Information overload

Chemistry & Industry, 18 December 2000

The bit and the pendulum: from quantum physics to m-theory - the new physics of information
Tom Seigfried
New York: John Wiley & Sons, 2000
Ppvi+281, $27.95/18.50, ISBN 0 47132174 5

Information is everything, as the techies and entrepreneurs making their fortunes in the computer-based new economy keep telling us. With all the current hype about all things dotcom and IT-related, it would be easy to miss the fact that small groups of physicists, working in fields as diverse as black holes and DNA, are telling us the same thing - information is everything. Or, perhaps more accurately, everything is information.

Thanks to the ubiquitous computer, information is the new 'superparadigm' for theorists. Just as Newtonian physics fed off the superparadigm of the clockwork universe, and the steam engine inspired scientists to look at everything in terms of energy, the IT revolution has apparently inspired scientists to see everything in terms of information.

By 'information', physicists don't necessarily mean the mere data or knowledge systems of 'information technology', but a more fundamental yet nebulous property from which all things are made. At its simplest level, the information content of a system - whether electron or galaxy - is the number of bits, or yes/no decisions, which are needed to fully describe that system.

John Wheeler, perhaps the most distinguished evangelist for information theory, coined the phrase 'It from bit' to describe the idea. And if that seems like an absurdly glib phrase for such a potentially revolutionary and counter-intuitive piece of physics, it's worth remembering that Wheeler also coined the phrase 'black hole'.

To quote Wheeler - 'It from bit symbolises the idea that every item of the physical world has at bottom - at a very deep bottom, in most instances - an immaterial source and explanation; that which we call reality arises in the last analysis from the posing of yes-no questions and the registering of equipment-evoked responses; in short, that things physical are information-theoretic in origin.'

It may seem like solipsism for software geeks, but Wheeler and others argue that this strange state is an inevitable consequence of the now-familiar oddities of quantum mechanics. At its fundamental level, reality is fuzzy, its exact nature undetermined until observed - a concept most famously explicated by Schrodinger and his cat.

Wheeler again: 'No element in the description of physics shows itself as closer to primordial than the elementary quantum phenomenon, that is, the elementary device-intermediated act of posing a yes/no question and eliciting an answer. Otherwise stated, every physical quantity, every it, derives its ultimate significance from bits.'

So far, so much physics. But the information superparadigm can also be applied to many other fields of science, from neuroscience to m-theory (the latest variant of superstring theory where the ultimate building blocks of existence are two-dimensional membranes rather than one-dimensional strings).

For US mathematician turned molecular biochemist Leonard Adleman, DNA thus becomes an information-processing computer. When the double helix splits to reproduce, the master enzyme slides down a strand, 'reading' the bases and 'writing' their partners - adenine to thymine, and guanine to cytosine.

The realisation led Adleman to develop a prototype DNA computer, first demonstrated in 1994. DNA computers now hold the promise of vast processing power in a test tube - it is admittedly a distant promise, but may yet prove to be a real triumph of information thinking.

Biological cells, meanwhile, are 'information processors extraordinaire' and, according to Princeton ecologist Laura Landweber, biology itself is a computation where DNA is broken up, transmitted and reassembled like email over the internet. It's a powerful analogy, but one is left wondering if it is anything else.

That sense of 'Yes, but so what?' is one that unfortunately recurs throughout 'The bit and the pendulum'. Tom Siegfried, an award-winning science writer on a Texan daily newspaper, presents an entertaining but ultimately frustrating scamper over a rather undefined subject.

The book is a decent enough introduction to some broad concepts of current thought, but does lacks coherence. It's often difficult to know if or how each new subject fits into the overall argument, or whether it's just another random application of the information superparadigm (Siegried claims the coining of that word, by the way, and he's welcome to it).

Siegfried writes in a slightly folksy journalistic style that ensures a relatively easy read by religiously avoiding anything beyond the bare bones of theory, Scientifically minded readers will find their appetite for the meat of the subject unfulfilled, although Siegfried does provide a fair reading list for each chapter.

Anything approaching mathematics is swerved around with a 'You don't want to try this at home' comment that, for this reader at least, rapidly became irritating. It does seem the style, particularly with US pop-science books of this kind, to adopt a joshing tone throughout (the punning title of this volume is perhaps the best indicator of how far from Poe-faced it is), but it does make me wonder who the book is aimed at.

The reader with any scientific knowledge beyond the basic will soon become frustrated at the lack of detail, while a reader with any less would, I would perhaps arrogantly assume, find the whole subject to be rather more information than he would care to deal with.