Too many mysteries to clarify

It is a beautiful spring day in Paris," begins the astronomer Trinh Xuan Thuan, and you sense immediately that he is a romantic and that Axel Reisinger's translation has not lost every trace of the French accent. You already know from the blurb that his books are bestsellers in France. Indeed, French scientists play a considerable part in Thuan's story, though the patriotic bias is no more marked than you would find in an English or American writer; he rightly allows that it was John Michell (1783) who conceived, 13 years before Pierre-Simon Laplace, the idea of a black hole too massive for light to escape. I confess, however, to being irked by the romanticism - the rather too frequent references to the beauties of landscape and flowers, the joys of living that we owe to the kindly provisions of nature: "Chaos has been instrumental in liberating Nature. It has given her the freedom to exercise her creativity"; "That is the most efficient solution Nature could find..."; "Why did Nature bother to invent neutrons?" "When (Nature) made the stars she evidently attached great importance..." These are a few of the many examples in the book, except for the last, which is from Stars and Atoms , to show that even Eddington on this one occasion succumbed to the lure of personification.

Eddington was not the only eminent scientist in the past to have excelled in popular exposition; he and Jeans ( The Universe around Us ), Faraday ( The Chemical History of a Candle ) and Boys ( Soap Bubbles ) all succeeded by selecting limited topics to illustrate the methods and results of science. They make the gist of an argument clear while not clogging it with details; above all, they tell nothing that must be unlearned in deeper study. Long after them comes Thuan, with much more material available and a higher ambition to explore as much as he can - but unfortunately too little skill to carry it all off. Perhaps no one could.

There are many good passages, especially on the origin of the solar system, but where the going gets tough, as with general relativity or quantum mechanics, the simplifications are often obscure or positively misleading. In two short paragraphs we learn that "space is curved by gravity", but the mystery remains unresolved, though we are assured that Albert Einstein's inspiration was one of the most marvellous achievements of the human intellect. Again, there is more irritation than instruction in the pages devoted to the author's friends, Jules and Jim, or Emily and Claire, as they suffer time dilatation or the perils of black holes. Fairy-tale science such as this was indulged in for fun by George Gamow ( Mr Tomkins in Wonderland ), but it imparts no significant information and takes too long about it. As a last example, the problem of wave-particle duality in quantum mechanics, the theme of 75 years of philosophical wrangling, is hardly clarified in a discussion of the two-slit experiment by saying that the electrons "may have left the electron gun as particles, but they have turned to waves before reaching the slits". As the duke of Wellington said:

"If you believe that, you will believe anything."

In his foreword, Thuan promises to tell how the sterile deterministic world of 19th-century science was swept away by a far more liberating view in the 20th century, reductionism giving way to holism. He includes among the liberating views the uncertainty principle of quantum mechanics and the more recent explorations of chaos, confusing the former's indeterminism and the latter's strictly deterministic origins. Moreover, he seems to overlook that 19th-century reductionism underpinned a scientifically respectable brand of holism; those old pioneers always kept the complete picture in view as they sought the irreducible elements of its structure. The statistical mechanics of Maxwell and Boltzmann lies closer to the whole world of experience than do the quarks and multidimensional strings of our supreme modern reductionists. Well read as Thuan may be in modern physics and astronomy, he is less happy in history and seems to trust run-of-the-mill textbooks more than historians of science. For example, Max Planck did not postulate the quantisation of light as photons and for years disapproved of Einstein's doing so; nor did he invent his radiation formula to eliminate Rayleigh's ultraviolet catastrophe, of which, at the time, he was unaware.

There are so few good non-technical books about modern physics that I am sorry not to recommend this too-ambitious attempt; it would have been much better if it had attempted less.

Sir Brian Pippard is emeritus professor of physics, University of Cambridge.