The Quantum Dissidents: Rebuilding the Foundations of Quantum Mechanics (1950–1990), Olival Freire Jr, Springer, 2015. $99.00 (356 pp.). ISBN 978-3-662-44661-4 Buy at Amazon
In September 1967 experimentalist Otto Frisch wrote a letter to his cousin Hugo Tausk, the father of a young physicist named Klaus Tausk. A year earlier Klaus had distributed a preprint of a paper critical of the orthodox, so-called Copenhagen interpretation of quantum mechanics and had ignited a fierce controversy. Frisch made clear in his letter that much more than physics was at stake. The orthodox view, he noted, states that physics is concerned with measurements rather than with objects: “That tastes like idealism, and is therefore rejected by the communists. Vice versa also applies, since anyone here in the West who doubts the orthodox interpretation—even for objective reasons—is suspect[ed] of communism.”
Of course, that binary did not properly hold, Frisch continued, for the debate possessed “the complexities and meaninglessness of a religious war, complete with converts: the greatest defender of the orthodoxy is a communist [Léon Rosenfeld], and many in the opposition are fully bourgeoise.” Despite support from some, the younger Tausk suffered for his apostasy. His adviser refused to attend his thesis defense, and the examiners who did attend almost failed him. His career sputtered in the aftermath of the controversy he had almost inadvertently entered into.
The Tausk controversy and others that concern the foundations of quantum mechanics are the subject of Olival Freire Jr’s exceptionally well-researched book, The Quantum Dissidents: Rebuilding the Foundations of Quantum Mechanics (1950–1990). Freire is one of the world’s leading historians of post–World War II quantum theory. The tale he tells is a fascinating one. In the 1950s the question of the appropriate epistemological and ontological foundations of quantum mechanics was considered settled. That is why Rosenfeld objected to Werner Heisenberg’s introduction around 1955 of the term “Copenhagen interpretation”—it implied the existence of some alternative interpretation. In the 1980s—a time that featured experiments involving tests of Bell’s inequalities—foundational questions were among the most exciting in contemporary physics. The question the book asks is thus straightforward but very important: How did a subject move from the periphery of physics—worthy of contemplation by philosophers, perhaps, but not practicing scientists—into the center?
Freire considers three answers. First, the answer given by those working within the field of quantum foundations today, and also by the late historian Joan Bromberg, points to the availability of the technical means to test assumptions experimentally. Second, the social and cultural contexts in which such work was being done, including—as the Frisch quotation above suggests—Marxism as well as the broader counterculture movement (analyzed in detail by David Kaiser in How the Hippies Saved Physics; W. W. Norton, 2012), helped open the field to questions of many kinds. And third, conceptual currents and problems (discussed by Freire with deftness and precision) helped to produce fertile ground into which eventual technological breakthroughs could plant seeds.
Throughout, Freire argues that those who pushed for heterodoxy should be seen as dissidents. They did not have a common position but rather an antiposition, critical of orthodoxy, and like their opponents, they did not necessarily agree on precisely what the orthodoxy was. Foundational questions, the dissidents believed, were worthy of professional study, and refusing to engage them amounted to dogmatism. Solid histories don’t often have heroes, but it is hard not to be on the side of the dissidents here, particularly when faced with a figure like Rosenfeld, whose hostility and certainty induced nominal ally Wolfgang Pauli to mock him as .
The book is structured chronologically. The first main chapter looks at David Bohm’s hidden-variables theory and situates it both intellectually and politically; the next one examines the “heresy” of Hugh Everett III. Though both scientists inspired considerable controversy, neither managed to alter the “monocracy of the Copenhagen school.” That required the authority of a figure like Eugene Wigner, responsible for what became known as the “Princeton school,” which then vied for orthodoxy against Rosenfeld and his allies.
The rest of the book recounts the Tausk episode; the 1970 Varenna Summer School on the foundations of quantum mechanics, described as “the Woodstock of quantum dissidents”; and key experimental advances from the 1970s onwards, including the aforementioned tests of Bell inequalities. The concluding chapter offers a brief collective biography of the dissidents.
Freire writes in clear and unfussy prose; he is equally adept at explaining the theories of sociologists and physicists. The story, however, is complex. Those not intimately familiar with the material should read each chapter’s introduction and shaded conclusion sections before reading the body text to better orient themselves through what can feel at times like a blizzard of names, affiliations, theories, and experiments. Unfortunately, perhaps because it is itself an overview, the single most complex chapter—on work in the 1980s and early 1990s—lacks a concluding summary.
Even so, The Quantum Dissidents is an impressive book and will be, perhaps ironically, foundational for further studies.
Suman Seth is an associate professor and historian of physics and medicine in the department of science and technology studies at Cornell University. He is the author of Crafting the Quantum: Arnold Sommerfeld and the Practice of Theory, 1890–1926 (MIT Press, 2010).
