The Quantum Universe: Everything That Can Happen Does Happen

Brian Cox is now the Tom Cruise of British physics. Even the name of the University of Manchester professor can launch multimillion-dollar media projects, even when he's talking about material that BBC producers have regarded - until not so long ago - as a complete no-no. He has the confidence and charm to make the dullest subject sparkle and shine. Better still, the camera loves him.

Screen success has made Cox a best-selling author. Not long ago, he and his Manchester colleague Jeff Forshaw wrote a short book on Einstein's special theory of relativity, Why Does E=mc²?, whose sales skyrocketed after the first Wonders of the Solar System TV series. Now the duo is back with another co-written short introduction, this time to quantum theory. There have been hundreds of popular books on this subject and most of them have sold in modest numbers, but Cox's popularity guarantees that this one will fly out of the bookstores. To make quite sure, the publishers have backed it with a powerful marketing campaign, aimed at the mass market. Thousands of Cox fans may well end up with The Quantum Universe in their Christmas stocking. What will they find?

Well, there is no doubt about the book's ambition. The authors introduce the basic ideas of quantum mechanics from the beginning and explain several of the most familiar applications, from the way transistors work to the death throes of stars. For good measure, there's a crash course in applying quantum ideas to the subatomic particles produced at Cern's Large Hadron Collider. All this in 242 pages of text.

It would have been quite a ride even if Cox and Forshaw had played it safe and used the orthodox presentation of the theory, but they take a much tougher road. They base their treatment on what experts call the path-integral formalism, ascribed by Cox and Forshaw largely to the late US physicist Richard Feynman. He would certainly have been embarrassed by the credit he is given here - in the early 1950s, when colleagues were showering him with praise for what they believed to be his innovation, he often told his colleague Freeman Dyson: "I don't know what all the fuss is about - [Paul] Dirac did it all before me."

The Quantum Universe is not an easy read. Other authors have attempted to write about this version of the theory, but no one has been as brave as Cox and Forshaw in trying to explain it in detail. They cleverly develop teaching ideas pioneered by Feynman himself in his brief classic, QED: The Strange Theory of Light and Matter, and go some way further.

The result is a book that most obviously appeals to exceptionally bright A-level physics students eager to catch a glimpse of the ideas they might study at university. Even these readers will, however, find this account of quantum theory challenging and occasionally intimidating. The editor - who periodically appears to go AWOL - has allowed much of the book to be written in passive language (sometimes addressed with off-putting stiffness to "the reader") and to feature sentences such as: "We are now going to exploit what we have just learnt." Cox's touch, so light and assured on TV and radio, is rarely in evidence here, except in some heartfelt paeans to the glory of science and a few asides of welcome astringency.

I wonder what the tens of thousands of Wonders of the Solar System viewers will make of all this? Quite a few will, I suspect, feel like the fans of the Tom Cruise of Top Gun who bought the DVD of Eyes Wide Shut. To present quantum mechanics at this level to a mass audience is, I fear, mission impossible.