author : Richard A. L. Jones

Ever since Drexler, there has been a lot of interest in nanotechnology: manipulation and manufacture of matter at the molecular scale. Here Jones gives an in-depth account of the physics, chemistry, and technologies relevant to such a scale, and paints a rather different picture from the "classical" nanotech view.

The main message is that not only is there plenty of room at the bottom, but also that it's weird down there. Our conventional everyday physical intuitions don't hold. We can't just take classical manufacturing ideas and scale them down in size by many orders of magnitude. The two major difference are brownian motion and strong surface forces (stickiness). Brownian motion -- eternal thermal jostling -- affects the structures (everything jiggles, molecules bend and are soft), and strong surface forces affect composition -- things stick together extremely readily, as if everything is coated with superglue. Think of building during an earthquake with tissue paper soaked in treacle, rather than with lego bricks in a nice stable factory. So much for diamondoid.

But even if Jones isn't convinced by "hard" nanotech, he's convinced that "soft machines" are possible, plausible, and on their way. We just need a soft and probabilistic molecular manufacture, rather than a scaled down version of macro-scale manufacture. We know that this is possible: this is the way biological assembly works. Biology relies on self-assembly. (A system can self-assemble if all the information necessary for its assembly is contained within the system, for example, in the shapes or affinities of molecules. This contrasts with assembly that requires information from outside the system, which can be used for such things as separating out different molecules into different compartments.)

And there is more weirdness. Polymers (long chain molecules) can have bizarre properties, not just the relatively simple properties of wood and metal that we are used to in our macro-scale lives. They can be anisotropic, have different flow properties under different stresses, have other strange mechanical properties, change their sizes, solubilities, and conductivities, and more. This matter isn't just soft, it's fluid, flexible, and smart. The engineering possibilities are mind-boggling, and extremely counter-intuitive (counter macroscopic intuition, that is).

The book reads well, apart from some slightly poor editing that has allowed grammatical errors and infelicities to creep in. However, the concepts in the book are deep enough, broad enough, and crisply explained, that these problems can be shrugged aside as a minor annoyance. Although it reads well, it is not by any means easy read (I've been reading it slowly over the last few months, between other, lighter, stuff), because of that depth and breadth, but it is a fascinating read, essential for all interested in nanotechnology, and what the possibilities are.