Last summer, a debate was held at Nottingham in which proponents and sceptics of the Drexlerian vision of molecular nanotechnology exchanged views (with me in the latter camp). I think it was notable both for its constructive tone, and for the high quality of the debate, helped by the presence of many very distinguished UK nanoscientists in the audience. At the time it was promised that a film of the event and a transcript would be published. These things often take longer than expected to come to fruition, but Philip Moriarty now reports, via a comment here, that the transcript, published in the journal Nanotechnology Perceptions, is now available for download from the Nottingham Nanoscience Group’s webpages. Since the links themselves are a bit obscure, the PDF of the transcript is here, and a short introductory piece by Philip is here.
To quote Philip Moriarty’s words: “The transcript on the following pages is the first time that a public (and lengthy) debate on the feasibility of nanomachines and molecular manufacturing, involving a significant number of world-leading surface- and nano-scientists, has been published in its entirety in the scientific literature.”
That sounds like it was a good discussion, although not really a “debate”. I would have liked to see a little more back-and-forth among panel members. You guys did get into it on a couple of questions, and that was the best part IMO.
I thought Philip’s introduction and commentary made good points. His emphasis on researching experimental techniques to demonstrate mechanosynthesis sounds like an excellent path to pursue. Ironically he almost comes off as a supporter of Drexler’s general program, although criticizing excessive enthusiasm on the part of its adherants. In fact, if he or others do succeed in laboratory mechanosynthesis, it will probably be cited by Drexlerians as further evidence for the validity of the molecular manufacturing concept.
Hi Hal,
Umm, I at the meeting and characterising Philip as a ‘supporter’ of Drexlerian Nanotech is way off the mark. Lets just say it was more passionate than that!
The basic outcome of the meeting was that all ideas at this stage are ideas until experimental proof of concept occurs, which has not occured for YET for Drexler’s program for Molecular Manufactoring. That does not mean that some PARTS of Drexler’s program could be incorperated into Mainstream Nanotech like freitas’ program.
Hi Hal and Zelah,
Zelah’s comment is spot-on. (I think that Zelah’s comment re. my support of Drexlerian nanotech. during the debate will be supported when the video is eventually online!). As I mentioned both in the introductory piece I wrote for Nanotechnology Perceptions and during the debate at the core of Drexler et al.’s molecular nanotechnology approach is an exciting idea: computer-controlled chemistry at the single atom/molecule limit. These ideas should be pursued – see below for news on this. That doesn’t, however, mean that I “embrace” the nanofactory concept espoused by Drexler, Phoenix, Burch et al. Nevertheless, I find it a very useful exercise to consider just how one might automate SPM-driven single molecule chemistry and, importantly, move toward the assembly of 3D (rather than 2D) structures. If we could build nanocrystals with molecularly precise volumes (where we can control just how many molecules comprise a nanocrystal) then some fascinating science could be achieved.
During the debate, I found it fascinating – but not wholly unexpected – that the Drexler-Burch nanofactory video, described by, for example, CRN as having the ability to “communicate the potential power of the technology more convincingly than any article or speech” , was attacked on a number of occasions by scientists in the audience as little more than “Hollywood-style pictures”. I don’t believe that this was due to a misunderstanding on the audience’s part: I am fairly confident that they realised the movie was indeed a simulation based on Drexler et al.’s nanoengineering principles, as first laid out in Nanosystems . I would argue that the video damages rather than improves the credibility of the proponents of MNT in, what I’ll call for want of a better term, the mainstream (nano)science community. Why? Because the mainstream nanoscience community has little interest in simulations which have no linkage with the real world via experiment.
A telling exchange during the debate associated with the movie was between Josh Hall and Laurence Eaves (a professor at Nottingham with a vast amount of experience and expertise in the areas of semiconductor physics and the properties of low dimensional systems (quantum dots (i.e. nanoparticles), wells and wires)) and focussed on the underlying physics of the Drexler nanomotor. It is worthwhile noting that there is little more than a few paragraphs on this motor in Nanosystems : yet again, the devil is in the detail. Richard has also pointed this out in a previous post : a detailed design for a nanomotor should be high on the MNT community’s list of priorities.
But…. (and here’s where I suck my teeth just a little), the various debates I’ve had with members of the MNT community (including that with Chris Phoenix at CRN have prompted me to think in quite some detail about strategies for mechanosynthesis (which I certainly see as fundamentally different from the broader area of molecular manufacturing). As a scanning probe microscopist with a keen interest in single atom/molecule manipulation, I see the next logical steps in the field (pioneered by Eigler et al) as:
(i) gaining precise control over the tip chemistry and structure so that specific reactions are possible – Wilson Ho et al and the Rieder group in Berlin have already made stpes in the direction via, for example “CO”-functionalisation of a tip;
(ii) increasing the degrees of freedom possible in single molecule positioning (e.g. having sample rotation and tilt available during manipulation events);
(iii) moving towards the assembly of 3D structures (…tough…);
(iv) automating the process so that nanostructures may be assembled to a particular blueprint;
Rob Freitas and I are slowly (almost infinitesimally!) reaching the point where we could start to attempt some combined experiment-theory on basic mechanosynthetic reactions. In the meantime, however, there’s an announcement related to the 2006-2007 IDEAS Factory scheme funded by the UK Engineering and Physical Sciences Research Council (EPSRC) which may be of interest to the MNT community (particularly the third topic on the list)…
Best wishes,
Philip
Errata to previous post:
The sentence “As I mentioned both in the introductory piece I wrote for Nanotechnology Perceptions and during the debate at the core…” is missing a comma. It should be: “As I mentioned both in the introductory piece I wrote for Nanotechnology Perceptions and during the debate, at the core…”
More importantly, the link to the EPSRC website in the final paragraph doesn’t seem to work. The link is:
http://www.epsrc.ac.uk/researchfunding/programmes/cross-epsrcactivities/ideasfactory/topics0607.htm .
Apologies.
Philip
I like the idea of building nanocrystals with molecularly precise volumes. Specifically, I think expanding the natural library of higher diamonds (adamantane geometries) will be a useful endeavour. Diamond roxatanes could form the building blocks for a wide variety of products even if no actual MNT is taking place.
I’ve just come across this Finnish paper: http://lanl.arxiv.org/PS_cache/cond-mat/pdf/0010/0010096.pdf
It was penned in 2000 and seems to show a simulation of carbon dimer deposition on a carbon terminated diamond (110) surface. That is, not templating on the usually assumed hydrogen terminated surface geometry.
Intuitively to me depositing di-carbon on a carbon terminated diamond surface would result in only more sp2 bonds being created. But this paper seems to suggest more diamond is the product, though I still have to reread it. Is it possible that the basic mechanosynthetic step can be achieved without the need for hydrogen abstraction?!
Streaming video footage of the debate (via Google Video) is now available here .
Best wishes,
Philip