Einstein’s Generation: The Origins of the Relativity Revolution (review)

The title of this book involves a well-chosen pun. In displacing Einstein from the center of a familiar narrative about the relativity “revolution,” Einstein’s Generation brings to our attention the network of contemporary theorists, experimentalists, and instrument makers who were involved in what the author terms “relativity physics” (in distinction from a more narrowly conceived relativity theory). Unsurprisingly, given both the number of people involved and the diversity of their training, that brand of physics was multifaceted. The first few years after the publication of Albert Einstein’s 1905 paper witnessed many relativities; the second meaning of “generation” emerges as Staley tracks the means by which a singular narrative about the content and history of relativity was created through a collective disciplinary engagement that increasingly cast Einstein as the sole creator of a revolutionary theory.

Einstein is rarely mentioned in the first half of the text, which is concerned less with either theory or experiment (the staples of much history of modern physics) than with instrumentation. The central character for the first several chapters is Albert Michelson, the first American to win a Nobel Prize for physics and the inventor of the interferometer, an instrument for making precise measurements of both length and velocity. It is Michelson’s failure to detect the effect of the Earth’s motion through a postulated ether, for which he is most famous today; Einstein would eventually make that result central to his own analysis, which jettisoned the ether entirely. Staley, however, avoids a focus on “ether drift” alone, offering a detailed reconstruction of Michelson’s path to the interferometer and the instrument’s later multiple uses within the broad culture of precision that characterized late nineteenth-century American science. It is an elegant irony that Michelson touted the interferometer’s success in determining the length of a standard meter to remarkable precision after Einstein’s paper destroyed the notion of absolute length and time entirely.

Specialists concerned with the history of fin-de-siècle physics will find much of importance in the second half of the book. The significance of experimental work on fast-moving electrons to the development and reception of electrodynamic theory around 1900 has long been noted. The detailed reconstruction of the material culture of such experiments and the “intimate dialogue between experiment and theory” that Staley provides in this section, however, makes a genuinely original contribution to what might be the best-studied topic in the history of modern physics (258). The book provides the most thorough treatment of the relationship between the cultures of experiment, theory, and instrumentation since the publication of Peter Galison’s Image and Logic (Chicago, 1998).

For the nonspecialist reader, later chapters about the uses of history within physics may prove most illuminating. Eschewing the tired critique of the whiggish, teleological histories often written by scientists, Staley’s takes more interest in how history is used to develop scientific content and communal understanding. Looking at the “participant histories” by those who worked in relativity physics after 1905, Einstein’s Generation recovers the function of historical analysis as a means of “articulating, clarifying, and stabilizing” contemporary scientific work rather than merely describing or shaping it after the fact (297).

The book’s penultimate chapter, continuing this theme, examines the creation of the most important mode of periodization for both physicists and historians of physics alike—the distinction between “classical” and “modern” physics. The terms, which were co-constructed, carried the weight of multiple meanings until the Solvay conference in 1911 helped to solidify the particular understanding prevalent today. Such is the thought-provoking conclusion to a book that manages to accomplish the rare feat of combining empirical depth with theoretical bite.