by Martinus Veltman, World Scientific. Hardback ISBN 9812381481, £33 ($48). Paperback ISBN 981238149X, £13 ($19).
I greatly enjoyed finally reading a book that goes into the details I always wanted. Not being a physicist myself, I have often attempted, in vain, to find a reasonably deep explanation of the current state of physics. Most books simply re-hash what the curious layperson already knows: relativity and quantum mechanics are weird, there are quarks in everything. They stop short of telling you how and why nature is strange. Veltman, however, has the courage to try a deeper level about what we understand and what is simply fact. He stubbornly and rightfully sticks to what has been experimentally verified. In his words: “space-time and the laws of quantum mechanics are like the decor, the setting of a play. The elementary particles are the actors, and physics is what they do. A door we see on stage is not a door until we see an actor go through it. Else it might be fake, just painted on.” For that reason, you should not expect anything on string theory or supersymmetry. Veltman ends his book with the remark “they are [so far] figments of the theoretical mind.” They are doors we have not seen used.
The narrative of the book suffers from bad English in many places, with irritating errors like “than” instead of “then” and awkward phrasing. There are some paragraph breaks missing and other indications of the impatience of the author. An attempt at explaining how “quadratic implies approximately doubling for percentage increases” completely fails, even though I do understand it.
More worrying are places where Veltman may confuse the reader by omitting forward references. On page 69 we are told that there are three quark colours and three anti-colours. That should make for nine corresponding gluons, which I immediately pictured in a square matrix of nine cells, but then he puzzles me by stating that “the white one” does not exist. On page 77 I find a reference to “diagonal gluons” (ah, my mental picture of the gluon matrix was perhaps not entirely wrong!), but it is only on page 114 that the white gluons are explained through mixing. My copy is now full of notes such as “see also page n”.
However, the amount explained in this book is truly impressive. To show how much effort went into discovering how nature works at the fundamental level, Veltman gives short biographical notes from a number of scientists. They appear in interesting vignettes, printed in a different colour, each on a full page. There are no fewer than 86 names. Veltman has a nice way of setting the historical record straight, tells amusing stories of his encounters with the personalities involved, and makes you smile at the vignette about Ernest Stückelberg.
Even if you have read books popularizing physics before, you have to read this one slowly. There is some maths (fortunately!), but nothing beyond high-school level, and there are many precise colour diagrams. Veltman often repeats what he explained before, and actually dares to say “forget about it” or “that’s the way it is”. This is refreshing as other accounts of physics are always vague about what can be explained in terms of more detailed theory and what we should accept as fact.
I have still not understood spin and attractive forces, but one should leave room for the second edition.
