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Foresight Update 14 - Table of Contents | Page1 | Page2 | Page3 | Page4 | Page5 |
On June
26, 1992, the U.S. Senate Committee on Commerce, Science, and
Transportation's Subcommittee on Science, Technology, and Space
held a hearing on the topic of "New Technologies for a
Sustainable World." Dr. Eric
Drexler, Chairman of the Foresight
Institute and Research Fellow of the Institute for Molecular Manufacturing,
was invited to testify on molecular nanotechnology. The following
is the written testimony he submitted; a later issue will cover
the oral
portion.
In 1959, the Nobel prizewinning physicist Richard
Feynman suggested that individual atoms and molecules could
be positioned and used as building blocks; experimental results
now demonstrate that he was correct. Molecule-by-molecule control
can become the basis of a manufacturing technology cleaner and
more efficient than those known today. This molecular
nanotechnology will resemble processes in farms and forests, in
which molecular machines convert common raw materials--including
surplus atmospheric carbon dioxide--into useful products. It can
be a basis for sustainable development, raising the material
standard of living while decreasing resource consumption and
environmental impact.
Molecular nanotechnology will have broad applications. It will
provide a general-purpose method for processing materials,
molecule by molecule, much as computers provide a general-purpose
method for processing information, bit by bit. It will by its
nature be highly efficient in both materials and energy use. Its
products can include:
Analysis and simulation based on existing scientific knowledge
is enough to show what molecular nanotechnology can do, but
developing it will require the construction of better molecular
tools. The pace of development will depend not on unpredictable
breakthroughs, but on the magnitude and quality of a focused
development effort. The total development time is hard to
predict, but 15 years would not be surprising. Unlike some
technology development projects, in which few payoffs result
until the end of the development cycle, research in molecular
nanotechnology will bring major scientific benefits at an early
date.
Molecular nanotechnology is worth pursuing both for its immediate
scientific benefits and for its later environmental benefits.
Because there is reason to think that it will become the basic
manufacturing technology of the 21st century--on grounds of cost,
quality, efficiency, and cleanliness--its development also raises
issues of economic competitiveness. Japan's Ministry of
International Trade and Industry has recently committed some $185
million over ten years to a nanotechnology effort.
The U.S. research community has not yet reached a conclusion
regarding the potential of this field because it has not yet
addressed the basic scientific issues. If we conduct idle debates
on molecular nanotechnology while others conduct active research,
they will learn the answers to our questions. It is time to
assess the potential of molecular nanotechnology and to choose a
course of action. If its potential is even half as great as the
evidence now indicates, then medical, economic, and environmental
concerns will favor vigorous development.
Foresight Update 14 - Table of Contents |
Mr. Chairman, I would like to thank you and the members of
this subcommittee for this opportunity to discuss a topic that I
expect will one day become a leading issue in these halls. The
focus of this hearing--new technologies for a sustainable
world--is particularly appropriate for discussion of this topic,
because a concern with the consequences of future technologies
for the environment and for the human condition has for many
years guided my research, and has led to the results described
here.
In the decade since I first
described molecular nanotechnology in the Proceedings
of the National Academy of Sciences, this field has
progressed from general theoretical concepts to early laboratory
demonstrations and a growing body of detailed designs. Five years
ago, audiences questioned whether individual atoms could be
placed in precise patterns; today, I can answer that question not
just with calculations, but with a slide showing the letters
"IBM" spelled using 35 xenon atoms.
The Foresight Institute, which I serve as Chairman, sponsors a series of scientific
conferences on molecular nanotechnology. The most recent,
held last autumn, was cosponsored by the Stanford University
Department of Materials Science and Engineering and the
University of Tokyo Research Center for Advanced Science and
Technology; this meeting has stimulated at least three laboratory
research efforts directed toward a key milestone on the path to
molecular nanotechnology. Japan's Ministry of International Trade
and Industry recently committed some $185 million over the next
ten years to a nanotechnology research effort; development of
molecular systems is seen in Japan as fitting with the broad goal
of developing environmentally-compatible technologies.
Momentum toward the development of molecular nanotechnology is
building around the world. The consequences for human life and
for Earth's environment will be enormous, and could be enormously
positive. The balance of this testimony begins by describing
molecular nanotechnology from a biological and ecological
perspective and sketching some of its wide range of applications.
It then describes the relevant areas of research; the level of
activity in the U.S., Japan, and Europe; and some of the policy
issues that its development can be expected to raise. The closing
section discusses how these concepts can be evaluated before
committing to any substantial effort that presumes their
validity.
Foresight Update 14 - Table of Contents |
Industry today consumes fossil fuel and discharges carbon
dioxide into the atmosphere. Forests and farms, in contrast,
produce useful products (including fuels) while removing carbon
dioxide from the atmosphere. Proposals for reducing the
concentration of greenhouse gases typically focus on modifying
existing industrial technologies to reduce emissions, and this is
a sound strategy. Yet it may be better to develop industrial
technologies that, like forests and farms, are carbon dioxide
consumers.
Leaves are solar energy collectors employing molecular electronic
devices: chlorophyll molecules and photosynthetic reaction
centers. These solar energy collectors, like the other useful
products of forests and farms, are built by systems of molecular
machinery such as ribosomes and metabolic enzymes. A natural
direction for technology, then, is to learn to apply systems of
molecular machinery to build useful products in industry. The
example of green plants indicates some of the results that can be
expected from molecular nanotechnology:
Although no technology can, by itself, solve environmental
problems, a technology with these characteristics can be a great
help. If a high standard of living and reduced environmental
impact can be achieved with relatively little sacrifice, then any
given amount of political and regulatory pressure should yield
greater results in reducing the impact of human activities on the
natural world.
Taking the biological analogy as far as the preceding paragraphs
have done risks the misunderstanding that molecular
nanotechnology will be a form of biotechnology. The differences
are large: Molecular nanotechnology will use not ribosomes, but
robotic assembly; not veins, but conveyor belts; not muscles, but
motors; not genes, but computers; not cells dividing, but small
factories making products--including additional factories. What
molecular nanotechnology shares with biology is the use of
systems of molecular machinery to guide molecular assembly with
clean, rapid precision.
Another biological analogy seems appropriate: Aircraft and birds
share some basic principles of flight, and birds inspired the
development of mechanical flight. It would have been futile,
however, to attempt to develop aircraft by applying genetic
engineering to birds, or by concentrating exclusively on
ornithological research. The Wright brothers studied birds, but
they then set off in a fresh direction. Molecular nanotechnology
cannot be achieved by tinkering with life, and its products will
differ from biological organisms as greatly as a jet aircraft
differs from an eagle.
Foresight Update 14 - Table of Contents |
Molecular nanotechnologies will be based on molecular
manufacturing, a fundamentally new way to produce materials and
devices from simple raw materials. By guiding the assembly of
molecules with precision, it will enable the construction of
products of unprecedented quality and performance. Because it
will work with the fundamental molecular building blocks of
matter, it will be able to make an extraordinarily wide range of
products.
Computers provide an analogy. In the early decades of this
century, many specialized data processing machines were in use:
these included the Hollerith punched-card tabulators used in the
census, Vannevar Bush's analogue machine that solved differential
equations for scientists, and adding machines used in offices to
speed accounting chores. Each of these slow, inefficient,
specialized machines has now been superseded by fast, efficient,
general-purpose computers; even pocket calculators contain
computers. By treating data in terms of fundamental building
blocks--bits--general purpose computers can perform essentially
any desired operation on that data.
Today, manufacturing relies on many specialized machines for
processing materials: blast furnaces, lathes, and so forth.
Molecular nanotechnology will replace these slow, inefficient,
specialized (and dirty) machines with systems that are faster,
more efficient, more flexible, and less polluting. As with
computers and bits, these systems will gain their flexibility by
working with fundamental building blocks. When desktop computers
replaced adding machines, they did more than speed addition.
Molecular manufacturing will likewise open new possibilities.
The applications of precise fabrication at the molecular level
(mechanosynthesis) are as broad as technology itself, because all
of technology relies on manufacturing. Molecular-scale components
can be used to place the equivalent of a billion modern computers
in a desktop machine. Molecular-scale components will make
possible new medical and scientific instruments, including DNA
readers able to sequence genomes routinely. On a larger scale,
production of better materials will make possible lighter, more
efficient vehicles, without sacrificing structural strength: this
will aid transportation technologies ranging from spacecraft to
automobiles. Lighter structures will consume less material and
energy. Because the lightest and strongest materials will be made
from carbon (in the form of graphite and diamond fibers), carbon
dioxide can become a raw material rather than a waste product.
Molecular manufacturing systems can be used to make more
molecular manufacturing systems, hence the capital cost of
production can be low. An analysis of inputs, outputs, and
productivity suggests that the total cost of production can be in
the range familiar in agriculture and in the production of
industrial chemicals--tens of cents per pound. At this cost, many
applications become practical. For example, solar photovoltaic
cells fabricated in the form of tough sheets for roofing and
paving could provide solar electric power without consuming
additional land.
With clean solar power, clean manufacturing processes, and light,
efficient products, it will be possible to provide a high
material standard of living with decreased impact on the natural
world. This can contribute to the goal of sustainable
development.
Foresight Update 14 - Table of Contents |
These developments are not around the corner, but their
feasibility can be clearly foreseen, as can the nature of
research programs able to implement them. The essential goal is
to construct molecular structures with the precision already
familiar in chemical synthesis and protein engineering, but on a
larger scale. Accordingly, properly focused research in chemical
synthesis and protein engineering (within the fields of molecular
biology and biochemistry) is important to the implementation of
molecular nanotechnology, as is the emerging field of molecular
manipulation using proximal probe microscopes such as the
scanning tunneling and atomic force microscope.
Each of these areas is a classic small-science field, in which
small teams use inexpensive materials and equipment. The prospect
of molecular nanotechnology shows that small science can have big
rewards.
I have not requested and do not anticipate a need for Federal
funds to support my own studies in this area, but the field as a
whole could benefit from vigorous support of appropriate
computational simulation and laboratory research. Since this work
would be performed chiefly by existing researchers with existing
equipment, the need is more for a shift in direction than for a
growth in spending. Developments along the path to molecular
nanotechnology promise to yield early results in scientific
instrumentation, making it justifiable as a means of pursuing
existing goals in chemistry and in biomedical research.
Progress toward molecular nanotechnology in the U.S. has been
retarded chiefly by cultural obstacles. Molecular nanotechnology
will require the construction of complex molecular machines, but
chemistry and biochemistry are sciences, and focus on the study
of nature. To return to the example of aerospace engineering,
expecting molecular scientists to build molecular manufacturing
systems is somewhat like expecting ornithologists to build
aircraft. Building complex systems demands research that first
defines goals and then works backward to identify and implement
the means, usually dividing the work among many teams. Studying
nature, in contrast, can be performed by small research groups,
each jealously guarding the independence and purity of its
research. The development of molecular nanotechnology can keep
much of the character of small science, but it will require the
addition of a systems engineering perspective and a willingness
on the part of researchers to choose objectives that contribute
to known technological goals. Progress will require that
researchers build molecular parts that fit together to build
systems, but the necessary tradition of design and
collaboration--fundamental to engineering progress--is
essentially absent in the molecular sciences today.
Furthering molecular nanotechnology might best be achieved by
directing federal agencies that perform or fund research in the
molecular sciences to support efforts aimed at the construction
of molecular machine systems and instruments that can precisely
position molecules. The results of this initiative could lead to
cost savings in other programs. It has been proposed, for
example, that thousands of researchers be employed over many
years at great expense in order to read the human genome, yet the
molecular machinery found within a dividing cell reads (and
copies) the entire genome in a matter of hours. Scientific
instruments based on relatively simple molecular machines could
read DNA with comparable speed and store the results in a
computer memory. The development of such instruments, once the
necessary technology base is in place, could hardly consume the
efforts of thousands of researchers; it would more likely require
only a few cooperating laboratories. The result would enable
scientists to read and study many genomes.
Molecular machinery is a technology of basic importance and
deserves to be treated accordingly. This would be true even
without the longer-term goal of molecular manufacturing.
Assembled (a), cross sectional (b), and exploded (c) views of a design for a planetary gear system containing 11 moving parts and 3,557 atoms. Rotation of the inner shaft forces a rolling motion of the nine surrounding gears, driving rotation of the larger shaft (to the right) at a lower speed. A molecular machine component of this sort could not be made with existing chemical techniques, but could be part of a mechanical system made using molecular manufacturing. This design is the result of a collaboration between Dr. K. Eric Drexler of the Institute for Molecular Manufacturing and Dr. Ralph Merkle of the Xerox Palo Alto Research Center, using molecular simulation software developed by Molecular Simulations Inc.
Foresight Update 14 - Table of Contents |
The U.S. has impressive strengths in areas of science and
technology relevant to molecular nanotechnology. It was at IBM's
Almaden laboratory that Donald Eigler's group spelled
"IBM" using 35 xenon atoms. It was at William DeGrado's
laboratory at DuPont that scientists first designed and built a
new protein molecule, containing hundreds of precisely joined
atoms. Nanotechnology has become a buzzword, but is often used to
describe incremental improvements in existing semiconductor
technologies; although of great value in their own right, these
are of surprisingly little relevance to molecular nanotechnology.
(Micromachine research, often confused with nanotechnology in the
popular press, is even less relevant.)
Progress toward molecular nanotechnology in Japan is harder to
judge, owing to distance and language barriers, but the Japanese
commitment appears impressive. In my visits to Japan, I have
received a strikingly warm welcome. MITI organized a symposium
around my first visit, at which--despite my many talks in the
U.S.--I for the first time met other researchers who were
studying molecular machines not only to understand nature, but to
build molecular machine systems. On another visit, I spoke at the
only scientific meeting on the construction of molecular machine
systems that I have attended but did not myself organize. Japan's
NHK television network aired a three-hour series this spring,
titled "Nanospace," that included interviews with me
and material from my work; nothing comparable has appeared on
U.S. television.
While exploring a Japanese-language bookstore that I happened
across in Tokyo last spring, I found a table with eight books on
micromachines and molecular machines, all displayed face on. Half
were paperbacks (including conference proceedings containing a
summary of a talk I had given in Tokyo two years before), and
half contained one or more graphics illustrating molecular
machine designs drawn from my work. One of these was a
translation of my first book on molecular nanotechnology, Engines of Creation. I can
with confidence state that no bookstore in the U.S. contains a
similar display, because no such set of books exists in the
English language.
MITI's commitment of $185 million is a sign of strong interest.
In addition, Japan's Science and Technology Agency, through the
Exploratory Research for Advanced Technology program, has
sponsored a series of efforts in molecular engineering, including
the Aono Atomcraft Project, which aims to build semiconductor
devices with atom-by-atom control. I recently read that Texas
Instruments has established a laboratory with similar goals; the
location they chose is Tsukuba, north of Tokyo.
Researchers at Hitachi's Central Research Laboratory last year
spelled "Peace 91 HCRL" by removing individual atoms
from a surface. Researchers at the Protein Engineering Research
Institute in Osaka (no comparable institute exists in the U.S.)
have designed and built the largest protein molecules of which I
am aware. Nanotechnology has been a serious goal in Japan for
longer than it has in the U.S., and is seen as contributing to
technologies in greater harmony with the natural world.
I am less familiar with research in Europe, but key technologies
(such as the scanning tunneling microscope) have been developed
there. Dr. Hiroyuki Sasabe of the RIKEN Institute in Japan tells
me that there are several research consortia in Europe doing work
on molecular systems, and that he knows of no similar consortia
in the U.S.
Foresight Update 14 - Table of Contents |
Molecular nanotechnology will raise numerous policy issues. In
many areas, years of consideration will be necessary before wise
policies can be formulated. This section provides only a brief,
preliminary survey of a few issues of particular prominence.
Research in molecular nanotechnology will by its nature pose no
special risks so long as it remains unable to make large
quantities of product. In its early phases, it will most closely
resemble a branch of laboratory chemistry, and its chief product
will be information. Later, when large scale applications become
possible, major regulatory issues will arise. Further work will
be necessary to identify these issues, but because molecular
manufacturing can be used to produce high-performance systems of
many kinds, these issues will surely include arms control.
Because the U.S. has no clear lead in this technology and because
large-scale commercial applications are still distant,
international cooperation in research may be desirable. Further,
because potential long-term applications include weapon systems,
a failure to establish cooperative international efforts could
lead to dangerous outcomes. These considerations suggest the
desirability of a development program involving international
cooperation centering on shared global concerns with health and
the environment. One possible vehicle for this might be an
expanded version of the existing Human Frontier Science Program.
It seems that no special regulatory issues will arise for some
time, but this time should be used to gain an understanding of
the issues that will emerge as the technology matures.
Cooperative development can provide a basis for eventual
international controls, for example, of the use of molecular
manufacturing in arms production.
Foresight Update 14 - Table of Contents |
The U.S. scientific community has reached no consensus
regarding the prospects for molecular nanotechnology; indeed,
these ideas have stirred heated controversy. A recent OTA study
could identify no published scientific arguments on the other
side (vague and unscientific objections have been common), but it
would be unwise for a decision maker to advocate a major
commitment of resources to molecular nanotechnology without
further study and evaluation.
This autumn, the first quantitative, detailed, book-length
analysis of molecular manufacturing will be published (Nanosystems:
Molecular Machinery, Manufacturing, and Computation,
Wiley Interscience). This work lays out the fundamental
principles of molecular machinery and describes how molecular
machines can collect, orient, process, and assemble molecules
with high efficiency and reliability. If there is a major error
or omission in this analysis of molecular manufacturing, it
should be possible for a critic to describe the difficulty in
quantitative, scientific terms.
Experience shows, however, that the scientific community does not
move swiftly to evaluate interdisciplinary engineering proposals.
No single discipline sees it as a responsibility, and most
scientists see the work as a distraction from winning their next
grant. If these concepts are to be evaluated soon, and well
enough to enable decision makers to choose with confidence,
deliberate action seems necessary. A natural choice would be to
commission a study of molecular manufacturing, setting the
objective of evaluating its scientific and technological
feasibility by seeking specific, scientific criticisms and
responses from appropriate researchers.
A study of this sort could provide a basis for decisions and
could stimulate further debate and analysis that would provide a
still better basis for decisions. The Office of Technology
Assessment may be an appropriate agency to conduct this initial
study.
Foresight Update 14 - Table of Contents |
Molecular nanotechnology promises a fundamental revolution in
the way we make things, and in what we can make. By bringing
precise control to the molecular level--resembling the control
found in living organisms--it can serve as a basis for
manufacturing processes cleaner, more productive, and more
efficient than those known today. Like green plants, it can
produce inexpensive solar collectors and other useful products
while removing carbon dioxide from the atmosphere.
Because it will work with the basic building blocks of matter,
its applications are extraordinarily broad: they include improved
materials and computers. Early applications will include
scientific and medical instruments.
Pure science has prepared the ground for molecular
nanotechnology: it is now time to build. Initial goals include
the development of better techniques for positioning molecules
and for building molecular machines. Research in chemistry,
biochemistry, and proximal probe microscopy can all make
substantial contributions. Computational simulation has begun to
show in detail what can be
built and how it will work. Design, simulation, and
laboratory research can all benefit from support targeted on
genuinely relevant research. Progress will depend largely on the
willingness of molecular scientists to solve problems that
contribute to engineering objectives.
Research leading toward molecular nanotechnology is accelerating
world wide. Focused research is perhaps strongest in Japan.
Although large-scale capabilities (and the need for regulation)
are still years away, it is not too early to consider the
consequences of success and to build the framework of
international cooperation that will be necessary in order to
manage those consequences.
The preceding paragraphs assume that the analysis supporting the
case for molecular manufacturing is essentially correct, but
there is as yet no consensus on this. The evaluation of
interdisciplinary proposals is slow in the absence of a
deliberate effort. It is time to make that deliberate effort, to
evaluate the evidence and set research priorities accordingly. If
we merely wait and see, we will accomplish more waiting than
seeing. Economic competitiveness and the health of the global
environment may depend on timely action.
Foresight Update 14 - Table of Contents |
The term nanotechnology is here used to refer to an anticipated technology giving thorough control of the structure of matter at the molecular level. This involves molecular manufacturing, in which materials and products are fabricated by the precise positioning of molecules in accord with explicit engineering design.
Foresight Update 14 - Table of Contents | Page1 | Page2 | Page3 | Page4 | Page5 |
From Foresight Update 14, originally
published 15 July 1992.
Foresight thanks Dave Kilbridge for converting Update 14 to
html for this web page.
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