David Bohm
A life dedicated to understanding the quantum world
Book proposal
Olival Freire Junior
Research on the foundations of quantum mechanics completely changed status in the
second half of the 20th century. Initially considered a philosophical issue, without much
relevance to science itself, it ended the century as a high profile subject of research
forming the basis of the blossoming research on quantum information. Treating
foundations as just philosophical issues enhanced professional bias against the subject
considered the realm of philosophical research and not research in physics. I have used
the term quantum dissidents to designate the physicists who through their work pushed
this subject from the margins to the mainstream of physics (Freire Junior 2015).
Paramount among these quantum dissidents was David Bohm (1917-1992), the subject
of this proposed biography.
Bohm worked almost entirely dedicated to this subject for more than 40 years.
His most original and heterodox contribution to quantum physics may have been the
elaboration of the causal interpretation of quantum physics, published in 1952 (Bohm
1952), which strongly departed from the standard theory in its conceptual and
philosophical assumptions but still got the same predictions, at least in the
non-relativistic domain. With this Bohm opened the way for alternative interpretations of
quantum mechanics and inspired John Bell to develop, a decade later, what is now
called Bell’s theorem. However, his contribution was poorly received at the time.
than physics. In addition, Bohm hoped to obtain a relativistic generalization of his
causal interpretation, however, failed to do so. His quest for a new interpretation for
quantum mechanics was associated to a disdain of the mathematical machinery –
renormalization techniques - built by Feynman and others to deal with the infinities
plaguing quantum field theories. All this together may have alienated him from the kind
of physics being developed in the 1950s, and led him to a certain isolation among his
fellow physicists. Despite this, he was able to make another contribution to our
understanding of quantum mechanics, which was immediately recognized as a major
breakthrough. Indeed, in the late 1950s, he and Yakir Aharonov published their seminal
paper on the understanding of the role of phases and electromagnetic potentials in the
quantum description of the world (Aharonov and Bohm 1959). Later on, he abandoned
the causal interpretation and moved to the highly mathematical approach called implicit
order. Working with Basil Hiley, he looked for the most basic algebraic structures from
where quantum theory might emerge. In the early 1980s Bohm saw his initial
interpretation revived by some of his students who were able to produce
computer-created graphs of trajectories and potentials obtained from the causal interpretation of
quantum physics (Philippidis, Dewdney et al. 1979). He spent his last years trying to
reconcile his different approaches to the quantum (Bohm and Hiley 1993).
However, Bohm’s contributions to physics were not limited to foundations of
quantum mechanics. He was a doctoral student of Oppenheimer at Berkeley in the early
1940s, and worked for the Manhattan Project. He emerged from the war effort
considered a highly promising American theoretical physicist and was invited to the
elite 1947 Shelter Island conference and then hired by Princeton University. He became
a major protagonist in the field of plasma physics. After working on the problem of
electrical currents passing through a gas in magnetic fields he went on to study plasmas.
When the war ended, Bohm and his graduate students Eugene Gross and David Pines
worked on plasmas, developing the approach called “collective variables” and applied it
to the study of current in metals, elaborating a quantum approach to the phenomenon
using the same collective variable resource he had successfully applied in the classical
treatment of plasmas. Later, this approach was used in nuclear physics by Aage Bohr
and Ben Mottelson. The jointly-authored papers of Bohm, Pine, and Gross became
landmarks in this field. He also wrote a textbook on quantum physics which was well
accepted and is used till today. After the book was published in 1951, he turned to work
Bohm’s achievements in science rank him as a very influential physicist in the
20th century. He was elected Fellow of the Royal Society, had a Festchrift with papers
signed by four Nobel prize winners (Bohm, Hiley et al. 1987), and had his work on the
reinterpretation of quantum mechanics featured in the Physical Review centennial
anniversary volume. Using the metrics of the number of citations, his influence is also
visible. As of August 2015, 13 of his papers had gathered more than 200 citations. The
most cited paper on the Aharonov-Bohm effect had 3,731 citations; it is followed by the
paper on the reinterpretation of quantum mechanics with 2,451; and the paper on
electron gas, with D. Pines, with 1,185 citations (Bohm 1952, Bohm and Pines 1953,
Aharonov and Bohm 1959). However, his reputation fluctuated. From being considered
a promising young physicist, his reputation was damaged by the poor and adverse
reception of his work on the foundations of quantum mechanics; exemplifying the bias
against the research on foundations in the 1950s. After the experiments related to Bell’s
theorem, interest in his early work was slowly resumed. Ultimately, this theorem and its
experiments set entanglement as a strictly quantum feature and shed light on the
equivalence between standard quantum mechanics and Bohm’s interpretation. Both of
these feature quantum entanglement as one of their features while they provide different
explanations. In the 1980s, he saw the revival of his early approach to quantum
mechanics, which was referred to as Bohmian mechanics (Dürr, Goldstein et al. 1996).
Thus, recognition for his outstanding contributions came later, as noted by his old friend
physicist Melba Phillips, in the early 1990s: “It is too bad, very sad indeed, that he did
not live to see how his reputation has shot up recently. His interpretation of quantum
mechanics is becoming respected not only by philosophers of science but also by
‘straight’ physicists” (Freire Junior 2015, p. 63)
In hindsight how can we assess Bohm’s legacy to quantum physics? In addition
to specific and lasting contributions, I think he should be acknowledged for his attitude
which highlighted the relevance of the research on the foundations of this theory. John
Bell’s recollections about how he was driven to these issues encapsulate this feeling: “In
1952 I saw the impossible done,” referring to the appearance of the causal interpretation
which was considered by current wisdom an impossible feat.
Bohm’s personal life reflected the circumstances and vicissitudes of the 20th
century, in politics and culture at large. Before WWII, he joined the Communist Party
thinking that this was the right way to oppose the rising Nazi regime in Europe. After
being acquitted, his contract at Princeton was not renewed (Olwell 1999, Freire Jr.
2005, Mullet 2008a, Mullet 2008b). In 1951, he left the US for a job in Brazil and later
went to Israel and eventually the United Kingdom in 1957. Reflecting the Cold War
times, his passport was apprehended by US officials in Brazil and his American
citizenship cancelled. In order to get a passport to travel abroad, he applied and got
Brazilian citizenship. He only recovered his American citizenship 30 years later, in the
twilight of the Cold War and through a legal procedure. He lived for almost 3 decades
as one of the most notable American expatriate scientists. In the late 1950s, following
the Soviet invasion of Hungary, he broke his ideological ties with Marxism and later
moved towards a rapprochement with Eastern thinkers such as Jiddu Krishnamurti. He
then became an iconic figure in the New Age culture of the1960s and 1970s. His life
illustrates much of the political and cultural turmoil of the times.
Bohm’s life circumstances and work in physics were mingled enough to lead
commentators to highlight the strong influences of the former on the latter. Alex
Kojevnikov (2002) suggested his approach to plasma and electrons in metals in terms of
collective variables reflected his early Marxist commitments. Christian Forstner (2008)
saw his move towards the causal interpretation as conditioned both by his Marxist views
and his insulation from Princeton community during the apex of his McCarthyist
persecution. I suggest his moving away from the causal interpretation, in the late 1950s,
was influenced by his break with the ideological ties of Communism; however, while
some commentators have suggested that the poor reception of the causal interpretation
was influenced by his persecution in McCarthy times, I found this suggestion
unfounded (Freire Junior 2015). Other commentators have suggested a strong link
between his implicit order approach and the inclination he developed towards Eastern
thinkers, which requires further historical and epistemological investigation. As a result,
I suggest that the biography I am proposing takes into account connections among
Bohm’s ideas in science and his personal background. Needless to emphasize, such
connections, if any, need to be corroborated by documentary evidence in order to be
included in a scholarly historical work.
Bohm’s biography is thus, in itself, a subject of interest to physicists and physics
students. It may also be a window from which to view the changes in science as well as
relations between science and the political and cultural history of the 20th century. If
Biography in history and in history of science
While biographies have been bestsellers for decades, they are late comers in
historiographical scholarship. The reason for this was professional distrust towards a
kind of historical work usually related to the description of heroes and saints.
Interestingly, it is from here that the term hagiography comes, the deadliest sin
committed by professional historians. The Annales school did not reject it; however,
they assimilated it to the description of social archetypes of historical ages. It was more
recently that the genre was fully recovered through the approach the French historian
François Dosse (2010) calls the hermeneutical stage in the biography historiographical
fortune. The historian has no ambition to represent the individual as a coherent character
in his times, instead, fractures, contradictions, and conflicts should be enlightened.
Jacques Le Goff’s portrait of Saint Louis is an exemplar of this updated approach (Le
Goff 1996). In the history of science the trajectory of biographies was no different.
Replacing heroes and saints with individual geniuses, most biographies in science were
idealized descriptions of these outstanding scientists (Kragh 1987). While most of full
series of Newton’s biographies illustrate this trend, more recent works, such as the
Never at Rest, Newton’s biography by Richard Westfall (1980), illustrates how off scale
individual and contributions can be accommodated in a biographical portrait full of
other human features. Our challenge is thus to write a scientific biography of David
Bohm in tune with the current standards of the discipline.
Why a second biography of Bohm?
As there already exists a biography of Bohm, written by F. David Peat, the first question
to be raised is what is the point of writing a second biography? A trivial answer would
be that many great physicists have received more than one biography and Bohm was a
great scientist. A more substantive answer requires considering the strong and weak
aspects in this biography. While well written, and extensively based on letters and
interviews in addition to personal acquaintance with Bohm, this biography is more a
biography of Bohm’s life than of Bohm’s ideas. To be more precise, in key points in the
development of Bohm’s quest to understand quantum theory and its philosophical
implications, Peat’s book is too shallow and sometimes mistaken. Let me illustrate with
text in the full book (Peat 1997, pp. 168-170). Peat did not distinguish the two papers by
Bell (Bell 1964, Bell 1966), which were published in the inverse order of their
production, one dealing with von Neumann’s proof and Bohm’s causal interpretation,
and the second suggesting what we call now Bell’s theorem. Therefore the conundrum
involved in that proof and Bohm’s and Bell’s works is simply ignored. The book did not
discuss how Bohm reacted to Bell’s theorem at all. Bohm evolved from an initial
misunderstanding of Bell’s theorem to a full comprehension of its implication.
Furthermore, Bohm grasped these implications at a moment (Bohm and Hiley 1975)
when there were still conflicting experimental results, those from Clauser & Freedman
at Berkeley, confirming quantum mechanics and those from Holt & Pipkin at Harvard,
confirming local theories. Only after Clauser replication of Holt’s experiment and
mainly after Fry & Thompson experiment in 1976, did the balance incline towards
quantum mechanics and its non-locality. Instead of analyzing this rich moment, Peat
simply and quickly stated the following: “Soon after Bell’s theorem was published, a
number of experimental tests, each one more refined and each one designed to
overcome possible objections, confirmed the essential nonlocality of the quantum
world” (Peat 1997, p. 170). Thus, Peat’s book ignored both the science content and the
human drama of those ten years between the appearance of the Bell’s theorem and the
full vindication of quantum mechanics nonlocality, which later was dubbed
entanglement. In fact, characters such as John Clauser, Abner Shimony, Ed Fry, Alain
Aspect, and Bernard d’Espagnat are meaningfully absent in this biography. Thus a new
biography of Bohm is in order, one integrating the history of his ideas and the history of
his life, all articulated in their relevant contexts.
My relationship with David Bohm’s work
I have been working on Bohm’s ideas since my Ph.D., obtained in 1995 at the
University of São Paulo under the supervision of Michel Paty and Shozo Motoyama. I
analyzed Bohm’s interpretation of quantum theory and its reception in the 1950s. While
working on the research for my book, The Quantum Dissidents, Bohm was a major
player. Thus I consulted archival materials on Bohm in different places, such as the
Bohm Papers at Birkbeck College; the Center for History of Physics at the American
Institute of Physics; the Niels Bohr Archive in Copenhagen; Princeton University;
University of São Paulo, among others. Furthermore, as part of that research I
conducted or consulted a number of oral histories with physicists who worked on the
foundations of quantum mechanics and many of them have useful information on
Bohm’s work. Particularly useful for this biography were talks or interviews with Basil
Hiley, Jeffrey Bub, and Jayme Tiomno. However, additional research needs to be done,
but a good portion of the research has already been done. In particular, I need to carry
out additional research into his stay in Israel and his work with Aharonov as well as on
his connections with Krishnamurti in London.
Finally, a sample, and kind of state of the art, of my approach to Bohm’s work is
Chapter 2 of my The Quantum Dissidents.
References
Aharonov, Y. and D. Bohm (1959). "Significance of Electromagnetic Potentials in the Quantum Theory." Physical Review 115(3): 485-491.
Bell, J. S. (1964). "On the Einstein Podolsky Rosen Paradox." Physics 1: 195-200.
Bell, J. S. (1966). "On the Problem of Hidden Variables in Quantum Mechanics." Reviews of Modern Physics 38(3): 447-452.
Bohm, D. (1952). "A Suggested Interpretation of the Quantum Theory in Terms of Hidden Variables - I & II." Physical Review 85(2): 166-179, 180-193.
Bohm, D. and B. J. Hiley (1993). The undivided universe : an ontological interpretation of quantum theory. London ; New York, Routledge.
Bohm, D., et al. (1987). Quantum implications : essays in honour of David Bohm. New York, Routledge & Kegan Paul.
Bohm, D. and D. Pines (1953). "A Collective Description of Electron Interactions .3. Coulomb Interactions in a Degenerate Electron Gas." Physical Review 92(3): 609-625.
Bohm, D. J. and B. J. Hiley (1975). "Intuitive Understanding of Nonlocality as Implied by Quantum-Theory." Foundations of Physics 5(1): 93-109.
Dürr, D., et al. (1996). Bohmian mechanics at the foundation of quantum mechanics. Bohmian mechanics and quantum theory: an appraisal. J. T. Cushing, A. Fine and S. Goldstein. Dordrecht, Kluwer: 21-44.
Forstner, C. (2008). "The early history of David Bohm's quantum mechanics through the perspective of Ludwik Fleck's thought-collectives." Minerva 46(2): 215-229.
Freire Jr., O. (2005). "Science and exile: David Bohm, the cold war, and a new
interpretation of quantum mechanics." Historical Studies in the Physical and Biological Sciences 36(1): 1-34.
Freire Junior, O. (2015). The quantum dissidents : rebuilding the foundations of quantum mechanics (1950-1990). Heidelberg, Springer.
Kojevnikov, A. (2002). "David Bohm and collective movement." Historical Studies in the Physical and Biological Sciences 33: 161-192.
Kragh, H. (1987). An Introduction to the Historiography of Science. Cambridge, Cambridge University Press
Le Goff, J. (1996). Saint Louis. Paris, Gallimard.
Mullet, S. K. (2008a). Little Man: Four Junior Physicists and the Red Scare Experience, Harvard University. PhD Dissertation.
Mullet, S. K. (2008b). Bohm, David Joseph. New Dictionary of Scientific Biography. N. Koertge. New York, Thomson - Gale. I: 321-326.
Olwell, R. (1999). "Physical Isolation and Marginalization in Physics - David Bohm's Cold War Exile." ISIS 90(738-756).
Peat, F. D. (1997). Infinite potential : the life and times of David Bohm. Reading, Mass., Addison Wesley.
Philippidis, C., et al. (1979). "Quantum Interference and the Quantum Potential." Nuovo Cimento Della Societa Italiana Di Fisica B-General Physics Relativity Astronomy and Mathematical Physics and Methods 52(1): 15-28.
