Coming clean about that spin

Undergraduate textbooks in quantum mechanics have a long evolutionary cycle. Many books still follow classic texts such as Schiff's Quantum Mechanics , their scope essentially being quantum theory as it had been developed by the 1930s. The format of the traditional text is to build up the theory as a compendium of techniques, thorny issues of interpretation being relegated to often inadequate discussions of the uncertainty principle. This has always seemed odd, as foundational questions are part of the allure of the subject and feature as the public face of quantum theory.

A welcome development in recent textbooks is a more upfront discussion of interpretational issues, such as nonlocality and the measurement problem. B. H. Bransden and C. J. Joachain's text, which aims to provide a self-contained undergraduate course, falls into this category. All the usual topics, such as tunnelling, scattering, and spin, are treated in detail. In this second edition, the authors include recent accessible advances that illustrate the basic principles, such as atom interferometry, Berry's phase and Bose-Einstein condensation. A new chapter on relativistic quantum mechanics is welcome but is somewhat standard fare.

The presentation is clear throughout but one area where the book seems a bit cavalier is the treatment of the classical limit. The conceptual and technical subtleties of this problem can be presented at textbook level, and it is a pity that they have not been openly addressed - if nothing else, they serve as an illustration of the many fascinating unsolved problems in quantum mechanics.

I would not use this book in preference to texts such as Schiff's, but would certainly refer to it as a valuable source of contemporary applications.

Peter Holland is professor in the foundations of physical sciences, University of the West of England, Bristol.