American Scientist

The Quantum Beat: The Physical Principles of Atomic Clocks. F. G. Major. 475 pp. Springer-Verlag, 1998. $49.95.

When you're the new kid in a lab, you wish for a book that will bring you up to speed on the background of all that goes on there. Here is a book that provides just that, the essential physics underlying a technology, at a level accessible to a college physics student—and not just for a standards lab, although that is its focus. The author, intimately involved with the subject matter, covers a vast amount of ground broadly definable as applied atomic physics and subsuming laser physics, quantum electronics and some relativity while touching on everything from classical mechanics and statistical mechanics to optics and elementary particles. The melange is a treat. Physics, one learns, is a seamless web.

Moreover, the flow of the book tracks a process of developing a technology, highlights the successful turns taken and does not spare the frustration with funding agencies when support is not forthcoming. There is a vast span of both physics and technology in this tale and a lesson that in solving a class of practical problems, a purview of physics is always helpful. The author enunciates some of the technological challenges of our age and demonstrates how an evolving technology steers a course around the shoals of successive fundamental and technological limits.

A charm of the book lies in the way the author drives home conceptual analogies such as between resonant cavity coupling and spring escapements. It is a shame, though, that the book seems only scantly edited. I found no glaring errors, only unfortunate unevenness that might put a reader off or make the book less useful than it would otherwise be. For example, although some references to historical figures have overlays of anecdotes, sometimes the author doesn't even give a person's first name. "Cady," whose early quartz oscillator patents were challenged in 1918 by "Nicholson," doesn't merit initials in either the index or the text, whereas Nicholson gets his initials in the index but not in the text. The Boltzmann constant is defined and given a value at an unindexed page. The reader also needs to take some gratuitous language in stride: The author talks about the "obvious dependence of the [AC Stark] shift on the intensity of the light" without laying any groundwork against which the dependence might be obvious. And sometimes symbols are used before they are defined or without adequate introduction.

The book is nicely self-contained, starting with only the most elementary assumptions regarding the technical background of the reader. However, an appendix of further reading is not annotated and it is uneven: Some references are tutorial, some archival and some narrative. A few footnotes might also have been helpful. When the day comes for a second edition, the book could be made even more useful by attention to these details.—Samuel J. Petuchowski, Bromberg & Sunstein LLP, Boston