Quantenmechanik im Kalten Krieg: David Bohm und Richard Feynman - by Christian Forstner

Abstract

Christian Forstner Quantenmechanik im Kalten Krieg: David Bohm und Richard Feynman ( Stuttgart , GNT-Verlag , 2007 ), 242 pp. , [ hbk ] €30.00 ISBN 978-3-928186-81-0 . This book is about the social context of the development of quantum physics in the Cold War period. It is presented in the form of a comparative socio-biographical study of two American physicists, David Bohm (1917–1993) and Richard Feynman (1918–1988), and their very different careers and approaches and contributions to quantum physics. Bohm is known for his formulation of a new interpretation of quantum mechanics in 1952 invoking so-called ‘hidden parameters'. A year before that, he was suspended from Princeton University because of his involvement with the political Left and took up a position in Brazil. Feynman has often been portrayed, not least by himself, as a completely context-free genius who received the Nobel Prize in 1965 for his contributions to quantum electrodynamics. Forstner offers a fresh view of these theoretical physicists, and what is particularly notable is that not only the ‘outsider’ Bohm but also the ‘genius’ Feynman is placed within a social and ideological context. The book fascinates all the way from its introductory chapter about the emergence of what was (after WWII) called the Copenhagen Interpretation of quantum mechanics and its pragmatic reception in the US (a chapter which perhaps ought to have been called ‘Von Europa nach Amerika’ rather than ‘Von Deutschland nach Amerika’), to the later case studies of Bohm and Feynman and their respective contributions to quantum physics. Unlike the typical numbers-oriented American physicist that focused exclusively on practical calculations, Bohm was preoccupied with the foundations of quantum mechanics and the philosophy of science. Of particular interest is Forstner's analysis of Bohm's early political engagement, his Marxism, and his motivation in dialectical materialism in writing his textbook Quantum Theory (1951) (in which Bohm seems to have been supportive in his own way of the Copenhagen Interpretation), and later in formulating his hidden variables interpretation. In his treatment of Feynman, Forstner analyses and challenges Feynman's self-understanding and demonstrates convincingly that Feynman was not context-free but was driven by an identifiable instrumentalist scientific ideology which, however, contrary to Bohm's, resonated well with the typical American physicist's way of thinking. In his analysis Forstner makes use of Ludwik Fleck's concepts of thought collective and thought style. Hence, the careers of the two main figures and their respective approaches and contributions to quantum physics are understood in relation to their respective local and political thought collectives and thought styles. Through this perspective social aspects of the development of theoretical physics become obvious. However, sometimes the use of Fleck's scheme seems to get in the way of the flow of the narrative, and it fails to bring out perspectives of the story pertaining to individual efforts. For example, Forstner explains the fact that Bohm pursued his ideas about a new interpretation of quantum mechanics by his dismissal from Princeton and his later exile from the US, and hence his isolation from the American physicists' thought collective and style; the reason being that Bohm no longer felt inhibited by the American pragmatic thought style but could pursue his own thinking freely. Framing this work in dialectical materialism could even be taken as suggesting it was means of defiance against his oppressors. Indeed this sounds plausible. However, the discussion with Einstein, who was based at the Institute of Advanced Study in Princeton, about the new interpretation of quantum mechanics, seems also to have been important for Bohm's further pursuit of these ideas, and it would have been interesting if this link had been explored on a deeper level. Moreover, the comparative biographical analysis might have been enriched by a greater attention to personal or psychological traits of the two physicists, such as Feynman's humorous attitude and recklessness versus Bohm's tendency to depression. The book has a clear and well balanced structure and Forstner is lucid in addressing the central issues he wants to highlight in the difficult and complex physics of the two protagonists, employing only a few relevant mathematical formulas. The book is based on a wide variety of sources such as original contributions to quantum electrodynamics and the foundations of quantum mechanics, unpublished manuscripts, private correspondence, oral history, and the FBI files about his two heroes.