to screen and stigmatize people, and
technology is controlled by a privileged elite. He advised
caution in dealing with new technologies, and vigilance against
slow, creeping losses of privacy and control.
The MIT audience seemed to take many of Marx's points seriously,
but NSG member Jeff MacGillivray pointed out that when advanced
technology makes it possible to produce convincing fake records
(video, computer, etc.), human witnesses will become more
trustworthy than the output of automated surveillance.
Eric Garfunkel from Rutgers University's Laboratory for Surface
Modification discussed some of the latest advances in scanning
tunneling microscopy (STM). The STM is a device that can
piezoelectrically position an atomically sharp tip with atomic
precision and image a surface by moving the tip close enough
(about one nanometer) to cause electrons to tunnel between the
tip and surface. As the surface varies in height, the tip moves
up and down to maintain a steady tunneling current. Recently STMs
have been used to modify surfaces on a nanometer scale.
Garfunkel's group has succeeded in gouging trenches in silicon
that are 10 nanometers wide and one atomic layer deep by bumping
the tip into the surface.
Dongmin Chen from the Rowland Institute for Science in Cambridge
has been using similar techniques to produce atomic scale tunnel
diodes. He has also used the STM to make 0.4 nanometer high bumps
on silicon surfaces in regular patterns. Several audience members
were concerned these tiny features would quickly disappear as
atoms move around to fill holes and smooth out bumps. Chen
responded that in materials like silicon the features are quite
stable and have lasted as long as he can measure. In some other
materials (such as gold, which has an unusually mobile layer of
atoms at its surface) the features can disappear in 10 or 15
minutes.
Bruce Gelin from Polygen Corporation provided an overview of the
state of the art in molecular modeling. He explained that while
Schrödinger's "perfect" mathematical model of atomic
behavior has been known for over 60 years, this quantum
mechanical model is so computationally expensive that it's
impractical to use it for anything bigger than a single hydrogen
molecule, even with modern computers. So the challenge for
molecular modelers is to find computationally tractable
approximations for molecular behavior that are close enough to
give the same practical results as nature. With current
algorithms and workstation-type computers, one femtosecond (one
millionth of a nanosecond) in the life of a small protein can be
simulated in about one second. Gelin then presented a quick
"how to do it" session for the would-be molecular
modelers in the audience.
Kevin Ulmer, director of the Laboratory for Bioelectronic
Materials with the Japanese RIKEN research agency, discussed
RIKEN's 15 year project to produce self-assembling electronic
materials using protein engineering techniques. Their ultimate
goal is to produce a massively parallel cellular automata machine
by making "wallpaper" of proteins with different
electrical properties tiling a two-dimensional plane. For the
shorter term, Ulmer said he would be satisfied to be able to tile
a plane with arbitrary patterns of specified proteins.
Michael Rubner from the MIT Department of Materials Science
discussed his molecular electronics work with 1 to 2 nanometer
thick Langmuir/Blodgett films, in which he is trying to build up
multiple layers of conducting polymers to make electronic
devices.
Abraham Ulman from Eastman Kodak Research Laboratories has been
working on the construction of 3 nanometer monolayers for fiber
optic applications. He spoke about his progress and the
complexities of computational modeling of these monolayers.
Greg Fahy, a cryobiology researcher with the American Red Cross,
discussed medical and life extension applications of
nanotechnology. While powerful cell repair machines may represent
a distant goal for nanotechnological medicine, Fahy pointed out
that many biochemical events associated with aging are already
somewhat understood, and might be partially counteracted with
drugs even before nanotechnology arrives. Fahy suggested some
early goals for medical nanotechnology might be devices to
transport specific molecules, programmable DNA inserters,
removers, and "methyl-decorators," and
"trans-membrane gates" to transport molecules into and
out of cells.
Symposium chairman K. E. Nelson wrapped up the event with some
cautionary advice about the potential dangers of nanotechnology.
He reminded the audience that new technologies have dangers as
well as benefits, and that while on the whole the benefits are
usually greater, anything as powerful as nanotechnology must be
handled very carefully, lest the dangers sweep us away before we
can enjoy the benefits. The possibility of replicating devices
and nanotechnology's powerful generality mean that foolishness
(despite good intentions) or actual malign intent, could too
easily result in disaster. Nanotechnology could allow people to
change themselves, and our definitions of humanity. Nelson
advocated careful and controlled development of the technology
and better awareness on the part of the scientific community of
the potential impact and likely results of their work. He
reminded the MIT audience that it was their responsibility to
make nanotechnology work, not just happen.
This symposium was supported by the MIT Department of Chemical
Engineering, MIT Artificial Intelligence Laboratory, MIT IAP
Funding Committee, and the MIT Graduate Student Council.
This year's symposium focused more than previously on near-term
techniques leading to the actual development of nanotechnology.
Symposium organizer Zeke Gluzband noted afterward that "an
order of magnitude more serious people seemed interested than a
year ago." Nelson commented that he "discovered a much
greater degree of acceptance of nanotechnology than in previous
years. People seemed comfortable with talking in public about the
subject."
As nanotechnology comes closer to reality, symposia like this one
expose increasing numbers of scientists to the potential and
eventual consequences of their work. Hopefully this awareness
will help to channel the applications of the technology into
benign directions.
David Lindbergh is a consulting software engineer in the
Boston area and a member of the MIT Nanotechnology Study Group.
International
Interest in Nanotechnology
The World Economic Forum, held annually in Davos, Switzerland,
is a major meeting of several hundred world leaders in
government, industry, and business. At one point during the
meeting this February, 70 ministers and heads of state were
present, lending support to the meeting's unofficial description
as the "world economic summit." At this year's event,
three sessions included nanotechnology as a major topic.
At a Plenary Session on February 6, entitled "Technological
Turbulences," Eric Drexler spoke on nanotechnology (with
simultaneous translation into seven languages). The other session
speakers were James Watson (co-discoverer of the structure of
DNA) and Mark Wrighton, head of MIT's chemistry department, with
physicist Sergei Kapitsa as session chair. According to Kapitsa,
a ten-minute segment on nanotechnology was subsequently aired on
the Soviet Union's Radio Liberty channel.
Following the plenary, Drexler met with a smaller group to brief
them in more detail on expected developments. The next day, FI's
editor Chris Peterson held a briefing focusing on the expected
environmental benefits of using molecular manufacturing to
replace today's relatively inefficient and dirty manufacturing
processes.
On February 8 Drexler gave a more technical presentation to an
audience at the University of Basel, sponsored by Prof. H.-J.
Güntherodt, a pioneering researcher in the field of scanning
tunneling microscopy. The next day a similar presentation was
given at IBM's Zurich Research Laboratory, sponsored by physicist
Heinrich Rohrer, one of the Nobel-prizewinning inventors of the
STM. Part of the laboratory tour included a look at the recent
remarkable electron microscopy work of Hans-Werner Fink, as yet
unpublished. This work may be of great use in developing
nanotechnology, and will be reported here as soon as possible.
Videotapes of the World Economic Forum plenary session are
available from Gretag Displays Ltd, 8105 Regensdorf, Switzerland,
at a cost of 100 Swiss francs. Specify session 12; indicate NTSC
format for U.S. standard VHS format.
Upcoming
Events
Nanotechnology and the Frontiers of the Possible,
April 3 lecture by Drexler at Iowa State University, Ames. 8 PM,
followed by reception. Contact Prof. Robert Leacock at the Dept.
of Physics, 515-294-3986.
Evolutionary Economics: Learning from Computation,
April 23-24, George Mason University, Fairfax, VA. See symposium
writeup in this issue. Contact Center for the Study of Market
Processes, 703-323-3483.
Starburst Dendrimers and Their Polymers, 19th
International Polymer Symposium, June 6, Michigan Molecular
Institute. Covers chemistry of relevance to molecular
engineering, including precision design of macromolecules; held
in conjunction with regional meeting of ACS. Contact Co-Chairman
Donald Tomalia, 517-832-5573.
STM '90, Fifth International Conference on
Scanning Tunneling Microscopy/Spectroscopy, July 23-27, Hyatt
Regency Hotel, Baltimore, MD. Sponsored by the American Vacuum
Society and the U.S. Office of Naval Research. Contact Chairman
James Murday, 202-767-3026, fax 202-404-7139.
NANO I, First International Conference on
Nanometer Scale Science and Technology, held in conjunction with
STM '90 described above. Includes investigation of fabrication
and characterization of nanometer scale phenomena in surface
chemistry and physics, solid-state physics, metrology, materials
science and engineering, biology and biomaterials, mechanics,
sensors, and electronics technology. Same contact as STM '90.
Frontiers of Supercomputing II: A National
Reassessment, August, Los Alamos National Laboratory, sponsored
by NSF, DOE, NASA, DARPA, NSA, the Supercomputing Research
Center, and Los Alamos. Small strictly invitational meeting;
Ralph Merkle will speak on nanotechnology at a session on the
future computing environment.
From Foresight Update 8, originally
published 15 March 1990.
Foresight thanks Dave Kilbridge for converting Update 8 to
html for this web page.
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