Electrodynamics from Ampère to Einstein

Electrodynamics from Ampère to Einstein , Olivier Darrigol , Oxford U. Press, New York, 2000. $130.00 (532 pp.). ISBN 0-19-850594-9

One might hope that historical scholarship would be cumulative, resulting in progressively richer, more coherent, and more truly informative historical narratives and interpretations. In the real world, however, this ideal seems rarely to be realized; historians spend a lot of time and effort arguing back and forth in a noncumulative manner.

Especially regarding the material covered by Olivier Darrigol’s Electrodynamics from Ampère to Einstein, disputes among historians have often generated more heat than light. This is the case, for example, with such topics of perennial concern as the origin of Michael Faraday’s radical ideas concerning the electromagnetic field, the emergence of James Clerk Maxwell’s signal innovations in electromagnetic theory, and the development of Albert Einstein’s special theory of relativity in the context of electrodynamics.

As concerns these topics and others, Darrigol has managed to get beyond the controversy and the confusion, assembling an interesting, coherent, and convincing narrative. By taking the best from the various scholars who have contributed to the field, by discarding the dross with a minimum of fuss and bother, and by adding his own substantial original research as well as his own synthetic vision, Darrigol has crafted a history of electromagnetic experiment and theory in the 19 th century that represents the best the history-of-physics enterprise has to offer. The account has depth: It is historically and technically detailed and sophisticated. And it has breadth: It covers a vast amount of material, which it sets in broad context. Citations and bibliographies of both primary and secondary historical literature are quite complete.

The book is a big one—over 500 pages—and compendious in its outlook, so it is not easy to summarize its conclusions. Very briefly, with respect to the three perennial issues mentioned, Darrigol’ narrative supports the following positions:

First, contrary to much recent writing in the history of science, Faraday’s turn toward field theory is seen not as the result of some initial theoretical or philosophical orientation rigidly applied in his experimental and theoretical practice, but rather as a result of the interplay of theory and experiment in his work. Faraday’s field theory was thus not “constructed” on the basis of fixed preconceptions, but developed from his interaction with the world.

Second, Maxwell’s achievements are to be understood not as the product of some mysterious intuitive power, inscrutable to ordinary mortals, nor as the accomplishments of a confused pioneer who somehow bumbled his way to insight, but rather as accomplishments that are the result of a historical process involving the following elements: the scientific insights of both Faraday and William Thomson, on which Maxwell built; the methodological traditions of the Universities of Edinburgh and Cambridge, which Maxwell used to advantage; and a lifetime of careful work of Maxwell’s own, involving innovative use of both mathematical formalisms and mechanical models.

Finally, Einstein’s accomplishment in the special theory of relativity is to be seen not as a radical and unprecedented break with the past but as an outgrowth of developments in electrodynamics in the late 19th and early 20th centuries. These developments involved a community of thinkers with much in common, including not only the better-known H. A. Lorentz and Henri Poincaré, but also Max Abraham, Alfred Bucherer, Emil Cohn, and others.

The general conclusion to be drawn from these examples is that innovation in science emerges from a historical process involving both observation and thought and both individual contributions and community interactions. Further, the process of innovation can be described, analyzed, and understood; no recourse is needed to inscrutable intuitions, fortuitous bumbling, or predetermined “constructions” as instruments of historical explanation.

There is much more to Darrigol’s book than the examples discussed above. A full generation intervened between the Faraday-Thomson-Maxwell work and Einstein’s. During this period there was much fruitful work both on the continental approach, emphasizing the charges and currents as the fundamental entities, and on the Maxwellian approach, emphasizing the fields. Finally, in the work of Hermann von Helmholtz, Lorentz, and others, these two approaches were amalgamated, resulting in classical electromagnetic theory as we now know it and in the background for Einstein’s work. For the details, read Darrigol; this is a very rich and complex story, and Darrigol tells it well.

As the author himself is quick to point out, his book is not the last word on the subject. For example, the nuances of the “field theory” versus “action at a distance” dichotomy will bear further discussion. And Darrigol’s provocative assertion that Einstein’s views must now “no longer appear … singular [or] isolated” may require some tempering.

Beyond this, the reader may find word choice sometimes unidiomatic, will often wish that diagrams from primary sources had been redrawn, and may sometimes have trouble seeing the forest for the trees in this compendious work. On the other hand, the reader will come out with a sound understanding, in full and authoritative detail, of the central developments in electromagnetic science from Ampère to Einstein.

Some will read the book through and be richly rewarded; others will dip into the book as needed, and they will be richly rewarded as well. One way or another, every physicist should be a user of this book, if perhaps not a buyer at $130.