Category: General

Reactions to “Rupturing the Nanotech Rapture”

It’s a couple of weeks since my article in the current edition of IEEE Spectrum magazine (the Singularity Special) – “Rupturing the Nanotech Rapture” – appeared, and it’s generated a certain amount of discussion on the nanotech blogs. Dexter Johnson, on Tech Talk (IEEE Spectrum’s own blog) observes that “In all it’s a deftly diplomatic piece, at once dispelling some of the myths surrounding the timeline for molecular nanotechnology contributing to the Singularity while both complementing and urging on the early pioneers of its concept.” I’m very happy with this characterisation.

On Nanodot, the blog of the Foresight Institute, the piece prompts the question: “Which way(s) to advanced nanotechnology?” The answer is diplomatic: “Certainly the “soft machines” approach to nanotechnology holds great promise for the near term, while the diamondoid mechanosynthesis approach is only in the very early stages of computer simulation.” This certainly captures the relatively slow progress to date of diamondoid mechanosynthesis, and attracts the scorn of nanobusinessman Tim Harper, who writes on TNTlog “Perhaps more roadkill than tortoise to nanoscience’s hare is diamondoid mechanosynthesis, beloved of the Drexlerians, which doesn’t seem to have made any progress whatsoever, and increasingly resembles a cross between a south sea cargo cult and Waiting for Godot.”

Over on the Center for Responsible Nanotechnology, the Nanodot piece prompts the question “Which way from here?” (though CRN doesn’t actually mention me or the Spectrum piece directly). The question isn’t answered – “CRN also remains agnostic about whether a top-down or bottom-up angle or a soft/wet or hard/dry approach will be more successful.” This doesn’t seem entirely consistent with their previous published positions but there we are.

The longest response comes from Michael Anissimov’s blog, Accelerating Future. This runs to several pages, and deserves a considered response, which is coming soon.

On expertise

Whose advice should we trust when we need to make judgements about difficult political questions with a technical component? Science sociologists Harry Collins and Robert Evans, of Cardiff University, believe that this question of expertise is the most important issue facing science studies at the moment. I review their book on the subject, Rethinking Expertise, in an article – Spot the physicist – in this month’s Physics World.

Lichfield lecture

Tomorrow I’m giving a public lecture in the Garrick Theatre, Lichfield, under the auspices of the Lichfield Science and Engineering Society. Non-members are welcome.

Lichfield is a small city in the English Midlands; it’s of ancient foundation, but in recent times has been eclipsed by the neighbouring industrial centres of Birmingham and the Black Country. Nonetheless, it should occupy at least an interesting footnote in the history of science and technology. It was the home of Erasmus Darwin, who deserves to be known for more than simply being the grandfather of Charles Darwin. Erasmus Darwin (1731 – 1802) was a doctor and polymath; his own original contributions to science were relatively slight, though his views on evolution prefigured in some ways those of his grandson. But he was at the centre of a remarkable circle of scientists, technologists and industrialists, the Lunar Society, who between them laid many of the foundations of modernity. Their members included the chemist, Joseph Priestly, discoverer of oxygen, Josiah Wedgwood, whose ceramics factory developed many technical innovations, and Matthew Boulton and James Watt, who between them take much of the credit for the widespread industrial use of efficient steam power. In attitude they were non-conformist in religion – Priestley was a devout Unitarian, who combined thoroughgoing materialism with a conviction that the millennium was not far away, but Erasmus Darwin verged close to atheism. Their politics was radical – dangerously so, at a time when the example of the American and French revolutions led to a climate of fear and repression in England.

The painting depicts another travelling science lecturer demonstrating the new technology of the air pump to a society audience in the English Midlands. The painter, Joseph Wright, from Derby, was a friend of Erasmus Darwin, and the full moon visible through the window is probably a reference to the Lunar Society, many of whose members Wright was well acquainted with. Aside from its technical brilliance the painting captures both the conviction of some in those enlightenment times that public experimental demonstrations would provide a basis of agreed truth at a time of political and religious turbulence, and, perhaps, a suggestion that this knowledge was after all not without moral ambiguity.

An experiment on a bird in an air pump
An experiment on a bird in an air pump, by Joseph Wright, 1768. The original is in the National Gallery.

USA lagging Europe in nanotechnology risk research

How much resource is being devoted to assessing the potential risks of the nanotechnologies that are currently at or close to market? Not nearly enough, say campaigning groups, while governments, on the other hand, release impressive sounding figures for their research spend. Most recently, the USA’s National Nanotechnology Initiative has estimated its 2006 spend on nano-safety research as $68 million, which sounds very impressive. However, according to Andrew Maynard, a leading nano-risk researcher based at the Woodrow Wilson Center in Washington DC, we shouldn’t take this figure at face value.

Maynard comments on the figure on the SafeNano blog, referring to an analysis recently done by him and described in a news release from the Woodrow Wilson Center’s Project on Emerging Nanotechnologies. It seems that this figure is obtained by adding up all sorts of basic nanotechnology research, some of which might have only tangential relevance to problems of risk. If one applies a tighter definition of research that is either highly relevant to nanotechnology risk – such as a direct toxicology study – or substantially relevant -such as a study of the fate in the body of medical nanoparticles – it seems that the numbers fall substantially. Only $13 million of the $68 million was highly relevant to nanotechnology risk, with this number increasing to $29 million if the substantially relevant category is included too. This compares unfavourably with European spending, which amounts to $24 million in the highly relevant category alone.

Of course, it isn’t the headline figure that matters; what’s important is whether the research is relevant to the actual and potential risks that are out there. The Project on Emerging Nanotechnologies has done a great service by compiling an international inventory of nanotechnology risk research which allows one to see clearly just what sort of risk research is being funded across the world. It’s clear from this that suggestions that nanotechnology is being commercialised with no risk research at all being done are wide of the mark; what requires further analysis is whether all the right research is being done.

Molecular scale electronics from graphene

The remarkable electronic properties of graphene – single, one-atom thick, sheets of graphite – are highlighted in a paper in this weeks Science magazine, which demonstrates field-effect transistors exploiting quantum dots as small as 10 nm carved out of graphene. The paper is by Manchester University’s Andre Geim, the original discoverer of graphene, together with Kostya Novoselov and other coworkers (only the abstract is available without subscription from the Science website, but the full paper is available from Geim’s website(PDF)).

A quantum dot is simply a nanoscale speck of a conducting or semiconducting material that is small enough that the electrons, behaving as quantum particles, behave in a different way because of the way in which they are confined. What makes graphene different and interesting is the unusual behaviour the electrons show in this material to start with – as explained in this earlier post, electrons in graphene behave as if they were mass-less, ultra-relativistic particles. For relatively large quantum dots (greater than 100 nm), the behaviour is similar to other quantum dot devices; the device behaves like a so-called single electron transistor, in which the conductance of the device shows distinct peaks with voltage, reflecting the fact that current is carried in whole numbers of electrons, a phenomenon called Coulomb blockade. It’s at sizes less than 100 nm that the behaviour becomes really interesting – on these size scales quantum confinement is becoming important, but rather than producing an ordered series of permitted energy states, as one would expect for normal electrons, they see behaviour characteristic of quantum chaos. Pushing the size down even further, the techniques being used give less control over the precise shape of the quantum dots that are made, and their behaviour becomes less predictable and less reproducible. Nonetheless, even down to sizes of a few nanometers, they see the clean switching behaviour that could make these useful electronic devices.

For more context, see this Commentary in Science (subscription required), and this BBC news story.

Graphene based quantum dots (A. Geim, Manchester University)
Left: Scanning electron micrograph of a single-electron transistor based on a graphene quantum dot. Right: Schematic of a hypothetical transistor based on a very small graphene quantum dot. A.K. Geim, University of Manchester, from Science 320 p324 (2008)

Leading nanotechnologist gets top UK defense science job

It was announced yesterday that the new Chief Scientific Advisor to the UK’s Ministry of Defense is to be Professor Mark Welland. Mark Welland is currently Professor of Nanotechnology and the head of Cambridge University’s Nanoscience Centre. He is one of the pioneers of nanotechnology in the UK; he was, I believe, the first person in the country to build a scanning probe microscope. Most recently he has been in the news for his work with the mobile phone company Nokia, who recently unveiled their Morph concept phone at an exhibition at New York’s Museum of Modern Art, Design and the Elastic Mind.

To Canada

I’m off to Canada on Sunday, for a brief canter round Ontario. On Monday I’m in the MaRS centre in Toronto, where I’m speaking about nanotechnology in the UK as part of a meeting aimed at promoting UK-Canada collaboration in nanotechnology. On Tuesday I’m going to the University of Guelph, where I’m giving the Winegard lecture in Soft Matter Physics. On Wednesday and Thursday I’ll be at the University of Waterloo, visiting Jamie Forrest, and McMaster University, to congratulate Kari Dalnoki-Veress on winning the American Physical Society’s Dillon Medal. My thanks to Guelph’s John Dutcher for inviting me.

Which nanotechnology?

It seems likely that nanotechnology will move a little higher up the UK news agenda towards the end of this week – tomorrow sees the launch event for the results of a citizens’ panel run by the consumer group Which?. This will be quite a high profile event, with a keynote speech by the Science Minister, Ian Pearson, outlining current UK nanotechnology policy. This will be the first full statement on nanotechnology at Ministerial level for some time. I’m one the panel responding to the findings, which I will describe tomorrow.

The rain it raineth on the just

I’m optimistic in general about the prospects of solar energy; as should be well known, the total amount of energy arriving at the earth from the sun is orders of magnitude more than is needed to supply all our energy needs. The problem currently is reducing the price and hugely scaling up the production areas of photovoltaics. But, as I live in the not notoriously sunny country of Britain, someone will always want to make some sarcastic comment about how we’d be better off trying to harvest energy from rain rather than sun here. So I was pleased to see, in the midst of a commentary from Philip Ball on the general concept of scavenging energy from the environment, a reference to generating energy from falling raindrops.

The research, described in an article in physorg.com: Rain power: harvesting energy from the sky, was done by Thomas Jager, Romain Guigon, Jean-Jacques Chaillout, and Ghislain Despesse, from Minatec in Grenoble. The original work is described in two articles in the journal Smart Materials and Structures, Harvesting raindrop energy: theory and Harvesting raindrop energy: experimental study (subscription required for full article). The basic idea is very simple; it uses a piezoelectric material, which generates a voltage across its faces when it is deformed, to convert the energy imparted on the impact of a raindrop onto a surface into a pulse of electrical current. The material chosen is a polymer called poly(vinylidene fluoride), which is already extensively exploited for its piezoelectric properties in applications such as microphones and loudspeakers.

So, should we abandon plans to coat our roofs with solar cells and instead invest in rain-energy harvesting panels? It’s worth doing a back of an envelope sum. The article claims that a typical raindrop’s velocity is about 3 m/s. Taking Sheffield’s average annual rainfall of about 80 cm, we can estimate the total kinetic energy of the rain landing on a square meter in a year as 3600 J, corresponding to a power per unit area of about 3 milliwatts. This isn’t very impressive; even at these dismal northern latitudes the sun supplies about 100 W per square meter, averaged over the year. So, even accounting for the fact that PVDF is likely to be a lot cheaper than any photovoltaic material in prospect, and energy conversion efficiencies might be higher, its difficult to see any circumstances in which it would make sense to try and collect rainwater energy rather than sunlight.

UK Government outlines nanorisk research needs

The UK government has released a second report reviewing progress and identifying knowledge gaps about the potential environmental and health risks arising from engineered nanoparticles. This is a comprehensive document, breaking down the problem into five areas. The first of these is the question of how you detect and measure nanoparticles and the second considers the ways in which people and the environment might be exposed to nanoparticles. The third area concerns the assessment of the degree to which some nanoparticles might be toxic to humans, while the fourth area considers potential environmental impacts. Finally, a fifth section considers wider social and economic dimensions of nanotechnology.

The document represents, in part, a response to the very critical verdict on the UK government’s response on nanotoxicology given by the Council for Science and Technology last March. It isn’t, of course, able to address the fundamental criticism: that the Government didn’t act on the recommendation of the Royal Society and set up a coordinated programme of research into the toxicology and health and environmental effects of nanomaterials, with dedicated funding, but instead relied on an ad-hoc process of waiting for proposals to come in through peer review with opportunistic funding from a number of sources. The response from the Royal Society reflects the continuing frustration at opportunities lost: “The Government has recognised the huge potential of nanotechnology and recognised what needs to be done to ensure that advances are realised safely, but by their own admission progress has been slow in some areas. Given the wealth of expertise in UK universities and industries we should be further ahead.”

That’s old ground now, of course, so perhaps it’s worth focusing on some of the positive outcomes reported in the report. Quite a lot of work has been carried out or at least started. In the area of nanoparticles in the environment, for example, the Natural Environment Research Council has funded more than £2.3 million worth of projects, in areas ranging from studies of the toxicity of nanoparticles to fish and other aquatic organisms, to studies of the fate of silicon dioxide nanoparticles from pharmaceutical and cosmetic formulations in wastewaters and of the effect of silver nanoparticles on natural bacterial populations.

For another view of the positives and negatives of this report, it’s interesting to see the response of nanoparticle expert Andrew Maynard. More shocking is the way this report is mendaciously misquoted in an article in the Daily Mail: Alert over the march of the ‘grey goo’ in nanotechnology Frankenfoods (via TNTlog).