Steaks and Old Sacks

Cooking Without Food

EVER since reading The War of the Worlds, in which bacteria kill the invading Martian monsters while humans remain helpless, I have been fascinated by the idea that very small entities in very large numbers can perform Herculean tasks. We are hearing of astonishing new feats in nanotechnology - the science of the extremely small. Nano-engineers at the German Institute of Microtechnology in Mainz, have built a two-rotor helicopter weighing less than half a gram that flew more than a centimetre into the air. While the vehicle had no practical use, it shows that it is only a matter of time before manipulations of this kind can be made on the atomic scale. At the root of it will be nanomachines, which will be no more that bacteria-sized devices that will take atoms of different elements and assemble them into molecules, or back again into atoms and then into fresh molecules.

You could make almost anything out of the most unpromising materials so long as the right atoms were present. Imagine a large crew on a long space voyage. What would they eat? They could take along stacks of airline-style packed food, but this could add expensively to the mass and volume of the ship. Instead nanomachines could do their cooking, You would have a machine that looked vaguely like a microwave oven. Into this ``food processor" you would stuff old sacking, rusting screws, gravel and whatever other rubbish was conveniently lying around. The appropriate computer software would get to work, and within a few hours out would come a delicious steak with potatoes and a glass of beer. The sacking might be the most important component. For it turns out that four out of the five main requirements of nutrition - proteins, fats, carbohydrates and vitamins - are made from compounds of carbon. Even the fifth, minerals, depends on carbon for their existence in edible form. Fantasy? Not according to Richard Feynman, arguably the century's greatest physicist after Einstein. In a little-known lecture in 1959, he declared: ``It would be possible for a physicist to synthesise any chemical substance that the chemist writes down. Put the atoms where the chemist says, and you make the substance". Nanotechnology promises to become the most important revolution since electronics. It could terraform Mars in a matter of decades or much more quickly turn a heap of coal into a spacecraft made of diamond - if that would be a good idea. There could of course be a sinister side. Nanomachines could be a tremendous advance in weaponry. Invisible invaders could be sent over a national frontier on a gust of wind, enter peoples' bodies and turn them into slime. Imagine such devices in the hands of a Saddam Hussein. But perhaps, like nuclear weapons, they will not be used for fear of retaliation. At all events, nanomachines may be the single most important tools in space technology. In future, a pessimistic scientific appraisal of how prohibitively expensive and time-consuming doing such-and-such would be that fails to take nanotechnology into account can be dismissed as unimaginative nonsense.