Safe Utilization of Advanced Nanotechnology
The "gray goo" scenario and other dangers of advanced nanotechnology can be avoided with a centrally controlled, relatively large, self-contained nanofactory, administered by a central authority and with restricted-design software.
Originally published on Center
for Responsible Nanotechnology site. Edited version published
on KurzweilAI.net Jan. 28, 2003.
Abstract
Many words have been written about the dangers of advanced nanotechnology.
Most of the threatening scenarios involve tiny manufacturing systems
that run amok, or are used to create destructive products. A manufacturing
infrastructure built around a centrally controlled, relatively large,
self-contained manufacturing system would avoid these problems.
A controlled nanofactory would pose no inherent danger, so it could
be deployed and used widely. Cheap, clean, convenient, on-site manufacturing
would be possible without the risks associated with uncontrolled
nanotech fabrication or excessive regulation. Control of the products
could be administered by a central authority; intellectual property
rights could be respected. In addition, restricted-design software
could allow unrestricted innovation while limiting the capabilities
of the final products. The proposed solution appears to preserve
the benefits of advanced nanotechnology while minimizing the most
serious risks.
As early as 1959, Richard Feynman proposed building devices with
each precisely placed 1. In 1986, Eric Drexler published an influential
book, Engines of Creation2, in which he described some of the benefits and
risks of such a capability. If molecules and devices can be manufactured
by joining individual atoms under computer control, it will be possible
to build structures out of diamond, 100 times as strong as steel;
to build computers smaller than a bacterium; and to build assemblers* and mini-factories of various sizes, capable of making complex
products and even of duplicating themselves.
Drexler's subsequent book, Nanosystems3,
substantiated these remarkable claims and added still more. A self-contained
tabletop factory could produce its duplicate in one hour. Devices
with moving parts could be incredibly efficient. Molecular manufacturing
operations could be carried out with failure rates less than one
in a quadrillion. A computer would require a miniscule fraction
of a watt and one trillion of them could fit into a cubic centimeter.
Nanotech-built fractal plumbing would be able to cool the resulting
10,000 watts of waste heat. It seems clear that if advanced nanotechnology
is ever developed, its products will be incredibly powerful.
As soon as molecular manufacturing was proposed, risks associated
with it began to be identified. Engines of Creation2
describes one of the most famous: gray goo. A small assembler capable
of self-replication could in theory replicate itself too many times4. If it were capable of surviving outdoors and
of using biomass as raw material, it could eventually devour the
biosphere5. Others have analyzed the likelihood of an unstable
arms race6, and many have suggested economic upheaval resulting
from the widespread use of free manufacturing7. Some have even suggested that the entire basis of the
economy would change, and money would become obsolete8.
Sufficiently powerful products would allow malevolent people, either
hostile governments or angry individuals, to wreak havoc. Destructive
nanomachines could do immense damage to unprotected people and objects.
If the wrong people gained the ability to manufacture any desired
product, they could rule the world, or cause massive destruction
in the attempt9. Certain products, such as vast surveillance
networks, powerful aerospace weapons, and microscopic antipersonnel
devices, provide special cause for concern. Gray goo is relevant
here as well: an effective means of sabotage would be to release
a hard-to-detect robot that continued to manufacture copies of itself
by destroying its surroundings.
Clearly, the unrestricted availability of advanced nanotechnology
poses grave risks that may well outweigh the benefits of clean,
cheap, convenient, self-contained manufacturing. As analyzed in
Forward to the Future: Nanotechnology and Regulatory Policy10,
some restriction is likely to be necessary. However, as was also
pointed out in that study, an excess of restriction will enable
the same problems by increasing the incentive for covert development
of advanced nanotechnology. That paper considered regulation on
a one-dimensional spectrum, from full relinquishment to complete
lack of restriction. As will be shown below, a two-dimensional understanding
of the problem—taking into account both control of nanotech manufacturing
capability and control of its products—allows targeted restrictions
to be applied, minimizing the most serious risks while preserving
the potential benefits.
Nanotech Manufacturing and Its Products
The technology at the heart of this dilemma is molecular manufacturing.
A machine capable of molecular manufacturing—whether nanoscale or
macroscale—has two possible functions: to create more manufacturing
capacity by replicating itself and to manufacture products. Most
products created by molecular manufacturing will not possess any
capacity for self-replication, or indeed for manufacturing of any
kind; as a result, each product can be evaluated on its own merits,
without worrying about special nanotech risks. A nanotech-based
manufacturing system, on the other hand, could build weapons, gray
goo, or anything else it was programmed to produce. The solution
then is to regulate nanofactories; products are far less dangerous.
A nanotech-built car could no more turn into gray goo than a steel-and-plastic
car could.
Some products, however, will be powerful enough to require restriction.
Nanotech weapons would be far more effective than today's versions.
Very small products could get lost and cause nano-litter, or be
used to spy undetectably on people. And a product that included
a general molecular manufacturing capability would be, effectively,
an unregulated nanofactory—horrifyingly dangerous in the wrong hands.
Any widespread use of nanotech manufacturing must include the ability
to restrict, somehow, the range of products that can be produced.
If it can be done safely, widespread use of nanotech manufacturing
looks like a very good idea for the following reasons:
· The ability to produce duplicate manufacturing systems
means that manufacturing capacity could be doubled almost for free.
· A single, self-contained, clean-running nanofactory could
produce a vast range of strong, efficient, carbon-based products
as they are needed.
· Emergency and humanitarian aid could be supplied quickly
and cheaply.
· Many of the environmental pressures caused by our current
technology base could be mitigated or removed entirely.
· The rapid and flexible manufacturing cycle will allow many
innovations to be developed rapidly.
Although a complete survey and explanation of the potential benefits
of nanotechnology is beyond the scope of this paper, it seems clear
that nanotech has a lot to offer.
All of these advantages should be delivered as far as is consistent
with minimizing risks. Humanitarian imperatives and opportunities
for profit both demand extensive use of nanotechnology. In addition,
failure to use nanotechnology will create a pent-up demand for its
advantages, which will virtually guarantee an uncontrollable black
market. Once nanotech has been developed, a second, independent
development project would be both far easier and far more dangerous
than the original project. The first nanofactory must be made available
for widespread use to reduce the impetus for independent development11.
Development of nanotechnology must be undertaken with care to avoid
accidents; once a nanotech-based manufacturing technology is created,
it must be administered with even more care. Irresponsible use of
nanotech could lead to black markets, unstable arms races ending
in immense destruction, and possibly a release of gray goo. Deliberate
misuse of the technology by inhumane governments, terrorists, criminals,
and irresponsible teenagers could produce even worse problems—gray
goo is a feeble weapon compared to what could be designed. It seems
likely that research leading to advanced nanotechnology will have
to be carefully monitored and controlled.
However, the same is not true of product research and development.The
developer of nanotech-built products does not need expertise in
molecular nanotechnology. Once a manufacturing system is developed,
product designers can use it to build anything from cars to computers,
simply by reusing low-level nanotech designs that have previously
been developed. A designer may safely be allowed to play with pieces
1,000 atoms on a side (one billion atoms in volume), assuming they
have featureless surfaces. This is several times smaller than a
bacterium and 10,000,000 times smaller than a car.
Working with modular "building blocks" of this size would allow
almost anything to be designed and built, but the blocks would be
too big to do the kind of molecular manipulation that is necessary
for nanotech manufacturing or to participate in biochemical reactions.
A single block could contain a tiny motor or a computer, allowing
products to be powered and responsive. As long as no block contained
machinery to do mechanochemistry, the designer could not create
a new kind of nanofactory.
Once designed and built, a nanotech product could be used by consumers
just like a steel or plastic product. Of course, some products,
such as cars, knives, and nail guns, are dangerous by design, but
this kind of danger is one that we already know how to deal with.
In the United States, Underwriter's Laboratories (UL), the Food
and Drug Administration, and a host of industry and consumer organizations
work to ensure that our products are as safe as we expect them to
be. Nanotech products could be regulated in the same way. And if
a nanofactory could only make approved products, it could be widely
distributed, even for home use, without introducing any special
nanotech risks.
Nanofactory Technology: Regulating Risk, Preserving Benefit
It is generally assumed, incorrectly, that devices built with nanotechnology
must be quite small. This has led to fears that nanotech manufacturing
systems will be hard to control and easy to steal. In fact, as analyzed
by Drexler and others in the field, the products of nano-scale mechanochemical
plants can be attached together within the enclosure of a single
device. Small building blocks can be joined to make bigger blocks;
these blocks can be joined with others, and so on to form a product.
This process is called convergent assembly, and it allows
the creation of large products from nano-scale parts. In particular,
convergent assembly will allow one nanofactory to build another
nanofactory. There is no need to use trillions of free-floating
assembler robots; instead, the assemblers are securely fastened
inside the factory device, where they feed the smallest conveyor
belts.
A typical nanofactory might be the size of a microwave oven. Since
the assemblers are fastened into the factory and dependent on its
power grid, they have no need to navigate around the product they
are building—this improves efficiency—and they have no chance of
functioning independently. In addition, the entire nanofactory can
be controlled through a single interface, which allows restrictions
to be built into the interface. It can simply refuse to produce
any product that has not been approved. (The improved security of
tethered nanotech factories has been a theme in at least one work
of science fiction12.)
If a nanofactory will only build safe products, and will refuse
to build any product that has not been approved as safe, then the
factory itself can be considered safe. It could even build a duplicate
nanofactory on request. With the restrictions built in, the second
one would be as safe as the first. As long as the restrictions work
as planned, there is no risk of gray goo, no risk of undesirable
weapons or unapproved products, and no risk of producing unrestricted
nanofactories that could be used to make bad products.
At the same time, products that were approved could be produced
in any quantity desired. The products could even be customized,
within limits—and the limits could be quite broad, for some kinds
of products. If desired, the nanofactories (and the products) could
have tracking devices built in to further deter inappropriate use.
With nanofactories that can only produce approved designs, the
safety of nanotech manufacturing does not depend on restricting
the use of the factories. Instead, it depends on choosing correctly
which products to approve. The nanofactory itself, as a product,
can be approved for unlimited copying. This means that the abundant,
cheap, and convenient production capability of advanced nanotechnology
can be achieved without the risks associated with uncontrolled nanotech
manufacturing. A two-dimensional view of the risks of nanotechnology,
which separates the means of production from the products,
allows the design and implementation of policy that is minimally
restrictive, yet still safe.
A safe nanofactory design must build approved products while refusing
to build unapproved products. It must also be extremely tamper-resistant;
if anyone found a way to build unapproved products, they could make
an unrestricted, unsafe nanofactory and distribute copies of it.
The product approval process must also be carefully designed to
maximize the benefits of the technology while minimizing the risk
of misuse. Restricted nanofactories avoid the extreme risk/benefit
tradeoff of other nanotech administration plans, but they do require
competent administration.
One way to secure a nanofactory is to build in only a limited number
of safe designs. The user could ask it to produce any one of those
designs, but with no way to feed in more blueprints, the factory
could never build anything else. This simple scheme is fairly reliable,
but not very useful. It also poses the risk that someone could take
apart the factory and find a way to reprogram its design library.
A more useful and secure scheme would be to connect the nanofactory
to a central controller, and require it to ask for permission each
time it was asked to manufacture something. This would allow new
designs to be added to the design library after the nanofactory
was built. In addition, the nanofactory would have to report its
status back to the central controller. The system could even be
designed to require a continuous connection; a factory disconnected
from the network would permanently disable itself.
This would greatly reduce the opportunity to take the factory apart,
since it could report the attempt in real time and failed attempts
would result in immediate arrest of the perpetrator. This permanent
connection would also allow the factory to be disabled remotely
if a security flaw were ever discovered in that model. Finally,
a physical connection would allow the location of the factory to
be known and jurisdictional limits to be imposed on its products.
Current cryptographic techniques permit verification and encryption
of communication over an unsecured link13.
These are used in smart cards and digital cellular phones, and will
soon be used in digital rights management14.
Using such techniques, each nanofactory would be able to verify
that it was in communication with the central library. Only designs
from the library could be manufactured. In addition, each design
could come with a set of restrictions.
For example, medical tools might only be manufactured at the request
of a doctor. Commercial designs could require payment from a user.
Designs under development could be manufactured only by the inventor,
until they were approved and released. A design that did not come
from the central library would not have the proper cryptographic
signature and the factory would simply refuse to build it.
Rapid innovation is a key benefit of nanotechnology. The rapid
and flexible manufacturing process allows a design to be built and
tested almost immediately. Because designers of nano-built products
do not have to do any actual nanotech research, a high level of
innovation can be accommodated without giving designers any access
to dangerous kinds of products. As mentioned above, a design with
billion-atom, sub-micron blocks—permitting specification of near-biological
levels of complexity—would still pose no risk of illicit self-replication.
The minimum building block size in a design could be restricted
by the design system. A fully automated evaluation and approval
process could also consider the energy and power contained in the
design, its mechanical integrity, and the amount of computer power
built in. The block-based design system provides a simple interface
to the block-based convergent assembly system. A variety of design
systems could be implemented using the same nanofactory hardware,
and the designer would not have to become an expert on the process
of construction to create buildable designs.
With a safe-design nanofactory, adults—and even children—could
safely play with advanced robotics, inventing and constructing almost
anything they could imagine. (Today, adults as well as children
find it worthwhile to play with the Lego MindStorms system15.) More powerful products would require an engineering
certification. This could be given to any responsible adult, since
even a malicious product engineer would be unable to bypass the
factory's programming and cause it to make illicit fabricators.
A product that included chemical or nanomechanical manipulation
ability would have to be carefully controlled, even during the design
phase, to prevent the designer from building something that could
be used for illicit nanomanufacturing.
Risks and dangers associated with products could be assessed on
a per-product basis. Many products produced with simplified design
kits could be approved with only automated analysis of their design.
Most others could be approved after a safety and efficacy assessment
similar to today's approval processes. Only rarely would a new degree
of nanotechnological functionality be required, so each case could
be carefully assessed before the functionality was added to appropriately
restricted design programs.
Product approval for worldwide availability could depend on any
of several factors. First, unless designed with a child-safe design
program, it could be evaluated for engineering safety. Second, if
the design incorporated intellectual property, the owner of the
property could specify licensing terms. Third, local jurisdictional
restrictions could be imposed, tagging the file according to where
it could and could not be manufactured. Finally, the design would
be placed in the global catalog, available for anyone to use.
Conclusion
Nanotechnology offers the ability to build large numbers of products
that are incredibly powerful by today's standards. This possibility
creates both opportunity and risk. The problem of minimizing the
risk is not simple; excessive restriction creates black markets,
which in this context implies unrestricted nanofabrication. Selecting
the proper level of restriction is likely to pose a difficult challenge.
This paper describes a system that allows the risk to be dealt
with on two separate fronts: control of the nanotech manufacturing
capacity and control of the products. Such a system has many advantages.
A well-controlled manufacturing system can be widely deployed, allowing
distributed, cheap, high-volume manufacturing of useful products
and even a degree of distributed innovation. The range of possible
nanotech-built products is almost infinite. Even if allowable products
were restricted to a small subset of possible designs, it would
still allow an explosion of creativity and functionality.
Preventing a nanofactory from building unapproved products can
be done using technologies already in use today. It appears that
the nanofactory control structure can be made virtually unbreakable.
Product approval, by contrast, depends to some extent on human institutions.
With a block-based design system, many products can be assessed
for degree of danger without the need for human intervention; this
reduces subjectivity and delay, and allows people to focus on the
few truly risky designs.
In addition to preventing the creation of unrestricted nanotech
manufacturing devices, further regulation will be necessary to preserve
the interests of existing commercial and military institutions.
For example, the effects of networked computers on intellectual
property rights have created concern in several industries16,
and the ability to fabricate anything will surely increase the problem.
National security will demand limits on the weapons that can be
produced.
Forthcoming papers will give recommendations for a multi-purpose
system of administration that preserves commercial rights and security
imperatives while still allowing humanitarian and innovative use.
This paper has outlined a scenario for the safe development and
use of advanced nanotechnological manufacturing. Unrestricted nanotech
manufacturing creates several high-stakes risks. The use of a restricted
nanofactory design that is safe for widespread deployment can mitigate
some of these risks, and other risks can be dealt with piecemeal
by making many low-stakes decisions about the factory's products.
Careful attention must be paid to security during the initial nanofactory
development, and wise administration must be implemented to prevent
both undesired products and pressure for black markets or independent
development. With these caveats, however, the system presented here
preserves almost all the benefits of unrestricted nanotechnology
while greatly reducing the associated risks.
1 "There's Plenty of Room at the Bottom" is the title of a famous
speech given by Richard P. Feynman on December 29, 1959. A transcript
can be found at http://www.zyvex.com/nanotech/feynman.html.
2 K. Eric Drexler, Engines
of Creation, Anchor Press, 1986.
3 K. Eric Drexler, Nanosystems: Molecular Machinery, Manufacturing,
and Computation, John Wiley & Sons, 1992.
4 These fears have already been exploited in popular fiction.
5 For an analysis of these and other risks, see "Accidents, Malice,
Progress, and Other Topics" at http://www.foresight.org/Updates/Background2.html.
6 The best paper to date on the topic is "Nanotechnology and
International Security" by Mark Gubrud. See http://www.foresight.org/Conferences/MNT05/Papers/Gubrud/.
7 Perhaps the leading writer in this area is economist Robin
Hanson. A good overview of the potential impact of emerging technologies
on the world economy is "What It Takes to Get Explosive Economic
Growth," online in the Journal of Evolution and Technology
at http://www.jetpress.org/volume2/singularity.htm.
8 See, for example, "Nano-Economics" at http://www.geocities.com/computerresearchassociated/NanoEconomics.htm.
9 "Nanotechnology: the potential for new WMD" from Jane's Information
Group at http://www.janes.com/security/international_security/news/jcbw/jcbw030115_1_n.shtml.
10 "Forward to the Future: Nanotechnology and Regulatory Policy,"
by Glenn Harlan Reynolds, was published in November 2002 by the
Pacific Research Institute. It is available online at http://www.pacificresearch.org/pub/sab/techno/forward_to_nanotech.pdf.
11 The authors will analyze these issues in detail in forthcoming
papers.
12 The Diamond Age, Neal Stephenson, Bantam Spectra,
1995 and subsequent publishers.
13 See "Encryption Advances to Meet Internet Challenges" at
http://www.computer.org/computer/articles/August/technews800.htm.
14 See "Security Attributes Based Digital Rights Management"
at http://www.ub.utwente.nl/webdocs/ctit/1/00000079.pdf.
15 See LEGO MindStorms at http://mindstorms.lego.com/eng/default.asp.
16 See "Libraries in Today's
Digital Age: The Copyright Controversy" at http://ericit.org/digests/EDO-IR-2001-04.shtml.
Glossary
*Definitions of technical terms used in this article.
Assembler: A small nano-robotic device that can use surrounding
chemicals to manufacture nanoscale products. Advanced assembler
designs could work together to build macroscale products; this would
require motion and navigation capabilities.
Convergent assembly: A process of fastening small parts
to obtain larger parts, then fastening those to make still larger
parts, and so on. Convergent assembly can be used to build a product
from many, much smaller, components.
Macroscale: Larger than nanoscale; often implies a design
that humans can directly interact with. Too large to be built by
a single assembler (one cubic micron of diamond contains 176 billion
atoms).
Mechanochemistry: Chemistry accomplished by mechanical systems
directly controlling the reactant molecules.
Molecular manufacturing: The building of complex structures
by mechanochemical processes.
Nanofactory: A self-contained macroscale manufacturing system,
consisting of many molecular manufacturing systems feeding a convergent
assembly system.
Nanomechanical: Being mechanical and very small; for example,
a robot that can manipulate single molecules.
Nanoscale: Significantly smaller than a micron; on the scale
of large molecules; capable of interacting with molecules; capable
of being built by a single assembler.
About CRN
The Center for Responsible Nanotechnology (CRN) is a non-profit
organization dedicated to bringing about safe and effective molecular
manufacturing (nanofactory technology) that benefits all the world's
people. CRN is involved in studying, formulating, and writing about
wise policies for nanotechnology administration. For more information,
see http://www.CRNano.org.
© 2003 Center for Responsible Nanotechnology. Published
on KurzweilAI.net with permission.
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