"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
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
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
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
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.
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
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
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
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.