Between the wars, a big bang
A study of an amazing era of progress is as lively as the minds behind it, says Robert Lambourne
The Age of Innocence: Nuclear Physics between the First and Second World Wars By Roger H. Stuewer Oxford University Press, 512pp, £39.99 ISBN 9780198827870 Published 26 August 2018
Don’t be put off by the uninformative main title of this book (even the subtitle fails to reveal its full range). It’s a wonderful book. Histories of science often claim to show the way that science is “really” done. This one manages better than most by recognising that there are many ways, and they generally depend on the individuals involved as well as their institutional, cultural and political settings. No mere retelling of scientific events, this is a work in which the effects of antisemitism, hyperinflation and migration sit alongside those of scientific genius.
The book is well written, brilliantly structured and skilfully paced. It is also richly illustrated, with carefully selected photos and a few crucial diagrams. Although deeply scholarly, its virtues make it lively and approachable. It deserves to be enjoyed by a wide audience.
The 21 years separating the end of the Great War from the start of the Second World War were a period of remarkable progress in nuclear physics. The discovery of the tiny, dense nucleus and the appreciation of its central role in every atom were earlier achievements: their chief architect, New Zealander Ernest Rutherford, had already been awarded a Nobel prize and a knighthood. One of the other pioneers, Polish-born Marie Curie, had shared two Nobel prizes and been given her own research institute. The next step for them and their successors was the detailed investigation of the composition and internal structure of the nucleus, and the related study of nuclear decay and reactions that would reveal the forces responsible for radioactivity.
The period began with Rutherford’s announcement of the first artificially induced transmutation of elements. It ended with the unexpected discovery of nuclear fission, a new kind of nuclear decay so powerful that it would enable those who commanded it to decisively end one war, and to dream, for a while at least, of ending all wars.
The combination of experimental findings, theoretical insights and technological developments that filled those years was extraordinary. It included the discovery of the basic nuclear constituents (the proton and the neutron), the realisation that nuclear decay was an inherently quantum phenomenon beyond classical understanding, and the acceptance that the mass-energy equivalence of Einsteinian relativity allowed nuclei to emit electrons and other particles that they had not previously contained. New tools and techniques were developed. Most dramatically, the increasingly powerful accelerators that first split the nucleus in England were then rapidly improved in the US
– a geographical shift that became increasingly common.
Many new people were also important, among them a second generation of Curies in France. One was Hans Bethe in Germany, author of a three-part review article of such significance that it became known as the Bethe bible, even before he became better known for illuminating the nuclear physics of stars. Another was Italian nuclear newcomer Enrico Fermi, a master of theory and experiment who fundamentally transformed the nature of nuclear physics. Several would become Nobel laureates and many, including Bethe and Fermi, would contribute to the intellectual movement from Europe to the US. Perhaps a true end of innocence, after all.