Monday, May 14, 2007

Prospects for the LHC
[This is my pre-edited Lab Report column for the June issue of Prospect.]

Most scientific instruments are doors to the unknown; that’s been clear ever since Robert Hooke made exquisite drawings of what he saw through his microscope. They are invented not to answer specific questions – what does a flea look like up close? – but for open-ended study of a wide range of problems. This is as true of the mercury thermometer as it is of the Hubble Space Telescope.

But the Large Hadron Collider (LHC), under construction at the European centre for high-energy physics (CERN) in Geneva, is different. Particle physicists rightly argue that, because it will smash subatomic particles into one another with greater energy than ever before, it will open a window on a whole new swathe of reality. But the only use of the LHC that anyone ever hears or cares about is the search for the Higgs boson.

This is pretty much the last missing piece of the so-called Standard Model of fundamental physics: the suite of particles and their interactions that explains all known events in the subatomic world. The Higgs boson is the particle associated with the Higgs field, which pervades all space and, by imposing a ‘drag’ on other particles, gives them their mass. (In the Standard Model all the fields that create forces have associated particles: electromagnetic fields have photons, the strong nuclear force has gluons.)

To make a Higgs boson, you need to release more energy in a particle collision than has so far been possible with existing colliders. But the Tevatron accelerator at Fermilab in Chicago comes close, and could conceivably still glimpse the Higgs before it is shut down in 2009. While no one wants to admit that this is a race, that can’t be doubted – and Fermilab would love to spot the Higgs first.

Which makes it all the more awkward that components supplied by Fermilab for the LHC have proven to be faulty – most recently, a huge magnet that shifted and ruptured a pipe. Fermilab admits to embarrassment at the ‘oversight’, but it has set the rumour mills grinding. For this and (primarily) other reasons, the LHC now seems unlikely to make its first test run at the end of this year. Among other things, it needs to be refrigerated to close to absolute zero, which can’t be done in a hurry.

Extravagant promises can only be sustained for so long without delivery, and so the delays could test public sympathy, which has so far been very indulgent of the LHC. As a multi-million instrument that has only one really big question in sight, the supercollider is already in a tight spot: everyone thinks they know the answer already (the Higgs exists), and that may yet be confirmed before the LHC comes online. But this is a universal problem for high-energy physics today, where all the major remaining questions demand unearthly energies. There’s a chance that the LHC may turn up some surprises – evidence of extra dimensions, say, or of particles that lie outside the Standard Model. But the immense and expensive technical challenges involved in exploring every theoretical wrinkle means that new ideas cannot be broached idly. And arguably science does not flourish where the agenda must be set by consensus and there is no room left for play.

*****

The idea that the UK has lost a ‘world lead’ in nanotechnology, suggested recently in the Financial Times, begged the question of when the UK ever had it. The headline was sparked by a report released in March by the Council for Science and Technology, a government advisory body. But Mark Welland, a nanotech specialist at Cambridge University and one of the report’s expert contributors, says that wires got crossed: the report’s criticisms were concerned primarily with the social, environmental and ethical aspects of nanotech. These were explored at depth in an earlier review of nanotechnology, the science of the ultrasmall, conducted by the Royal Society and the Royal Academy of Engineering and published in 2004.

That previous report highlighted the potential toxicity of nanoparticles – tiny grains of matter, which are already being used in consumer products – as one of the most pressing concerns, and recommended that the government establish and fund a coherent programme to study it. Welland says that some of those suggestions have been picked up internationally, but “nothing has happened here.” The 2004 report created an opportunity for the UK to lead the field in nano-toxicology, he says, and this is what has now been squandered.

What of the status of UK nanotech more generally? Welland agrees that it has never been impressive. “There’s no joined-up approach, and a lack of focus and cohesion between the research councils. Other European countries have much closer interaction between research and commercial exploitation. And the US and Japan have stuck their necks out a lot further. Here we have just a few pockets of stuff that’s really good.”

The same problems hamstrung the UK’s excellence in semiconductor technology in the 1970s. But there are glimmers of hope: Nokia has just set up its first nanotech research laboratory in Cambridge.

*****

As the zoo of extrasolar planets expands – well over 100 are now known – some oddballs are bound to appear. Few will be odder than HD 149026b, orbiting its star in the Hercules constellation 260 light years away. Its surface temperature of 2050 degC is about as hot as a small star, while it is blacker than charcoal and may glow like a giant ember. Both quirks are unexplained. One possibility is that the pitch-black atmosphere absorbs every watt of starlight and then instantly re-emits it – strange, but feasible. At any rate, the picture of planetary diversity gleaned from our own solar system is starting to look distinctly parochial.

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