Is mechanosynthesis feasible? The debate continues.

In my post of December 16th, Is mechanosynthesis feasible? The debate moves up a gear, I published a letter from Philip Moriarty, a nanoscientist from Nottingham University, which offered a detailed critique of a scheme for achieving the first steps towards the mechanosynthesis of diamondoid nanostructures, due to Robert Freitas. The Center for Responsible Nanotechnology‘s Chris Phoenix began a correspondence with Philip responding to the critique. Chris Phoenix and Philip Moriarty have given permission for the whole correspondence to be published here. It is released in a mostly unedited form; however the originals contained some quotations from Dr K. Eric Drexler which he did not wish to be published; these have therefore been removed.

The total correspondence is long and detailed, and amounts to 56 pages in total. It’s broken up into three PDF documents:
Part I
Part II
Part III.

I’m going to refrain from adding any comment of my own for the moment, so readers can form their own judgements, though I’ll probably make some observations on the correspondence in a few days time.

The correspondence between Philip Moriarty and Chris Phoenix, for the time being, ends here. However Philip Moriarty has asked me to include this statement, which he has agreed with Robert Freitas:

“Freitas and Moriarty have recently agreed to continue discussions related to the fundamental science underlying mechanosynthesis and the experimental implementation of the process. These discussions will be carried out in a spirit of collaboration rather than as a debate and, therefore, will not be published on the web. In the event that this collaborative effort produces results that impact (either positively or negatively) on the future of mechanosynthesis, those results will be submitted for publication in a peer-reviewed journal.”

Converging technologies in Europe and the USA

Last Thursday saw a meeting in London to introduce to the UK a report that came out last summer on the convergence of nanotechnology, biotechnology, information technology and neuroscience. Converging technologies for a diverse Europe can essentially be thought of as the European answer to the 2002 report from the USA, Converging Technologies for Improving Human Performance. The speaker line-up, besides me, included social scientists, futurologists, an arms control expert and an official from the European Commission. What was striking to me was how much this debate was framed in terms Europe trying to position itself somewhat apart from the USA, though perhaps this isn’t surprising in view of the broader flow of international politics at the moment.

It’s almost a clich?� that public opinion is very different on the two continents, with the USA being much more uninhibited in its welcoming of new technology than the more technophobic Europeans. George Gaskell, a sociologist from the London School of Economics, presented survey data that at first seems to confirm this view. In his 2002 surveys, he found that while 50% of people in the USA were sure that nanotechnology would be positive in its outcome, only 29% of Europeans were so optimistic. But the picture isn’t as simple as it first appears; the figures for the proportion who thought that nanotechnology would make things worse were not actually that different – 4% in the USA compared to 6% in Europe. The Europeans were simply taking the attitude that they didn’t know enough to judge. The absence of any across-the-board distrust of technology is shown by a comparison of attitudes to three key technologies – nuclear energy, computers and information technology and biotechnology. The data showed almost overwhelming opposition to nuclear power, equally overwhelming enthusiasm for computers and communication technology, and a mixed picture for biotech. The key issues for acceptance prove not to be any deep enthusiasm or distrust for technology in general; it’s simply a balance of the benefits and risks together with a judgement on how much the governance and regulation of the technology can be trusted.

Where there is a big difference between Europe and the USA is in the importance of the military in driving research. J?�rgen Altmann, a physicist turned arms-control expert from The University of Dortmund, is very worried about the military applications of nanotechnology, and his worries are nicely summarised in this pdf handout. His view is that the USA is currently undertaking an arms race against itself, wasting resources that could otherwise be used both to boost economic competitiveness and to counter the real threat that both the USA and Europe face by more appropriate and low-tech means. Others, of course, will differ on the nature of the threat and the best way to counter it.

The balance between civil and military research and development was also highlighted by Elie Faroult, from the Research Directorate of the European Commission, who pointed out with some glee that the EU was now considerably ahead of the USA in investment in most civil research, and that this trend is accelerating as the USA squeezes spending on non-military science. For him, this gave Europe the opportunity to develop a distinctive set of research goals which emphasised social coherence and environmental sustainability as well as economic competitiveness. But having taken the obligatory side-swipe at the USA he finished by saying that of course, looking to the future, it wasn’t the USA that Europe was in competition with. The real competitor for both the USA and Europe was China.

Nanomagnetics

Nature has some very elegant and efficient solutions to the problems of making nanoscale structures, exploiting the self-assembling properties of information-containing molecules like proteins to great effect. A very promising approach to nanotechnology is to use what biology gives us to make useful nanoscale products and devices. I spent Monday visiting a nanotechnology company that is doing just that. Nanomagnetics is a Bristol based company (I should disclose an interest here, in that I’ve just been appointed to their Science Advisory Board) which exploits the remarkable self-assembled structure of the iron-storage protein ferritin to make nanoscale magnetic particles with uses in data storage, water purification and medicine.

Ferritin

The illustration shows the ferritin structure; 24 individual identical protein molecules come together to form a hollow spherical shell 12 nm in diameter. The purpose of the molecule is to store iron until it is needed; iron ions enter through the pores and are kept inside the shell – given the tendency of iron to form a highly insoluble oxide, if we didn’t have this mechanism for storing the stuff our insides would literally rust up. Nanomagnetics is able to use the hollow shell that ferritin provides as a nanoscale chemical reactor, producing nanoparticles of magnetic iron oxide or other metals of great uniformity in size, and with a protein coat that both stops them sticking together and makes them biocompatible.

One simple, but rather neat, application of these particles is in water purification, in a process called forward osmosis. If you filled a bag made of a nanoporous membrane with sugar syrup, and immersed the bag in dirty water, water would be pulled through the membrane by the osmotic pressure exerted by the concentrated sugar solution. Microbes and contaminating molecules wouldn’t be able to get through the membrane, if its pores are small enough, and you end up with clean sugar solution. There’s a small company from Oregon, USA, HTI , which has commercialised just such a product. Essentially, it produces something like a sports drink from dirty or brackish water, and as such it’s started to prove its value for the military and in disaster relief situations. But what happens if you want to produce not sugar solution, but clean water? If you replace the sugar by magnetic nanoparticles then you can sweep the particles away with a magnetic field and then use them again to produce another batch of water, producing clean water from simple equipment with only a small cost in energy.

The illustration of ferritin is taken from the Protein Database’s Molecule of the Month feature. The drawing is by David S. Goodsell, based on the structure determined by Lawson et al., Nature 349 pp. 541 (1991).

Competitive Consumption

Partisans of molecular nanotechnology keep coming back to the theme of the devastation that they say will be caused to the world’s economic systems when it becomes possible to manufacture anything at no cost. Surely, they say, when goods cost nothing to make, then the money economy must wither away? I don’t accept the premise of this argument, but even if I did I think it is based on a misunderstanding of how economics works. The laws of economics, inasmuch as anything in that discipline can be described as a law, are really observations about human nature, and as such are not likely to be overturned on the basis of a mere technological advance. The key fallacy in this way of thinking is very succinctly put in an excellent book I’ve just finished: A nation of rebels: why counterculture became consumer culture, by Joseph Heath and Andrew Potter.

This book is mainly an entertaining polemic against the counterculture and the anti-globalisation movement. What’s relevant to us here is its gleeful demolition of the idea of postscarcity economics, as proposed by Herbert Marcuse and Murray Bookchin. This is the idea that once machines were able to take care of all our material needs and wants, we would be able to form a society based not on the demands of economic production, but on fellowship and love. It’s very easy to see the connection between this and the arguments made by the proponents of molecular nanotechnology.

The key concept in understanding what’s wrong with these ideas is the notion of a “positional good”. Positional goods get their value from the fact that not everyone can have them; people pay lots of money for an expensive and rare sports car like an Aston Martin, not simply because it is a nice piece of engineering, but explicitly because possession of one signals, in the view of the purchaser, something about their exalted status in society. The whole aim of much advertising and brand building is to increase the value of artefacts which often cost very little to make, by associating them with status messages of this kind. Very few people are immune to this, unless they live in cabins in the wilderness; for most of the middle class majorities of rich countries their biggest expenditure is on a house to live in, which by virtue of the importance of location and neighbourhood is an archetypal positional good.

When one realises how important positional goods are in market economies, the fallacy of the idea that molecular manufacturing would cause the end of the money economy becomes clear. In the words of Heath and Potter:

“What eventually led to the undoing of these views was the failure to appreciate the competitive nature of our consumption and the significance of positional goods. Houses in good neighborhoods, tasteful furniture, fast cars, stylish restaurant and cool clothes are all intrinsically scarce. We cannot manufacture more of them, because their value is based on the distinction they provide to consumers. The idea of overcoming scarcity through increased production is incoherent; in our society, scarcity is a social, not a material, phenomenon.”

Trust

I’m grateful to Tim Harper for some kind words about me in his column on nanotechweb.org. Giving his roundup of how nanotechnology fared last year, he notes that 2004 ” was also the year that the tricky issue of the Drexlerian idea of molecular manufacturing – the version popularised by the Foresight Institute – finally began to be addressed in a scientific manner”, and he mentions both this blog and my book Soft Machines in connection with this. But, as he goes on to say, “there is much work to be done, however, to build trust between the scientific and molecular nanotechnology communities”.

To build trust, you need understanding. It’s probably true that many in the scientific community have not made the effort to understand the point of view of the molecular nanotechnology community. But equally, I think that in that community that there is a very widespread lack of understanding about how science works. I don’t mean this in the sense that they don’t understand the scientific method or basic scientific results; it’s the sociological aspects of science as a human enterprise I’m talking about here. You need an understanding of how science as a collective effort selects problems and makes progress in order to be able to predict and understand the ways in which nanoscience will turn into nanotechnology.

A simple example of the sort of misconception that results is the widespread view in the molecular nanotechnology community that the high profile scepticism of figures like Richard Smalley is all that stands in the way of progress towards their goal, because scientists are discouraged from pursuing these lines of enquiry for fear of their career. The truth is absolutely the opposite; there would be no surer way for a young scientist to become rich and famous than by proving Smalley wrong, and you can be confident that if someone with the right experience and the right equipment could think of a way of making a big step towards demonstrating mechanosynthesis, they would be doing it now. And if they were successful, they’d probably find space for a few kind words about Drexler in the speech they gave as they accepted their Nobel prize…

Nanotechnology and universal surveillance

What potential impact of nanotechnology on society should we worry about most? The headlines are being made by the possibility that nanoparticles are especially toxic. This is a real concern, but the problem is relatively bounded and the solutions aren’t difficult to put in place (even if those solutions are going to be bad news for laboratory rats). The primal fear is of loss of control of a technology so powerful that it could lead to the extinction of all life – the problem of grey goo. But as the hubris and lack of realism implicit in the assumption that we will, any time soon, be able to engineer what amounts to a new and superior form of life becomes more apparent, this fear should lose its force.

My major worry is in the way we’ll deal with a world in which computing and communication power is so cheap that every object and artefact can have the capability to sense its environment and interact with its neighbours. RFID and smart dust give us a good idea of which way this technology is heading, and developments in evolutionary nanotechnology are sure both to greatly increase the capability and dramatically decrease the cost of such devices.

Worries about the way this is heading are eloquently stated in an interesting new essay on nanotechnology by one of the grandest figures of US academic nanoscience, George Whitesides (the essay is in the current edition of the new Wiley nanotechnology journal, Small, but it probably needs a subscription for full text access).

“In my opinion, the most serious risk of nanotechnology comes, not from hypothetical revolutionary materials or systems, but from the uses of evolutionary nanotechnologies that are already developing rapidly ….
���Universal surveillance������the observation of everyone and everything, in real time, everywhere; a concept suggested by those most concerned with terrorism���is not a technology that I would wish to see cloak a free society, no matter how protectively intended.”

Availability of Soft Machines

Anyone who has tried to buy a copy of my book Soft Machines: Nanotechnology and Life in the last few weeks will notice that there have been problems of availability – higher demand from the USA than the publisher anticipated has resulted in stocks being cleared out. My publisher now tells me that new stock has just arrived from the printer at the UK warehouse, so within a few days the book should be easier to get hold of.

Nanotechnology films from the European Union

A couple of 1/2 hour documentaries about nanotechnology, made by the EU nanotechnology program, are now available online.

Nano: the next dimension is a serious and straightforward documentary, introduced by the French Nobel Laureate chemist Jean-Maire Lehn, and featuring other eminent European nanoscientists such as Cees Dekker, Harry Kroto and Christian Joachim.

Nanotechnology is aimed at the younger audience. It has does have some good things, despite its rather cheesy attempts to connect with youth culture, and (in the English version) terrible dubbing. It does, however, feature a very silly animation of a medical nanobot.

My thanks to Raymond Monk from the European Commission for bringing this to my attention.

You can’t always get what you want

New readers of the more visionary writings on advanced nanotechnology could be forgiven for thinking that it’s the desires of the writers that come first. They want the material lifestyle of a billionaire, they want to travel in space, they want to live for ever – and advanced nanotechnology is invoked as a Deus ex Machina to make their wishes come true. Scientists are taught not to covet their own hypotheses – not to want to believe in their own theories so deeply that their critical judgement is clouded. This is a good principle, though one that’s difficult for fallible humans always to follow. Science has delivered huge improvements to the human condition, and nanotechnology has the potential to improve things much more. But, difficult as it is, we need to focus not on what we want, but what we can achieve, given the constraints of the universe we live in.

In the words of Sir Michael Jagger,
“You can’t always get what you want
But if you try sometimes you just might find
You get what you need”.

With thanks to David Bott, and a Happy New Year to all my readers.

Molecular nanotechnology, Drexler and Nanosystems – where I stand

For the convenience of new readers of Soft Machines, here’s a quick summary of my personal positions on the question of the feasibility of the variety of nanotechnology proposed by Dr K. Eric Drexler in his book Nanosystems. Many of the arguments are made in my book Soft Machines; I’ve discussed some of these issues in my blog in the last few months, and I’ll get round to going into more detail about some of the others in the New Year.

  • Will it be possible to make functional machines and devices that operate on the level of single molecules?
    Yes. As pointed out by Drexler in his 1986 book Engines of Creation, Nature, in cell biology, gives us many examples of sophisticated machines that operate on the nanoscale to synthesise new molecules with great precision, to process information and to convert energy. We know, therefore, that radical nanotechnology (using this term to distinguish these sorts of fully functional nanoscale devices and machines from the sorts of incremental nanotechnology involved in making nanostructured materials) is possible in principle; the question is how to do it in practise.
  • Do the proposals set out in Drexler’s book Nanosystems offer the only way to achieve such a radical nanotechnology?
    Obviously not, since cell biology constitutes one radical nanotechnology that is quite different in its design principles to the scaled-down mechanical engineering that underlies Drexler’s vision of “molecular nanotechnology”, or MNT. One can imagine an artificial nanotechnology that uses some of the same operating principles and design philosophy as cell biology, but executes them in synthetic materials (as discussed in Soft Machines). Undoubtedly other approaches to radical nanotechnology that have not yet been conceived could work too. In comparing different potential approaches, we need to assess both how easy in practise it is going to be to implement them, and what their ultimate capabilities are likely to be.
  • Does Nanosystems contain obvious errors that can quickly be shown to invalidate it?
    No. It’s a carefully written book that reflects well the state of science in relevant fields at the time of writing. Drexler’s proposals for radical nanotechnology do not obviously break physical laws. There are difficulties, though, of two types. Firstly, in many cases, Drexler used the best tools available at the time of writing, and makes plausible estimates in the face of considerable uncertainty. Since then, though, nanoscale science has considerably advanced and in some places the picture needs to be revised. Secondly, many proposals in Nanosystems are not fully worked out, and many vital components and mechanisms remain at the level of “black boxes”.
  • How easy will it be to implement the vision of diamondoid-based nanotechnology outlined in Nanosystems?
    The Center for Responsible Nanotechnology writes “A fabricator within a decade is plausible – maybe even sooner”. I think this timeline would be highly implausible even if all the underlying science was under control, and all that remained was the development of the technology. But the necessary science is very far from being understood. Firstly, there are important uncertainties about the effect on the proposed mechanisms, based as they are on the scaling down of macroscopic mechanical engineering principles, of ubiquitous features of nanoscale physics such as strong surface forces and Brownian motion. This will be particularly serious for devices intended to work in ambient conditions, rather than at very low temperatures at ultra-high vacuum, and I believe that the problems this will cause are seriously underestimated by proponents of MNT. Secondly, there is currently a huge gap in the implementation pathway. Even proponents of MNT disagree on the best way to reach their goal from our current level of technology. Drexler favours soft and biomimetic approaches (see both Nanosystems, and his letter to Physics World responding to my article), though the means of moving from soft to hard systems remains unclear. Robert Freitas and Ralph Merkle favour a more direct route using diamondoid mechanosynthesis; see the ongoing discussion with Philip Moriarty here for the difficulties that this proposal may face. In conclusion, even if diamondoid-based nanotechnology does not break any physical laws in principle, I believe in practise that it will be very much more difficult to implement than its proponents think.
  • Will the advantages of the diamondoid-based nanotechnology outlined in Nanosystems be so great as to make it worth persisting to overcome these difficulties, whatever the cost?
    This depends what you want to use the technology for. Much of the emphasis from proponents of MNT is on using the technology to manufacture artefacts. But arguably the impacts of nanotechnology will be much more important and far-reaching in areas like information processing, energy storage and transduction, and medicine, where the benefits of diamond as a structural material will be much less relevant. In these areas, evolutionary nanotechnology and other approaches to radical nanotechnology, like soft nanotechnology and bio-nanotechnology, may have a greater impact on a much shorter timescale.
  • If the diamondoid-based nanotechnology proposed in Nanosystems proves to be impossible or impractical to implement, does that mean that nanotechnology will have only marginal impacts on the economy and society?
    Not necessarily. See this post –Even if Drexler is wrong, nanotechnology will have far-reaching impacts – for a discussion.