David Bohm

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David Bohm
David Bohm.jpg
Born (1917-12-20)December 20, 1917
Wilkes-Barre, Pennsylvania, United States
Died October 27, 1992(1992-10-27) (aged 74)
London, England
Citizenship American, Brazilian and British
Fields Physics
Institutions Manhattan Project
Princeton University
University of São Paulo
Technion
University of Bristol
Birkbeck College, London
Alma mater Pennsylvania State College (graduated 1939)
California Institute of Technology (1939–1940)
University of California, Berkeley (PhD, 1943)
Doctoral advisor Robert Oppenheimer
Doctoral students Yakir Aharonov
David Pines
Jeffrey Bub
Henri Bortoft
Marvin Weinstein
Known for Bohm-diffusion
Bohm interpretation/De Broglie–Bohm theory
Bohm's hidden variable theory
Bohm quantum potential
Aharonov–Bohm effect
Einstein–Podolsky–Rosen–Bohm paradox
Holographic paradigm
Holomovement
Holonomic brain theory
Bohm Dialogue
Bohm criterion
Nonradiation condition
Pilot wave
Implicate and explicate order
Random phase approximation
Quantum decoherence
Quantum mind
Influences Albert Einstein
Jiddu Krishnamurti
Influenced John Stewart Bell
Notable awards Fellow of the Royal Society[1]
Elliott Cresson Medal (1991)

David Joseph Bohm FRS[1] (20 December 1917 – 27 October 1992) was an American theoretical physicist who contributed innovative and unorthodox ideas to quantum theory, philosophy of mind, and neuropsychology. He is considered to be one of the most significant theoretical physicists of the 20th century.[2]

Bohm advanced the view that the old Cartesian model of reality (that there were two interacting kinds of substance - mental and physical) was limited, in the light of developments in quantum physics. He developed in detail a mathematical and physical theory of implicate and explicate order to complement it.[3] He also believed that the working of the brain, at the cellular level, obeyed the mathematics of some quantum effects, and postulated that thought was distributed and non-localised in the way that quantum entities do not readily fit into our conventional model of space and time.[4][not in citation given]

Bohm warned of the dangers of rampant reason and technology, advocating instead the need for genuine supportive dialogue which he claimed could broaden and unify conflicting and troublesome divisions in the social world. In this his epistemology mirrored his ontological viewpoint.[5] Due to his youthful Communist affiliations, Bohm was targeted during the McCarthy era, leading him to leave the United States. He pursued his scientific career in several countries, becoming first a Brazilian, then a British, citizen.

Biography[edit]

Youth and college[edit]

Bohm was born in Wilkes-Barre, Pennsylvania, United States, to a Hungarian Jewish immigrant father and a Lithuanian Jewish mother. He was raised mainly by his father, a furniture-store owner and assistant of the local rabbi. Despite being raised in a Jewish family, he became an agnostic in his teenage years.[6] Bohm attended Pennsylvania State College (now Pennsylvania State University), graduating in 1939, then the California Institute of Technology for a year. He then transferred to the theoretical physics group directed by Robert Oppenheimer at the University of California, Berkeley, where he obtained his doctorate.

Bohm lived in the same neighborhood as some of Oppenheimer's other graduate students (Giovanni Rossi Lomanitz, Joseph Weinberg, and Max Friedman) and with them became increasingly involved not only with physics, but with radical politics. Bohm became active in Communist and Communist-backed organizations including the Young Communist League, the Campus Committee to Fight Conscription, and the Committee for Peace Mobilization.

Work and doctorate[edit]

Manhattan Project contributions[edit]

During World War II, the Manhattan Project mobilized much of Berkeley's physics research in the effort to produce the first atomic bomb. Though Oppenheimer had asked Bohm to work with him at Los Alamos (the top-secret laboratory established in 1942 to design the atom bomb), the director of the Manhattan Project, General Leslie Groves, would not approve Bohm's security clearance, after evidence about his politics (Bohm's friend, Joseph Weinberg, had also been suspected of espionage).

Bohm remained in Berkeley, teaching physics, until he completed his Ph.D. in 1943, by an unusual circumstance. According to Peat (see reference below, p. 64), "the scattering calculations (of collisions of protons and deuterons) that he had completed proved useful to the Manhattan Project and were immediately classified. Without security clearance, Bohm was denied access to his own work; not only would he be barred from defending his thesis, he was not even allowed to write his own thesis in the first place!" To satisfy the university, Oppenheimer certified that Bohm had successfully completed the research. He later performed theoretical calculations for the Calutrons at the Y-12 facility in Oak Ridge, used to electromagnetically enrich uranium for use in the bomb dropped on Hiroshima in 1945.

McCarthyism leads to Bohm leaving the United States[edit]

After the war, Bohm became an assistant professor at Princeton University, where he worked closely with Albert Einstein. In May, 1949, the House Un-American Activities Committee called upon Bohm to testify before it— because of his previous ties to suspected Communists. Bohm, however, pleaded the Fifth amendment right to refuse to testify, and refused to give evidence against his colleagues.

In 1950, Bohm was charged for refusing to answer questions of the Committee and was arrested. He was acquitted in May, 1951, but Princeton University had already suspended him. After the acquittal, Bohm's colleagues sought to have him re-instated to Princeton, and Einstein reportedly wanted Bohm to serve as his assistant. The university did not renew his contract. His request to go to Manchester found support with Einstein, but was unsuccessful.[7] Bohm then left for Brazil to assume a professorship of physics at the University of São Paulo at the invitation of Jayme Tiomno, and by recommendation of Einstein and Oppenheimer.

Quantum theory and Bohm-diffusion[edit]

The Bohmian trajectories for an electron going through the two-slit experiment. The similar pattern was also observed for single photons.[8]

During his early period, Bohm made a number of significant contributions to physics, particularly to quantum mechanics and relativity theory. As a post-graduate at Berkeley, he developed a theory of plasmas, discovering the electron phenomenon known now as Bohm-diffusion.[9] His first book, Quantum Theory published in 1951, was well received by Einstein, among others. However, Bohm became dissatisfied with the orthodox interpretation of quantum theory, which he had written about in that book. Starting from the realization that the WKB approximation of quantum mechanics leads to deterministic equations and convinced that a mere approximation could not turn a probabilistic theory into a deterministic theory, he doubted the inevitability of the conventional approach to quantum mechanics.[10]

Bohm's aim was not to set out a deterministic, mechanical viewpoint, but rather to show that it was possible to attribute properties to an underlying reality, in contrast to the conventional approach.[11] He began to develop his own interpretation (De Broglie–Bohm theory), the predictions of which agree perfectly with the nondeterministic quantum theory. He initially referred to his approach as a hidden variable theory, but later referred to it as ontological theory, reflecting his view that a stochastic process that would underlie the phenomena described by his theory may be found. Bohm and his colleague Basil Hiley later stated that they found their own choice of terms of an "interpretation in terms of hidden variables" to be too restrictive, in particular as their variables, position and momentum, "are not actually hidden".[12]

Bohm's work and the EPR argument became the major factor motivating John Bell's inequality, which rules out local hidden variable theories; the full consequences of Bell's work are still being investigated.

Brazil years[edit]

After his arrival in Brazil on October 10, 1951, the U.S. Consul in São Paulo had confiscated his passport, informing him he could retrieve it only to return to his country. This reportedly frightened Bohm,[13] and significantly lowered his spirits, as he had hoped to travel to Europe. He applied for and received Brazilian citizenship, but due to then-Brazilian law he had to give up his U.S. citizenship and could retrieve it only decades later, in 1986, after pursuing a lawsuit.[14]

At the University of São Paulo, Bohm worked on the causal theory that became the object of his publications in 1952. Jean-Pierre Vigier traveled to São Paulo, where he worked with Bohm for three months; Ralph Schiller (a student of cosmologist Peter Bergmann) was his assistant for two years; he worked with Tiomno and Walther Schützer; and Mario Bunge stayed to work with him for one year. He was in contact with Brazilian physicists Mário Schönberg, Jean Meyer, Leite Lopes, and had discussions on occasions with visitors to Brazil, including Richard Feynman, Isidor Rabi, Léon Rosenfeld, Carl Friedrich von Weizsäcker, Herbert Anderson, Donald Kerst, Marcos Moshinsky, Alejandro Medina, and the former assistant to Heisenberg, Guido Beck, who encouraged him in his work and helped him to obtain funding. The Brazilian CNPq explicitly supported his work on the causal theory and funded several researchers around Bohm. His work with Vigier was the beginning of a long-standing cooperation between the two and Louis De Broglie, in particular, on connections to the hydrodynamics model proposed by Madelung.[15] Yet the causal theory met much resistance and skepticism, with many physicists holding the Copenhagen interpretation to be the only viable approach to quantum mechanics.[14]

Bohm and Aharonov form of the EPR paradox[edit]

In 1955, Bohm relocated to Israel, where he spent two years working at the Technion at Haifa. Here he met Sarah Woolfson (also called Saral). The couple married in 1956.

In 1957, Bohm and his student Yakir Aharonov published a new version of the Einstein–Podolsky–Rosen (EPR) paradox, reformulating the original argument in terms of spin.[16] It was this form of the EPR paradox that was discussed by John Stuart Bell in his famous paper of 1964.[17]

Aharonov–Bohm effect[edit]

Schematic of double-slit experiment in which Aharonov–Bohm effect can be observed: electrons pass through two slits, interfering at an observation screen, with the interference pattern shifted when a magnetic field B is turned on in the cylindrical solenoid.

In 1957, Bohm relocated to the United Kingdom as a research fellow at the University of Bristol. In 1959, Bohm and Aharonov discovered the Aharonov–Bohm effect, showing how a magnetic field could affect a region of space in which the field had been shielded, although its vector potential did not vanish there. This showed for the first time that the magnetic vector potential, hitherto a mathematical convenience, could have real physical (quantum) effects. In 1961, Bohm was made Professor of Theoretical Physics at the University of London's Birkbeck College, where his collected papers are kept.

Implicate and explicate order[edit]

At Birkbeck College, much of the work of Bohm and Basil Hiley expanded on the notion of implicate, explicate and generative orders proposed by Bohm.[3][18][19] In the view of Bohm and Hiley, "things, such as particles, objects, and indeed subjects" exist as "semi-autonomous quasi-local features" of an underlying activity. These features can be considered to be independent only up to a certain level of approximation in which certain criteria are fulfilled. In this picture, the classical limit for quantum phenomena, in terms of a condition that the action function is not much greater than Planck's constant, indicates one such criterion. They used the word holomovement for the activity in such orders.[20]

Holonomic model of the brain[edit]

In a holographic reconstruction, each region of a photographic plate contains the whole image

In collaboration with Stanford neuroscientist Karl Pribram, Bohm was involved in the early development of the holonomic model of the functioning of the brain, a model for human cognition that is drastically different from conventionally accepted ideas.[4][not in citation given] Bohm worked with Pribram on the theory that the brain operates in a manner similar to a hologram, in accordance with quantum mathematical principles and the characteristics of wave patterns.[21]

Thought as a System[edit]

Bohm was alarmed by what he considered an increasing imbalance of not only man and nature, but among peoples, as well as within people, themselves. Bohm mused: "So one begins to wonder what is going to happen to the human race. Technology keeps on advancing with greater and greater power, either for good or for destruction." He goes on to ask:

What is the source of all this trouble? I'm saying that the source is basically in thought. Many people would think that such a statement is crazy, because thought is the one thing we have with which to solve our problems. That's part of our tradition. Yet it looks as if the thing we use to solve our problems with is the source of our problems. It's like going to the doctor and having him make you ill. In fact, in 20% of medical cases we do apparently have that going on. But in the case of thought, it's far over 20%.

In Bohm's view:

...the general tacit assumption in thought is that it's just telling you the way things are and that it's not doing anything – that 'you' are inside there, deciding what to do with the info. But you don't decide what to do with the info. Thought runs you. Thought, however, gives false info that you are running it, that you are the one who controls thought. Whereas actually thought is the one which controls each one of us.

Thought is creating divisions out of itself and then saying that they are there naturally. This is another major feature of thought: Thought doesn't know it is doing something and then it struggles against what it is doing. It doesn't want to know that it is doing it. And thought struggles against the results, trying to avoid those unpleasant results while keeping on with that way of thinking. That is what I call "sustained incoherence".

Bohm thus proposes in his book, Thought as a System, a pervasive, systematic nature of thought:

What I mean by "thought" is the whole thing – thought, felt, the body, the whole society sharing thoughts – it's all one process. It is essential for me not to break that up, because it's all one process; somebody else's thoughts become my thoughts, and vice versa. Therefore it would be wrong and misleading to break it up into my thoughts, your thoughts, my feelings, these feelings, those feelings... I would say that thought makes what is often called in modern language a system. A system means a set of connected things or parts. But the way people commonly use the word nowadays it means something all of whose parts are mutually interdependent – not only for their mutual action, but for their meaning and for their existence. A corporation is organized as a system – it has this department, that department, that department. They don't have any meaning separately; they only can function together. And also the body is a system. Society is a system in some sense. And so on.

Similarly, thought is a system. That system not only includes thoughts, "felts" and feelings, but it includes the state of the body; it includes the whole of society – as thought is passing back and forth between people in a process by which thought evolved from ancient times. A system is constantly engaged in a process of development, change, evolution and structure changes...although there are certain features of the system which become relatively fixed. We call this the structure.... Thought has been constantly evolving and we can't say when that structure began. But with the growth of civilization it has developed a great deal. It was probably very simple thought before civilization, and now it has become very complex and ramified and has much more incoherence than before.

Now, I say that this system has a fault in it – a "systematic fault". It is not a fault here, there or here, but it is a fault that is all throughout the system. Can you picture that? It is everywhere and nowhere. You may say "I see a problem here, so I will bring my thoughts to bear on this problem". But "my" thought is part of the system. It has the same fault as the fault I'm trying to look at, or a similar fault.

Thought is constantly creating problems that way and then trying to solve them. But as it tries to solve them it makes it worse because it doesn’t notice that it's creating them, and the more it thinks, the more problems it creates. (pp. 18–19)

Bohm views physical processes as determined by information of more and more subtle levels which interact, and does not limit this consideration to matter alone. In an article of 1990, A new theory of the relationship of mind and matter, he resumes his view that there exists a close link to mental processes: "the whole notion of active information suggests a rudimentary mind-like behaviour of matter". In his view, mental processes as well can be understood as representing levels of activity of increasing subtlety which act upon each other. He recalls that thought is intricately connected with physical reactions, as is known from everyday experience. Yet on the mental side, action as response to information need not be immediate; rather, in some cases at least, it can be mediated by "suspension" of physical action and the resulting train of thought.[22]

Bohm suggests that the mental and the physical sides, which he sees as two "poles" of a unified whole, are closely interlinked and that "at each level, information is the bridge or link between the two sides". A relationship between the mental and matter may exist at indefinitely great levels of subtlety, while nonetheless each kind and level of mind may have a relative autonomy and stability. His article concludes with the statement that "knowledge of matter (as well as of mind) has changed in such a way as to support the approach that has been described here. To pursue this approach further might perhaps enable us to extend our knowledge of both poles into new domains".[22]

Bohm Dialogue[edit]

Main article: Bohm Dialogue

To address societal problems during his later years, Bohm wrote a proposal for a solution that has become known as "Bohm Dialogue", in which equal status and "free space" form the most important prerequisites of communication and the appreciation of differing personal beliefs. An essential ingredient to this form of dialogue is that participants "suspend" immediate action or judgement and that they give themselves and each other the opportunity to become aware of the thought process itself. Bohm suggested that if these "dialogue groups" were experienced on a sufficiently wide scale, they could help overcome the isolation and fragmentation which Bohm observed was currently present in society.

Later years[edit]

Bohm continued his work in quantum physics past his retirement in 1987. His final work, the posthumously published The Undivided Universe: An Ontological Interpretation of Quantum Theory (1993), resulted from a decades-long collaboration with his colleague Basil Hiley. He also spoke to audiences across Europe and North America on the importance of dialogue as a form of sociotherapy, a concept he borrowed from London psychiatrist and practitioner of Group Analysis Patrick De Mare, and had a series of meetings with the Dalai Lama. He was elected Fellow of the Royal Society in 1990.[1]

Near the end of his life, Bohm began to experience a recurrence of depression which he had suffered at earlier times in his life. He was admitted to the Maudsley Hospital in South London on 10 May 1991. His condition worsened and it was decided that the only treatment that might help him was electroconvulsive therapy. Bohm's wife consulted psychiatrist David Shainberg, Bohm's long-time friend and collaborator, who agreed that electroconvulsive treatments were probably his only option. Bohm showed improvement from the treatments and was released on 29 August. However, his depression returned and was treated with medication.[23]

Bohm died after suffering a heart attack in Hendon, London, on 27 October 1992, aged 74. He had been traveling in a London taxicab on that day; after getting no response from the passenger in the back seat for a few seconds, the driver turned back and found that Bohm had collapsed.[23]

Publications[edit]

See also[edit]

Notes[edit]

  1. ^ a b c Hiley, B. J. (1997). "David Joseph Bohm. 20 December 1917--27 October 1992: Elected F.R.S. 1990". Biographical Memoirs of Fellows of the Royal Society 43: 107. doi:10.1098/rsbm.1997.0007.  edit
  2. ^ F. David Peat, Infinite Potential: The Life and Times of David Bohm, Reading, Massachusetts: Addison Wesley, 1997, pp. 316-317. ISBN 0-201-32820-8.
  3. ^ a b David Bohm: Wholeness and the Implicate Order, 1980, Routledge, ISBN 0-203-99515-5
  4. ^ a b Comparison between Karl Pribram's "Holographic Brain Theory" and more conventional models of neuronal computation
  5. ^ David Bohm: On Dialogue (2004) Routledge
  6. ^ F. David Peat (1997). Infinite Potential: The Life And Times Of David Bohm. Basic Books. p. 21. ISBN 978-0-201-32820-2. "If he identified Jewish lore and customs with his father, then this was a way he would distance himself from Samuel. By the time he reached his late teens, he had become firmly agnostic." 
  7. ^ Albert Einstein to Patrick Blackett, 17 April 1951 (Albert Einstein archives). Cited after Olival Freire, Jr.: Science and Exile: David Bohm, the cold war, and a new interpretation of quantum mechanics, HSPS, vol. 36, Part 1, pp. 1–34, ISSN 0890-9997, 2005, see footnote 8.
  8. ^ http://www.sciencemag.org/content/332/6034/1170.figures-only – Observing the Average Trajectories of Single Photons in a Two-Slit Interferometer
  9. ^ D. Bohm: The characteristics of electrical discharges in magnetic fields, in: A. Guthrie, R. K. Wakerling (eds.), McGraw–Hill, 1949
  10. ^ Maurice A. de Gosson, Basil J. Hiley: Zeno paradox for Bohmian trajectories: the unfolding of the metatron, January 3, 2011 (PDF - retrieved 16 February 2012)
  11. ^ B. J. Hiley: Some remarks on the evolution of Bohm's proposals for an alternative to quantum mechanics, 30 January 2010
  12. ^ David Bohm, Basil Hiley: The Undivided Universe: An Ontological Interpretation of Quantum Theory, edition published in the Taylor & Francis e-library 2009 (first edition Routledge, 1993), ISBN 0-203-98038-7, p. 2
  13. ^ Russell Olwell: Physics and politics in cold war America: the two exiles of David Bohm, Working Paper Number 2, Working Program in Science, Technology, and Society; Massachusetts Institute of Technology
  14. ^ a b Olival Freire, Jr.: Science and Exile: David Bohm, the cold war, and a new interpretation of quantum mechanics, HSPS, vol. 36, Part 1, pp. 1–34, ISSN 0890-9997, 2005
  15. ^ "Erwin Madelung 1881–1972". Goethe-Universität Frankfurt am Main. 12 December 2008. Retrieved May 8, 2012. 
  16. ^ D. Bohm, Y. Aharonov (1957), Discussion of Experimental Proof for the Paradox of Einstein, Rosen, and Podolsky, Phys. Rev., vol. 108, no. 4, pp. 1070–1076 (abstract)
  17. ^ J.S. Bell, On the Einstein Podolsky Rosen paradox, Physics, vol. 1, no. 3, pp. 195–200
  18. ^ David Bohm, Basil J. Hiley, Allan E. G. Stuart: On a new mode of description in physics, International Journal of Theoretical Physics, vol. 3, no. 3, pp. 171–183, doi:10.1007/BF00671000, abstract
  19. ^ David Bohm, F. David Peat: Science, Order, and Creativity, 1987
  20. ^ Basil J. Hiley: Process and the Implicate Order: their relevance to Quantum Theory and Mind. (PDF)
  21. ^ The holographic brain, with Karl Pribram
  22. ^ a b David Bohm: A new theory of the relationship of mind and matter, Philosophical Psychology, vol. 3, no. 2, 1990, pp. 271—286, doi:10.1080/09515089008573004
  23. ^ a b F. David Peat, Infinite Potential: The Life and Times of David Bohm, Reading, Massachusetts: Addison Wesley, 1997, pp. 308–317. ISBN 0-201-32820-8.

References[edit]

  • "Bohm's Alternative to Quantum Mechanics", David Z. Albert, Scientific American (May, 1994)
  • Brotherhood of the Bomb: The Tangled Lives and Loyalties of Robert Oppenheimer, Ernest Lawrence, and Edward Teller, Herken, Gregg, New York: Henry Holt (2002) ISBN 0-8050-6589-X (information on Bohm's work at Berkeley and his dealings with HUAC)
  • Infinite Potential: the Life and Times of David Bohm, F. David Peat, Reading, Massachusetts: Addison Wesley (1997), ISBN 0-201-40635-7 DavidPeat.com
  • Quantum Implications: Essays in Honour of David Bohm, (B.J. Hiley, F. David Peat, editors), London: Routledge (1987), ISBN 0-415-06960-2
  • Thought as a System (transcript of seminar held in Ojai, California, from 30 November to 2 December 1990), London: Routledge. (1992) ISBN 0-415-11980-4.
  • The Quantum Theory of Motion: an account of the de Broglie-Bohm Causal Interpretation of Quantum Mechanics, Peter R. Holland, Cambridge: Cambridge University Press. (2000) ISBN 0-521-48543-6.

Further reading[edit]

External links[edit]