| |
|
Engines of Creation 2.0: Letter From Author
Engines of Creation in 1986 inspired an explosion of interest in nanotechnology. Version 2.0 updates this classic book, including new concepts for molecular manufacturing and new uses for nanotech, such as removing carbon dioxide from the atmosphere and compressing it to liquid density for long-term storage.
Originally published in Engines
of Creation 2.0, WOWIO LLC, February 2007. Published with
permission on KurzweilAI.net March 15, 2007.
The vision I portrayed in Engines of Creation in 1986
inspired a generation of students to direct their careers toward
nanotechnology. Perhaps because it explores consequences of physics
and broad principles, rather than tracking then-current technologies
and trends, Engines continues to sell briskly as a book
on the future of technology.
It would be difficult to understand where nanotechnology is today
without understanding how we got here. Today's pattern of research
and opinion bears the imprint of ideas in Engines of Creation,
in part directly, but in large part through reactions, misconceptions,
reactions to misconceptions, and the peculiar dance of politics,
technologies, and funding that followed. I'd like to offer a sketch
of this process as it looked from my perspective, then a brief view
looking forward.
A Sketch of the History, 1986-2006
Engines of Creation envisioned a new landscape of future
nanotechnologies, and within a few years of its publication many
regarded the term "nanotechnology" as synonymous with
the highest of high technologies. Many researchers were already
studying the science and technology of nanoscale things (large molecules,
thin coatings, advanced transistors, small particles, thin fibers,
etc.) and they found that interest in their work multiplied when
they described it as "nanotechnology". Partly through
relabeling, partly though new initiatives, research in nanotechnologies
became more coherent and grew explosively. Conferences sprang up,
and companies, and government programs. Old fields found fresh vigor,
and new capabilities multiplied. In 2001, the U.S. launched a multi-billion
dollar National Nanotechnology Initiative (the NNI), and parallel
efforts emerged across Europe and Asia, where nanotechnologies were
at a similar level. The new nanotechnology establishment in government
and industry projected a trillion dollar market within ten years.
Critics reacted, warning that nanotechnology was opening a "Pandora's
box".
From a distance, it seemed that the vision presented in Engines
of Creation had broadened and grown, inspiring leaders to direct
vast resources toward a revolution in manufacturing, toward developing
nanoscale machinery, guided by digital data, that would join molecular
building blocks to make products with atomic precision and unprecedented
capabilities. A closer look showed a different reality: In the U.S.,
at least, molecular manufacturing became a taboo subject for a decade.
The cause was a reaction to a public misconception that had gotten
its start from a misreading of Engines.
In Engines of Creation, I pictured molecular manufacturing
using "replicating assemblers" to build things, including
more machines like themselves. I explained why sensibly designed
machines of this sort would use and require specially prepared materials
and be "useful but harmless". Further study showed that
this approach would be needlessly complex and inefficient. There
is simply no need to build tiny self-replicating machines. In a
detailed, technical book, I described and analyzed desktop-scale
molecular manufacturing systems that would be far simpler and more
efficient. (If you like math-intensive books, I recommend it: Nanosystems:
Molecular Machinery, Manufacturing, and Computation, Wiley/Interscience,
1992). But meanwhile, the earlier ideas from Engines had
spread into popular culture—science fiction, movies, and video games—and
taken on a life of their own. The ideas that spread fastest simplified,
transmogrified, and sensationalized. Soon, "nanotechnology"
was all about making so-called "nanobots"—self-replicating
bug-like things that could work miracles, but would inevitably run
amok, eat the world, and turn it into "gray goo." And
these monster nanobugs were, of course, said to be my idea.
How did the spread of these fantasies affect policy within U.S.
government circles? Not well. Not well at all. The new nanotechnologists,
working with particles, coatings, and the like, couldn't deliver
the promise of nanotechnology as understood by the public, and they
certainly weren't about to unleash swarms of ravenous nanobugs.
Quite naturally, they didn't like the popularized version of advanced
nanotechnology, especially in its absurd, mutant forms, and they
blamed me. From where they sat, "it" (that Drexler stuff)
was a single blob of inflammatory ideas. The popular culture images
were genuinely full of nonsense, and when they responded with a
simple message—that "it" was all nonsense—they had some
success in getting rid of false expectations and fears. This convenient
idea became a consensus among the funders and elders of the burgeoning
nanotechnology community.
And so it came to pass that the founding organizers of the United
States National Nanotechnology Initiative took care to invite not
one speaker, spend not one dime, have not one word on their website
that might suggest that the idea molecular manufacturing should
even be considered. Indeed, as you can see from the exchange reprinted
in Appendix C, a leading establishment spokesman, Nobel Laureate
Richard Smalley, denounced the idea. He insisted that molecular
manufacturing was all about making things called "nanobots"—self-replicating,
monstrous, bug-like things that would inevitably run amok. He of
course said that they were my idea. And impossible.
My 2003 exchange with Prof. Smalley marked a milestone on the return
to realism. Before it appeared in print, the establishment said
that he had refuted the molecular physics of molecular manufacturing.
After, it became plain that he had refuted only absurd ideas from
the popular press, and had nothing persuasive to say about the actual
technical concepts. Vocal rejection fell out of fashion and young
researchers found a new freedom to speak of ambitious objectives.
A second milestone came in 2006: an independent, high-level, scientifically
grounded report on the subject. Congress had directed the National
Research Council of the National Academy of Sciences to review the
performance of the NNI. A committee including experts in physics,
chemistry, and engineering met, invited and questioned experts on
molecular manufacturing, and subjected the concepts and analysis
in Nanosystems to careful, technical review. They examined
current understanding of atomistic control, error rates, speed of
operation, thermodynamic efficiency, and so on, and note that these
"can be calculated in theory, but not predicted with confidence."
The report closes with a call for funding "experimental demonstrations
that link to abstract models and guide long-term vision."
Finally, after 20 years, a competent committee had examined the
evidence, considered the science, and offered an informed judgment.
During these years, despite U.S.-centered confusion, a tide of
nanotechnologies has continued to rise. There have been many results:
Microelectronics became nanoelectronics. Computer power has grown
10,000 fold, enabling ever larger and more accurate design and modeling
of molecular systems. Biological molecular machines have been studied
and harnessed; simple artificial molecular machines have been designed
and synthesized; advanced molecular machines have been designed
and simulated. Designing and making new proteins developed from
an idea to a task that can be completed in weeks. DNA strands have
been designed that fold and link to form million-atom, three-dimensional
structures that can be designed and made in a single workday.
Meanwhile, the Soviet Union fell, Europe expanded, China awoke,
and the US stood as the unchallenged military power, while a few
decades-old spacecraft continued their endless fall into interstellar
space. Revolutionary advances in space continued to await a revolution
in spacecraft fabrication. Revolutionary advances in machine intelligence
continued to await new ideas. As for social intelligence, institutions
that aid factual judgment (on climate change, molecular manufacturing,
etc.) lagged far behind mass media that treat dispute as a sport.
Computers, once rare (Engines began with a typewriter and
was delivered on paper) multiplied and linked through networks to
form a new world of worlds. A hypertext publishing system—the World
Wide Web—emerged, growing explosively in size and abilities, reshaping
society. But they continued to lack what Engines describes
as crucial: readers of a controversial document can't easily see
the best-rated criticisms, and so critics can't respond where it
would matter most. And so the Web presents knowledge and nonsense
almost as equals, and amplifies both. At both the surface and depths
of the computational world, there's a need for new structures.
Looking Forward
Progress in nanotechnologies has created many powerful capabilities,
and I think that the time is ripe to combine them to move molecular
engineering to a new level. DNA engineering builds precise, million-atom
frameworks; engineered proteins can bind to precise locations on
these frameworks; and proteins can bind other components—strong
and stiff, electrically or chemically active—and biology shows that
proteins themselves can serve as construction machinery.
Taken together, these developments have opened the door to a new
domain of engineering, and through it to a path that leads, step
by useful step, to advanced molecular manufacturing.
Technical studies indicate that nanofactories, ranging to desktop
scale and larger, will be able to convert simple chemical feedstocks
into large, atomically precise products cleanly, inexpensively,
and with moderate energy consumption. They indicate that a 10 kilogram
factory will be able to produce 10 kilograms of products in hours
or less—a stack of billion-processor laptops, a package containing
a trillion cell-sized medical devices, or a roll containing hundreds
of square meters of tough, flexible stuff that converts sunlight
to electric power. It seems that raw materials will be the main
cost of production. At a dollar per kilogram (a typical price for
industrial feedstocks today) the solar-electric material would cost
about one cent per square meter, and the computers would cost about
a dime. Shipping and handling extra.
It may be surprising that a nanofactory could make so wide a range
of products. Manufacturing machines today are specialized: plastic-molding
machines shape particular kinds of plastic, metal-cutting machines
shape particular kinds of metal, and so on. But imagine what people
50 years ago would have thought if someone said that a single machine
could replace a typewriter, a television, a drawing board, a calculator,
a darkroom, a record-player, a pinball machine, and a library. This
notion wouldn't have passed the laugh test then, but today we call
these machines "computers". They can do all this because
their tiny, fast-cycling parts can be directed to form complex patterns
of the elementary building blocks of information, bits. Likewise,
molecular manufacturing systems will use tiny, fast-cycling parts,
but these can be directed to form complex patterns of the elementary
building blocks of matter. As with computers, the effects on the
world will be far beyond what anyone can now imagine.
I'd like to describe one that Engines didn't mention,
a system that could address global warming. Molecular machinery
can be used to sort gas molecules to extract carbon dioxide from
air. This requires substantial energy—the process compresses a gas—but
it can be done with good thermodynamic efficiency. To remove 100
parts per million of carbon dioxide from the atmosphere as a whole,
compressing it to liquid density for long-term storage, would require
several terawatts of power for 10 years. This could be provided
by solar arrays with the total area of a square roughly 200 kilometers
on a side. By providing the necessary molecular machinery and dropping
the cost of the arrays, molecular manufacturing can make it affordable
to remove and store the excess carbon dioxide that has accumulated
since the first industrial revolution.
Abilities of this magnitude may arrive sooner than most would expect.
The last 50 years have shown the incredible dynamism of technologies
in the microworld. While cars, aircraft, houses, and furniture have
changed only moderately in their capabilities and costs, DNA and
microelectronic technologies have exploded, expanding their basic
capabilities by factors of more than a billion. The developments
leading to molecular manufacturing are of a similar sort and will
share this dynamism. Past a certain threshold, however, these developments
will burst forth from the microworld to transform technologies on
a human and even planetary scale. No realistic view of the future
can omit this prospect.
© 2007 K. Eric Drexler
| | |
