Quite apart from the obvious pun, it’s tempting to think of nanoscience as typical small science. Most of the big advances are made by small groups working in universities on research programs devised, not by vast committees, but by the individual professors who write the grant applications. Equipment is often quite cheap, by scientific standards – a state of the art atomic force microscope might cost $200,000, and doesn’t need a great deal of expensive infrastructure to house it. If you have the expertise and the manpower, but not the money, you could build one yourself for perhaps a tenth of this price or less. This is an attractive option for scientists in developing countries, and this is one reason why nanoscience has become such a popular field in countries like India and China. It’s all very different from the huge and expensive multinational collaborations that are necessary for progress in particle physics, where a single experiment may involve hundreds of scientists and hundreds of millions of dollars – the archetype of big science.
Big science does impact on the nanoworld, though. Techniques that use the highly intense beams of x-rays obtained from synchrotron sources like the ESRF at Grenoble, France, and the APS, on the outskirts of Chicago, USA, have been vital in determining the structure, at the atomic level, of the complex and efficient nanomachines of cell biology. Neutron beams, too, are unique probes of the structure and dynamics of nanoscale objects like macromolecules. To get a beam of neutrons intense enough for this kind of structure, you either need a research reactor, like the one at the Institut Laue-Langevin, in Grenoble (at which I am writing this), or a spallation source, such as ISIS, near Oxford in the UK. This latter consists of a high energy synchrotron, of the kind developed for particle physics, which smashes pulses of protons into a heavy metal target, producing showers of neutrons.
Synchrotron and neutron sources are run on a time-sharing basis; individual groups apply for time on a particular instrument, and the best applications are allocated a few days of (rather frenetic) experimentation. So in this sense, even these techniques have the character of small science. But the facilities themselves are expensive – the world’s most advanced spallation source for neutrons, the SNS currently being built in Oak Ridge, TN, USA, will cost more than $1.4 billion, and the Japanese source J-PARC, a few years behind SNS, has a budget of $1.8 billion. With this big money comes real politics. How do you set the priorities for the science that is going to be done, not next year, but in ten years time? Do you emphasise the incremental research that you are certain will produce results, or do you gamble on untested ideas that just might produce a spectacular pay-off? This is the sort of rather difficult and uncomfortable discussion I’ve been involved in for the last couple of days – I’m on the Scientific Council of ILL, which has just been having one of its twice yearly meetings.