In April 1943, a young physicist named Robert Serber stood up before a small group of fellow scientists in a laboratory in Los Alamos, New Mexico, and, as one attendee later recalled, began to speak in "a hazy, uncertain voice" about the project on which they would all be working. "The object," he said, "is to produce a practical military weapon
in the form of a bomb in which the energy is released by a fast neutron chain reaction in one or more of the materials known to show nuclear fission." That mechanism, of course, was the atomic bomb, which a little more than two years later would be used against Japan.
In the following weeks, Serber touched on many themes, racing to an array of chalkboards to scribble complex formulas and equations. Among other things, he addressed how big a bomb would need to be in order to achieve critical mass--between 13.5 centimeters and 9 centimeters, he calculated--and what the probability of premature detonation might be. (It was, he concluded, always a danger.) At the end of the series, his lecture notes, classified as top secret, were gathered and printed for distribution to later cadres of scientists who came to work at Los Alamos. Years after the war they were declassified, and Serber, who died in May of 1997, took the opportunity to reflect on his work and the strange culture of the laboratory, adding postscripts and other commentary reproduced in the present edition.
Serber's book is an important document in the history of science, and remains one of the most accessible introductions to nuclear physics ever written. (On that note, those who worry that it is all too easy to find bomb-building instructions in the library or on the Web should rest assured: these lectures were tough for the greatest theoretical physicists of the time to follow.) It all makes for provocative reading. --Gregory McNamee
From the Back Cover
In April 1943, at a new secret laboratory on a mesa in the high New Mexican desert, a crowd of the most brilliant young scientists in America heard five stunning lectures that summed up everything the world knew about how to build an atomic bomb. The lecturer was Robert Serber, a theoretical physicist and protege of J. Robert Oppenheimer; the laboratory was Los Alamos. Serber's lectures, assembled in note form and mimeographed, became the legendary LA-1, the Los Alamos Primer, the first document passed out to new recruits to the wartime enterprise, classified Secret Limited for twenty years after the Second World War and published here for the first time. Now contemporary readers can see just how much was known and how much remained to be learned when the Manhattan Project began. Would the "gadget", the atomic bomb, really work? How powerful would it be? Could it be made small enough and light enough to carry in a bomber? Could its explosive nuclear reaction be controlled? Working with Richard Rhodes, Pulitzer Prize-winning historian of the development of the atomic bomb, Professor Serber has annotated the Primer for the nonscientist. His preface, a lively informal memoir, vividly conveys the mingled excitement, uncertainty, and intensity the Manhattan Project scientists felt. Rhodes's introduction reviews the development of nuclear physics up to the day that Serber stood before his blackboard at Los Alamos and summarizes the work that followed. In this first published edition, the Los Alamos Primer finally emerges from the archives. No lectures anywhere have had greater historical consequences.