Earlier this week, we announced that CRN has prepared a list of thirty essential studies that must be performed before we can have an adequate understanding of the potential societal impacts of nanotechnology.
Here is a look at some of recommended study #2: "To what extent is molecular manufacturing counterintuitive and underappreciated in a way that causes underestimation of its importance?"
To the extent that the importance of molecular manufacturing (MM) is underestimated, it may not be adequately studied or prepared for. Several factors may combine to create substantial underestimates of MM's significance.
Subquestion A: Benefits are concentrated at the end of development — will projections from partial progress or spinoffs underestimate benefits?
Preliminary answer: The benefits of molecular manufacturing come from automation and autoproductivity. For example: suppose that parts and labor to build a 1-kg nanofactory cost $1000 per gram, and a million-dollar factory can make 100 kg of product in its lifetime. Then factory cost contributes $10 per gram of product cost. If the factory can make 90% of its own parts with 90% automation, then factory cost drops to about $110,000. But if the factory can make and assemble 100% of its parts with full automation, then factory cost (and product cost) drop to cost of raw materials: probably a few dollars per kilogram.
The first 90% saves one order of magnitude product cost. The last 10% saves another three orders of magnitude. And because molecular manufacturing builds everything using the same bottom-up processes, the last 10% will probably be the easiest to design — very different from conventional engineering.
Subquestion B: Molecular manufacturing may be overshadowed by superficially similar technologies — is there a risk that people will think they're studying MM when they're actually studying something else?
Preliminary answer: Popular concepts of nanotechnology include molecular manufacturing and may even be identified with it, since that was the original meaning of the word as coined by Eric Drexler. However, the loose constellation of fields called 'nanotechnology' covers everything from photonics to nanoparticles to molecular electronics. Most nanoscale technology research today is unrelated to molecular manufacturing. Current work in nanotechnology pursues nanoscale products, not nanoscale productive systems (which can also make large products). Policymakers who want to promote molecular manufacturing, but are unaware of the distinction, may feel a false sense of security from reports of successes in nanotechnology.
Subquestion C: Molecular manufacturing is opposed by special interests — is study of it likely to be stunted by political maneuvering?
Preliminary answer: Study of molecular manufacturing has already been stunted by politics. Mark Modzelewski, co-founder of the U.S. NanoBusiness Alliance, has launched vituperative attacks against commentators who dare to suggest that molecular manufacturing is possible. Richard Smalley, advisor to the U.S. National Nanotechnology Initiative leadership, has called for chemists to oppose the "fuzzy-minded nightmare dream". The NNI website declares that "nanobots" are "science fiction" and refers to them as "creatures".
This probably has multiple motivations. Some researchers seem to be afraid that refocusing the NNI toward molecular manufacturing would threaten their research funding. Others might fear that admitting the possibility of nanobots (while failing to distinguish simple industrial mechanisms from complex life-like systems) would increase public fear of destructive or runaway nanotechnology. Some opposition probably stems from simple incomprehension.
Subquestion D: Engineering benefits of nanoscale physics (near-frictionless interfaces; perfectly precise construction; scaling laws) are not widely known — would better knowledge increase research and development?
Preliminary answer: The problems of nanoscale engineering are famous, perhaps overly so: thermal noise, sticky surfaces, etc. But some alleged problems, like friction, go away when atomically precise machines can be built. And almost no one talks about the benefits, which are substantial.
Covalent molecules are perfectly precise in their formulation: an atom is either in the right place, or you have a different molecule. This means that fabrication can benefit from absolute precision: there's no need to specify or account for a manufacturing tolerance.
Sliding interfaces that are atomically precise can be almost completely frictionless. This quality, called 'superlubricity', was analyzed by Drexler in connection with nanosystems and has recently been observed. Experience from high-friction MEMS is misleading, since MEMS surfaces are quite imprecise and rough.
Unfamiliar nanoscale effects, including thermal noise and springiness of molecules, are generally seen as problems; their engineering benefits are substantial but not generally appreciated. For example, thermal noise reduces friction and can allow jammed machines to unjam themselves. Springy molecules allow less exacting mechanical design.
Things are inherently more efficient at smaller scales. For example, a meter-scale robot arm may handle (produce) 1 kg/s with 100 W of friction. Eight half-meter arms (the same mass) could handle 2 kg/s with 200 W of friction at the same speed (twice the operating frequency). But throughput scales linearly with speed, while friction in sliding interfaces scales roughly as the square of the speed. So handling 1 kg/s should require only 50 W. If this is scaled to 100-nm arms, then 10,000 kg/s can be handled with 1000 W of friction.
Subquestion E: Nanotechnology has been the domain of scientists. Engineers have a much faster approach to development. How will this affect progress?
Preliminary answer: We have known that the nanoscale existed since atoms and molecules were discovered. But only recently has it become a realm where we can engineer, rather than merely investigate. Investigation requires science, slow and careful experiment punctuated by unpredictable insight. Engineering uses known rules to achieve predictable results.
We now know enough of the nanoscale to predict, with the help of modeling software, what a particular molecule or system will do. This knowledge is imperfect, but sufficient to guide design. We also know some basic rule sets that appear sufficient to design systems for a desired purpose. A novel protein fold has been designed and tested. Many engineered shapes have been made with DNA. Although we don't know nearly all there is to know about the nanoscale, we can design shapes and interactions in a few key domains.
Scientists focus on what we don't know. Engineers focus on what we do know, and what can be done with it. Nanoscale engineering, now that we know enough to do it, will go much faster than scientists would estimate.
Provisional conclusion: The importance of molecular manufacturing is likely to be substantially underestimated by any particular body. However, it is not hard to realize its importance, and the relevant information and theory have been available for many years. If one group comprehends the implications of the theory while others ignore it, then that group may go ahead and develop the technology while others are not even looking. This could lead to unpleasant surprises.
CRN's initial basic findings (preliminary answers and provisional conclusions) for all thirty studies should be verified as rapidly as possible. Because our understanding points to a crisis, a parallel process of conducting the studies is strongly preferred.
We are actively looking for researchers who have an interest in performing or assisting with this work. Please contact CRN Research Director Chris Phoenix if you would like more information or if you have comments on the proposed studies.