| ethnicity = [[History of the Jews in Hungary|Hungarian]]–[[Lithuanian Jews|Lithuanian Jewish]]
| fields = [[Theoretical physics]]
| workplaces = {{Unbulleted list |item_style=padding:0.15em 0;line-height:1.15em | [[Manhattan Project]] | [[Princeton University]] | [[University of São Paulo]] | [[Technion]] | [[University of Bristol]] | [[Birkbeck, University of London|Birkbeck College, London]]}}
| alma_mater = {{Unbulleted list |item_style=padding:0.15em 0;line-height:1.15em | [[Pennsylvania State University|Pennsylvania State College]]<!-- {{smaller|(to 1939)}}--> | [[California Institute of Technology]]<!-- {{smaller|(1939–40)}}--> | [[University of California, Berkeley]]<!-- {{smaller|(PhD 1943)}}-->}}
| awards = {{Unbulleted list |item_style=padding:0.15em 0;line-height:1.15em | 1991 [[Elliott Cresson Medal]] | 1990 [[Fellow of the Royal Society|Royal Society fellowship]]<!--<ref name="frs"/>-->}}
| signature = | footnotes =
}}
}}
'''David Joseph Bohm''' [[Fellow of the Royal Society|FRS]]<ref name="frs">{{Cite journal | last1 = Hiley | first1 = B. J. | authorlink = Basil Hiley| doi = 10.1098/rsbm.1997.0007 | title = David Joseph Bohm. 20 December 1917--27 October 1992: Elected F.R.S. 1990 | journal = [[Biographical Memoirs of Fellows of the Royal Society]] | volume = 43 | pages = 107–131 | year = 1997 | pmid = | pmc = }}</ref> ({{IPAc-en|b|oʊ|m}}; December 20, 1917 – October 27, 1992) was an American scientist who has been described as one of the most significant [[Theoretical physics|theoretical]] [[physicist]]s of the 20th century<ref name="DavidPeat">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}}.</ref> and who contributed unorthodox ideas to [[quantum mechanics|quantum theory]], [[neuropsychology]] and the [[philosophy of mind]].
'''David Joseph Bohm''' (December 20, 1917 – October 27, 1992) was an American-born theoretical physicist whose work stands as the most fully developed alternative to the orthodox Copenhagen interpretation of quantum mechanics. In 1952 he constructed a '''causal''', deterministic account of quantum theory in which particles follow definite trajectories guided by a real physical field — demonstrating that the "hidden variables" the physics establishment had declared impossible were not impossible at all.
Bohm advanced the view that quantum physics meant that the old [[Dualism (philosophy of mind)|Cartesian model]] of reality – that there are two kinds of substance, the mental and the physical, that somehow interact – was too limited. To complement it, he developed a mathematical and physical theory of [[Implicate and explicate order|"implicate" and "explicate" order]].<ref name="wholeness">David Bohm: ''Wholeness and the Implicate Order'', Routledge, 1980 ({{ISBN|0-203-99515-5}}).</ref> He also believed that the brain, at the cellular level, works according to the mathematics of some quantum effects, and postulated that thought is distributed and non-localised just as quantum entities are.<ref name="holo"/>{{Failed verification|date=July 2014}}
Bohm's career is a case study of how unorthodox physics is received. He was driven out of the United States by the anti-communist purges, spent the rest of his life in exile, and saw his interpretation ignored for decades despite making the same experimental predictions as the orthodoxy. His work is nonetheless the direct ancestor of [[John Stewart Bell|Bell's]] theorem and of the modern field of quantum foundations.
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 [[ontology]].<ref>David Bohm: On Dialogue (2004) Routledge</ref> Due to his [[Communist]] affiliations, Bohm was the subject of a federal government investigation in 1949, prompting him to leave the United States. He pursued his scientific career in several countries, becoming first a [[Brazil]]ian and then a [[British citizen]].
==Early life and education==
Bohm's main concern was with understanding the nature of reality in general and of consciousness in particular as a coherent whole, which according to Bohm is never static or complete but rather an unfolding process.<ref>''Wholeness and the Implicate Order'', Bohm - July 4, 2002</ref>
Bohm was born in Wilkes-Barre, Pennsylvania, in 1917. He studied at Pennsylvania State College and then at the University of California, Berkeley, where he completed his doctorate under J. Robert Oppenheimer and worked on plasma physics — the field in which the effect now called '''Bohm diffusion''' bears his name. He went on to a faculty position at Princeton University, where he wrote the well-regarded textbook ''Quantum Theory'' (1951), a careful exposition of the orthodox view that he came to doubt in the course of writing it.
== Biography ==
==HUAC and exile==
===Youth and college===
In the McCarthy era Bohm was summoned before the House Un-American Activities Committee and refused to testify against colleagues. He was arrested in December 1949 on a charge of contempt of Congress. Although he was '''acquitted''', Princeton had already barred him from campus and declined to renew his contract.
Bohm was born in [[Wilkes-Barre, Pennsylvania|Wilkes-Barre]], Pennsylvania, United States, to a [[Hungarian Jewish]] immigrant father, Samuel Bohm,<ref>http://ed.augie.edu/~wjdelfs/381bohm.htm{{dead link|date=December 2017 |bot=InternetArchiveBot |fix-attempted=yes }} - By the Numbers – David Bohm</ref> 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 [[agnosticism|agnostic]] in his teenage years.<ref>{{cite book |title=Infinite Potential: The Life And Times Of David Bohm |year=1997 |publisher=[[Basic Books]] |isbn=978-0-201-32820-2 |author=[[F. David Peat]] |page=21 |quote=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.}}<!--|accessdate=16 April 2012 --></ref> Bohm attended [[Pennsylvania State University#Early years|Pennsylvania State College]] (now Pennsylvania State University), graduating in 1939, and then the [[California Institute of Technology]], for one year. He then transferred to the theoretical physics group directed by [[Robert Oppenheimer]] at the [[University of California, Berkeley]] Radiation Laboratory, 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 in radical politics. He was active in Communist and Communist-backed organizations, including the [[Young Communist League, USA|Young Communist League]], the Campus Committee to Fight Conscription, and the [[American Peace Mobilization|Committee for Peace Mobilization]]. During his time at the Radiation Laboratory Bohm also helped to organize a local chapter of the [[Federation of Architects, Engineers, Chemists and Technicians]], a small labor union affiliated to the [[Congress of Industrial Organizations]] (CIO).<ref name=Garber>{{cite book |last1=Garber |first1=Marjorie |last2=Walkowitz |first2=Rebecca |date=1995 |title=Secret Agents: The Rosenberg Case, McCarthyism and Fifties America |url=https://books.google.com.au/books?id=Ae2OAQAAQBAJ |location=New York|publisher=Routledge |pages=130–131 |isbn=9781135206949 |author-link1=Marjorie Garber}}</ref>
Despite being a leading authority on plasma physics, Bohm could find no academic post in the United States or Europe. He emigrated to the University of São Paulo in Brazil, and later worked in Israel before settling in England at Birkbeck College, London, where he remained until his death in 1992. His landmark hidden-variable papers were written and published in the first years of this exile.
===Work and doctorate===
==The causal interpretation==
====Manhattan Project contributions====
In two papers of 1952, Bohm set out what he first called a hidden-variable theory and later the '''causal''' or '''ontological''' interpretation. In it, a particle is a real object with a definite position and trajectory at all times, guided by its wave function acting through a '''quantum potential'''. Measurement reveals pre-existing properties rather than creating them; there is no collapse of the wave function, and no need for an observer to bring reality into being.
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 National Laboratory|Los Alamos]] (the top-secret laboratory established in 1942 to design the atom bomb), the project's director, General [[Leslie Groves]], would not approve Bohm's security clearance after seeing evidence of 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. Bohm later performed theoretical calculations for the [[Calutron]]s at the [[Y-12 National Security Complex|Y-12]] facility in [[Oak Ridge, Tennessee|Oak Ridge]], used to [[Isotope separation#Electromagnetic|electromagnetically enrich uranium]] for the bomb dropped on [[Hiroshima]] in 1945.
The theory reproduces all the standard predictions of quantum mechanics. Its significance was therefore not empirical but conceptual: it showed that the indeterminism and observer-dependence of the Copenhagen interpretation are '''interpretive choices, not consequences of the evidence'''.
====McCarthyism and leaving the United States====
This mattered because John von Neumann's 1932 "impossibility proof" was widely held to have ruled out hidden-variable theories altogether, and had been used for two decades to foreclose the question. Bohm's construction was a working counterexample. The philosopher Grete Hermann had in fact identified the flaw in von Neumann's argument as early as 1935, but her critique was overlooked; the defect was independently rediscovered and made widely known by [[John Stewart Bell]], who wrote that Bohm had shown explicitly what had been declared out of the question. Bell's own celebrated work on non-locality grew directly out of engaging with Bohm's theory.
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 because of his previous ties to suspected Communists. Bohm invoked his [[Fifth amendment rights of witness|Fifth amendment]] right to refuse to testify, and refused to give evidence against his colleagues.
In 1950 Bohm was arrested for refusing to answer HUAC's questions. He was acquitted in May 1951, but Princeton had already suspended him. After the acquittal, Bohm's colleagues sought to have him reinstated at Princeton, and Einstein reportedly wanted him to serve as his assistant, but Princeton President [[Harold W. Dodds]]<ref>Russell Olwell: [http://web.mit.edu/sts/pubs/pdfs/MIT_STS_WorkingPaper_20_Olwell.pdf ''Physics and Politics in Cold War America: The Two Exiles of David Bohm''], Working Paper Number 20. Program in Science, Technology, and Society. Massachusetts Institute of Technology.</ref> decided not to renew Bohm's contract. His request to go to Manchester received Einstein's support but was unsuccessful.<ref>Albert Einstein to Patrick Blackett, 17 April 1951 (Albert Einstein archives). Cited after [[Olival Freire, Jr.]]: ''[http://www.controversia.fis.ufba.br/index_arquivos/Freire-Bohm-HSPS.pdf Science and Exile: David Bohm, the cold war, and a new interpretation of quantum mechanics] {{webarchive |url=https://web.archive.org/web/20120326192406/http://www.controversia.fis.ufba.br/index_arquivos/Freire-Bohm-HSPS.pdf |date=26 March 2012 }}'', HSPS, vol. 36, Part 1, pp. 1–34, ISSN 0890-9997, 2005, see footnote 8.</ref> Bohm then left for Brazil to assume a professorship of physics at the [[University of São Paulo]] at [[Jayme Tiomno]]'s invitation, and on Einstein's and Oppenheimer's recommendation.
The price of the theory — and the point on which mainstream physicists most often reject it — is that it is explicitly '''non-local''': the guiding field connects distant particles instantaneously. Proponents reply that Bell's theorem subsequently showed that ''any'' theory reproducing quantum predictions must be non-local, so Bohm's model makes explicit a feature the orthodoxy merely conceals.
[[File:doppelspalt.svg|thumb|180px|The Bohmian trajectories for an electron going through the two-slit experiment. A similar pattern was also observed for single photons.<ref>http://www.sciencemag.org/content/332/6034/1170.figures-only – Observing the Average Trajectories of Single Photons in a Two-Slit Interferometer</ref>]]
During his early period, Bohm made a number of significant contributions to physics, particularly [[quantum mechanics]] and [[relativity theory]]. As a post-graduate at Berkeley, he developed a theory of [[plasma (physics)|plasmas]], discovering the [[electron]] phenomenon known now as [[Bohm-diffusion]].<ref>D. Bohm: ''The characteristics of electrical discharges in magnetic fields'', in: A. Guthrie, R. K. Wakerling (eds.), McGraw–Hill, 1949</ref> His first book, ''Quantum Theory'', published in 1951, was well received by Einstein, among others. But Bohm became dissatisfied with the orthodox interpretation of quantum theory 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.<ref>[[Maurice A. de Gosson]], Basil J. Hiley: ''Zeno paradox for Bohmian trajectories: the unfolding of the metatron'', January 3, 2011 ([http://www.freewebs.com/cvdegosson/ZenoPaper.pdf PDF] – retrieved 16 February 2012)</ref>
Bohm's aim was not to set out a deterministic, mechanical viewpoint, but to show that it was possible to attribute properties to an underlying reality, in contrast to the conventional approach.<ref>B. J. Hiley: [http://www.bbk.ac.uk/tpru/BasilHiley/History_of_Bohm_s_QT.pdf ''Some remarks on the evolution of Bohm's proposals for an alternative to quantum mechanics''], 30 January 2010</ref> He began to develop his own interpretation (the [[De Broglie–Bohm theory]], also called the [[Pilot wave]] theory), the predictions of which agreed perfectly with the non-deterministic quantum theory. He initially referred to his approach as a [[hidden variable theories|hidden variable]] theory, but later referred to it as ''ontological theory'', reflecting his view that a stochastic process underlying the phenomena described by his theory might one day be found. Bohm and his colleague [[Basil Hiley]] later stated that they had found their own choice of terms of an "interpretation in terms of hidden variables" to be too restrictive, especially since their variables, position, and momentum "are not actually hidden".<ref>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}}, [https://books.google.com/books?id=vt9XKjc4WAQC&pg=PA2 p. 2]</ref>
In his later work Bohm moved beyond interpretation toward a broader account of nature, set out in ''Wholeness and the Implicate Order'' (1980). He proposed that the manifest world of separate objects — the '''explicate order''' — unfolds from a deeper, undivided '''implicate order''' in which everything is enfolded in everything else. This holistic conception was intended to replace the fragmentation he regarded as endemic to modern science and thought, and it brought him an audience well beyond physics, including his long dialogue with the philosopher Jiddu Krishnamurti.
Bohm's work and the [[EPR paradox|EPR argument]] became the major factor motivating [[John Stewart Bell|John Bell]]'s [[Bell's inequality|inequality]], which rules out [[locality principle|local]] hidden variable theories; the full consequences of Bell's work are still being investigated.
==Other contributions==
====Brazil====
With Yakir Aharonov, Bohm predicted in 1959 the '''Aharonov–Bohm effect''', in which a charged particle is measurably affected by an electromagnetic potential in a region where the fields themselves vanish — demonstrating that potentials are physically real rather than mere mathematical conveniences. He also made lasting contributions to plasma physics, including Bohm diffusion, and to the theory of metals with the Bohm–Pines treatment of plasmons.
After Bohm's arrival in Brazil on October 10, 1951, the US Consul in [[São Paulo]] confiscated his passport, informing him he could retrieve it only to return to his country. This reportedly frightened Bohm,<ref>Russell Olwell: ''[http://web.mit.edu/sts/pubs/pdfs/MIT_STS_WorkingPaper_20_Olwell.pdf 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]]</ref> and significantly lowered his spirits, as he had hoped to travel to Europe. He applied for and received [[Brazilian nationality law|Brazilian citizenship]], but by law had to give up his [[Citizenship of the United States|US citizenship]] and was able to reclaim it only decades later, in 1986, after pursuing a lawsuit.<ref name="freire">[[Olival Freire, Jr.]]: ''[http://www.controversia.fis.ufba.br/index_arquivos/Freire-Bohm-HSPS.pdf Science and Exile: David Bohm, the cold war, and a new interpretation of quantum mechanics] {{webarchive |url=https://web.archive.org/web/20120326192406/http://www.controversia.fis.ufba.br/index_arquivos/Freire-Bohm-HSPS.pdf |date=26 March 2012 }}'', HSPS, vol. 36, Part 1, pp. 1–34, ISSN 0890-9997, 2005</ref>
At the University of São Paulo, Bohm worked on the causal theory that became the subject 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]], [[José Leite Lopes|Leite Lopes]], and had discussions on occasion with visitors to Brazil, including [[Richard Feynman]], [[Isidor Rabi]], [[Léon Rosenfeld]], [[Carl Friedrich von Weizsäcker]], [[Herbert L. Anderson]], [[Donald Kerst]], [[Marcos Moshinsky]], Alejandro Medina, and the former assistant to [[Werner Heisenberg|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 [[Erwin Madelung|Madelung]].<ref>{{cite web | url=http://www.uni-frankfurt.de/fb/fb13/Dateien/paf/paf73.html | title=Erwin Madelung 1881–1972 | publisher=[[Goethe University Frankfurt|Goethe-Universität Frankfurt am Main]] | date=12 December 2008 | accessdate=May 8, 2012 | deadurl=yes | archiveurl=https://web.archive.org/web/20120212130742/http://www.uni-frankfurt.de/fb/fb13/Dateien/paf/paf73.html | archivedate=12 February 2012 | df=dmy-all }}</ref> 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.<ref name="freire"/>
==Reception==
From 1951 to 1953, Bohm and [[David Pines]] published the articles in which they introduced the [[random phase approximation]] and proposed the [[plasmon]].<ref>{{cite journal|author1=Pines, D |author2=Bohm, D. A|title=''Collective Description of Electron Interactions. I. Magnetic Interactions''|journal=Physical Review|volume=82|pages=625–634|year=1951|doi=10.1103/physrev.82.625|bibcode = 1951PhRv...82..625B }}</ref><ref>{{cite journal|author1=Pines, D |author2=Bohm, D. A|title=Collective Description of Electron Interactions: II. Collective vs Individual Particle Aspects of the Interactions|journal=Physical Review|volume=85|pages=338–353|year=1952|doi=10.1103/physrev.85.338|bibcode = 1952PhRv...85..338P }}</ref><ref>{{cite journal|author1=Pines, D |author2=Bohm, D.|title=A Collective Description of Electron Interactions: III. Coulomb Interactions in a Degenerate Electron Gas|journal=Physical Review|volume=92|pages=609–626|year=1953|doi=10.1103/physrev.92.609|bibcode = 1953PhRv...92..609B }}</ref>
For decades Bohm's interpretation was largely absent from textbooks and teaching, and it remains a minority position. Critics judge it superfluous, since it makes no distinct predictions, and object to its non-locality and its privileged particle positions. Its defenders — and the critical tradition documented on this wiki — regard the neglect as revealing: a self-consistent, empirically adequate alternative was set aside less on evidence than on the authority of a proof that turned out to be flawed, and against a background in which its author had been made professionally untouchable.
====Bohm and Aharonov form of the EPR paradox====
==Related work on this wiki==
In 1955 Bohm relocated to Israel, where he spent two years working at the [[Technion]] at [[Haifa]]. There he met Sarah ("Saral") Woolfson, whom he married in 1956.
In 1957 Bohm and his student [[Yakir Aharonov]] published a new version of the [[EPR paradox|Einstein–Podolsky–Rosen (EPR) paradox]], reformulating the original argument in terms of spin.<ref>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 ([http://prola.aps.org/abstract/PR/v108/i4/p1070_1 abstract])</ref> It was this form of the EPR paradox that was discussed by [[John Stewart Bell]] in his famous paper of 1964.<ref>J.S. Bell, On the Einstein Podolsky Rosen paradox, ''Physics'', vol. 1, no. 3, pp. 195–200</ref>
Related material catalogued here includes work on the Aharonov–Bohm effect, such as ''[[The Aharonov-Bohm Phase Shift Related to Strain in the Vortex Sponge]]'' and ''[[Physics' Lingering Indecision in Making Choices Between Schroedinger and Aharanov-Bohm Processing]]''. Bohm's causal tradition connects directly to [[Louis de Broglie]] and to [[Jean Pierre Vigier]], who developed a stochastic version of the same programme.
====Aharonov–Bohm effect====
==See also==
{{main article|Aharonov–Bohm effect}}
[[File:Aharonov-Bohm effect.svg|thumbnail|right|210px|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, University of London|Birkbeck College]], becoming emeritus in 1987. His collected papers are stored there.<ref>[http://www.aim25.ac.uk/cgi-bin/search2?coll_id=3070&inst_id=33 collected papers]</ref>
====Implicate and explicate order====
* [[Louis de Broglie]]
{{main article|Implicate and explicate order}}
* [[Jean Pierre Vigier]]
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.<ref name="wholeness"/><ref>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}}, [http://www.springerlink.com/content/l2474245pw272842/ abstract]</ref><ref>David Bohm, F. David Peat: ''[[Science, Order, and Creativity]]'', 1987</ref> 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 (physics)|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.<ref>Basil J. Hiley: ''Process and the Implicate Order: their relevance to Quantum Theory and Mind.'' ([http://www.ctr4process.org/publications/Articles/LSI05/Hiley%20paper.pdf PDF] {{webarchive |url=https://web.archive.org/web/20110926212330/http://www.ctr4process.org/publications/Articles/LSI05/Hiley%20paper.pdf |date=26 September 2011 }})</ref>
[[File:Holography-reconstruct.png|thumb|200px|right|In a holographic reconstruction, each region of a photographic plate contains the whole image.]]
[[Category:Worldwide List of Dissident Scientists]]
In collaboration with [[Stanford]] neuroscientist [[Karl H. Pribram|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.<ref name = "holo">[http://www.acsa2000.net/bcngroup/jponkp/#chap4 Comparison between Karl Pribram's "Holographic Brain Theory" and more conventional models of neuronal computation<!-- Bot generated title -->]</ref>{{Failed verification|date=July 2014}} 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.<ref>[http://homepages.ihug.co.nz/~sai/pribram.htm The holographic brain], with Karl Pribram</ref>
====Consciousness and thought====
In addition to his scientific work, Bohm was deeply interested in exploring the nature of consciousness, with particular attention to the role of thought as it relates to attention, motivation, and conflict in the individual and in society. These concerns were a natural extension of his earlier interest in [[Marxist ideology]] and [[Hegelian philosophy]]. His views were brought into sharper focus through extensive interactions with the psychological philosopher [[Jiddu Krishnamurti]], beginning in 1961.<ref name="Years">{{cite book|author=[[Mary Lutyens]]|title=[[Krishnamurti: The Years of Fulfillment]]|chapter=Freedom is Not Choice|chapterurl=https://books.google.co.nz/books?redir_esc=y&id=WKmJndX5B8wC&q=208#v=snippet&q=208&f=false|year=1983|publisher=Krishnamurti Foundation Trust Ltd.|isbn=0-900506-20-2|page=208}}</ref><ref name="Uncommon">{{cite book|author=David Edmund Moody|title=An Uncommon Collaboration: David Bohm and J. Krishnamurti|url=https://books.google.com/books/about/An_Uncommon_Collaboration.html?id=2gZjvgAACAAJ|year=2016|publisher=Alpha Centauri Press|isbn=978-0692854273|page=}}</ref> Their collaboration lasted a quarter of a century, and their recorded dialogues were published in several volumes.<ref name="T&A">{{cite book|author= J. Krishnamurti|title=Truth and Actuality|url=https://books.google.com/books?id=zYIF1nO4cdkC&pg|year=2000|publisher=Krishnamurti Foundation Trust Ltd.|isbn=978-8187326182|page=}}</ref><ref name="Ending">{{cite book|author= J. Krishnamurti and D. Bohm|title=The Ending of Time|url=https://books.google.com/books?id=hjtb1RhYeVkC&dq|year=1985|publisher=HarperCollins|isbn=978-0060647964|page=}}</ref><ref name="Limits">{{cite book|author= J. Krishnamurti and D. Bohm|title=The Limits of Thought: Discussions between J. Krishnamurti and David Bohm |url=https://books.google.com/books?id=At2FAgAAQBAJ&pg|year=1999|publisher=Routledge|isbn=978-0415193986|page=}}</ref>
Bohm’s prolonged involvement with the philosophy of Krishnamurti was regarded somewhat skeptically by some of his scientific peers.<ref name="Infinite">{{cite book|author= F. David Peat|title=Infinite Potential: The Life and Times of David Bohm |url=https://books.google.com/books?id=pobZMUmZbAEC|year=1997|publisher=Basic Books|isbn=978-0201328202|page=}}</ref><ref name="SI"/> A more recent and extensive examination of the relationship between the two men presents it in a more positive light and shows that Bohm’s work in the psychological field was complementary to and compatible with his contributions to theoretical physics.<ref name="Uncommon"/>
The mature expression of Bohm’s views in the psychological field was presented in a seminar conducted in 1990 at the [[Oak Grove School (Ojai, California)|Oak Grove School]], founded by Krishnamurti in [[Ojai, California]]. This was one of a series of seminars held by Bohm at Oak Grove School and it was published as ''Thought as a System''.<ref name="Thought">{{cite book|author= David Bohm|title=Thought as a System|url=https://books.google.com/books/about/Thought_as_a_System.html?id=9Q-3WN0LajsC|year=1994|publisher=Psychology Press|isbn=978-0415110303|page=}}</ref> In this seminar, Bohm described the pervasive influence of thought throughout society, including the many erroneous assumptions about the nature of thought and its effects in daily life.
In this seminar, Bohm develops several interrelated themes. He points out that thought is the ubiquitous tool we use to solve every kind of problem – personal, social, scientific, and so on. And yet, he maintains, thought is inadvertently the source of many of these problems. He recognizes and acknowledges the irony of this situation – it is as if one gets sick by going to the doctor.<ref name="Uncommon"/><ref name="Thought"/>
Bohm maintains that thought is a system, in the sense that it is an interconnected network of concepts, ideas and assumptions that pass seamlessly between individuals and throughout society. If there is a fault in the functioning of thought, therefore, it must be a systemic fault, one that infects the entire network. The thought that we bring to bear to resolve any given problem, therefore, is susceptible to the same flaw that created the problem it is trying to solve.<ref name="Uncommon"/><ref name="Thought"/>
Thought proceeds as if it is merely reporting objectively, but in fact it is often coloring and distorting perception in unexpected ways. What is required in order to correct the distortions introduced by thought, according to Bohm, is a form of proprioception, or self-awareness. We have neural receptors throughout the body that inform us directly of our physical position and movement, but there is no corresponding awareness of the activity of thought. Such an awareness would represent psychological proprioception and would enable the possibility of perceiving and correcting the unintended consequences of the thinking process.<ref name="Uncommon"/><ref name="Thought"/>
====Further interests====
In his book ''On Creativity'', quoting the work of [[Alfred Korzybski]], Bohm expressed the view that "metaphysics is an expression of a world view" and is "thus to be regarded as an art form, resembling poetry in some ways and mathematics in others, rather than as an attempt to say something true about reality as a whole."<ref>{{cite book|author=David Bohm|title=On Creativity|url=https://books.google.com/books?id=Mcd4SsIjVKUC&pg=PA118|date=12 October 2012|publisher=Routledge|isbn=978-1-136-76818-7|pages=118}}</ref>
Bohm was keenly aware of various ideas outside the scientific mainstream. In his book ''Science, Order and Creativity'', Bohm referred to the views of various biologists on the evolution of the species, including [[Rupert Sheldrake]].<ref name="BohmPeat2014">{{cite book|author1=David Bohm|author2=F. David Peat|title=Science, Order and Creativity Second Edition|url=https://books.google.com/books?id=4ZTsAgAAQBAJ&pg=PA204|date=25 February 2014|publisher=Routledge|isbn=978-1-317-83546-2|pages=204–}}</ref> He also knew the ideas of [[Wilhelm Reich]].<ref name="Peat1997">{{cite book|author=F. David Peat|title=Infinite Potential: The Life and Times of David Bohm|url=https://books.google.com/books?id=1JPvAAAAMAAJ|year=1997|publisher=Addison Wesley|isbn=978-0-201-40635-1|page=80}}</ref>
Contrary to many other scientists, Bohm did not exclude the [[paranormal]] out of hand. Bohm temporarily even held [[Uri Geller]]'s bending of keys and spoons to be possible, prompting warning remarks by his colleague [[Basil Hiley]] that this might undermine the scientific credibility of their work in physics. [[Martin Gardner]] reported this in a ''[[Skeptical Inquirer]]'' article, and also critiqued the views of [[Jiddu Krishnamurti]], whom Bohm had encountered in 1959 and had had many subsequent exchanges with. Gardner said that Bohm's view of the interconnectedness of mind and matter (on one occasion summarized as "Even the electron is informed with a certain level of mind"<ref>{{cite book|title=Quantum Implications: Essays in Honour of David Bohm|publisher=Routledge|year=2012|isbn=9781134914173|page=443|editor1=Hiley, Basil|editor2=Peat, F. David}}</ref>) "flirted with [[panpsychism]]".<ref name="SI">{{cite web|url=http://thinkg.net/david_bohm/martin_gardner_on_david_bohm_and_krishnamurti.html|title=David Bohm and Jiddo Krishnamurti|last=Gardner|first=Martin|date=July 2000|work=Skeptical Inquirer|deadurl=yes|archiveurl=https://web.archive.org/web/20150309114214/http://thinkg.net/david_bohm/martin_gardner_on_david_bohm_and_krishnamurti.html|archivedate=9 March 2015|df=dmy-all}}</ref>
====Bohm dialogue====
<!-- This section is linked from [[Change management]] -->
{{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 in this form of dialogue is that participants "suspend" immediate action or judgment and 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 Bohm observed in society.
===Later years===
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 [[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 Maré]], and had a series of meetings with the [[Dalai Lama]]. He was elected [[Fellow of the Royal Society]] in 1990.<ref name="frs"/>
Near the end of his life, Bohm began to experience a recurrence of the [[depression (mood)|depression]] he had suffered earlier in 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 longtime 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. But his depression returned and was treated with medication.<ref name="F. David Peat 1997, pp. 308–317">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}}.</ref>
Bohm died after suffering a [[myocardial infarction|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 found that Bohm had collapsed.<ref name="F. David Peat 1997, pp. 308–317">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}}.</ref>
=== Reception of Bohm's causal program ===
During the early 1950s Bohm's causal quantum theory program was mostly negatively received, with a widespread tendency among physicists to systematically ignore both Bohm personally and his ideas. There was a significant revival of interest in Bohm's ideas in the late 1950s and the early 1960s, with the Ninth Symposium of the Colston Research Society in Bristol in 1957 a key turning point toward greater tolerance of Bohm's ideas.<ref>{{Cite journal|last=Kožnjak|first=Boris|date=2017|title=The missing history of Bohm’s hidden variables theory: the Ninth Symposium of the Colston Research Society, Bristol, 1957|url=http://www.sciencedirect.com/science/article/pii/S1355219817300539|journal=Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics|volume=|pages=|via=}}</ref>
== Publications ==
* 1951. ''Quantum Theory'', New York: [[Prentice Hall]]. 1989 [https://books.google.com/books/about/Quantum_Theory.html?id=-vhCqN2twGQC reprint], New York: Dover, {{ISBN|0-486-65969-0}}
* 1957. ''Causality and Chance in Modern Physics'', 1961 Harper edition reprinted in 1980 by Philadelphia: U of Pennsylvania Press, {{ISBN|0-8122-1002-6}}
* 1962. ''Quanta and Reality, A Symposium'', with [[N. R. Hanson]] and [[Mary B. Hesse]], from a [[BBC]] program published by the American Research Council
* 1965. ''The Special Theory of Relativity'', New York: W.A. Benjamin.
* 1980. ''[[Wholeness and the Implicate Order]]'', London: Routledge, {{ISBN|0-7100-0971-2}}, 1983 Ark paperback: {{ISBN|0-7448-0000-5}}, 2002 paperback: {{ISBN|0-415-28979-3}}
* 1985. ''Unfolding Meaning: A weekend of dialogue with David Bohm'' (Donald Factor, editor), Gloucestershire: Foundation House, {{ISBN|0-948325-00-3}}, 1987 Ark paperback: {{ISBN|0-7448-0064-1}}, 1996 Routledge paperback: {{ISBN|0-415-13638-5}}
* 1985. ''The Ending of Time'', with Jiddu Krishnamurti, San Francisco: Harper, {{ISBN|0-06-064796-5}}.
* 1987. ''[[Science, Order, and Creativity]]'', with [[F. David Peat]]. London: Routledge. 2nd ed. 2000. {{ISBN|0-415-17182-2}}.
* 1989. ''[https://archive.is/20111009151609/http://www.tkpi.org/content/meaning-and-information-david-bohm Meaning And Information]'', In: P. Pylkkänen (ed.): ''The Search for Meaning: The New Spirit in Science and Philosophy'', Crucible, The Aquarian Press, 1989, {{ISBN|978-1-85274-061-0}}.
* 1991. ''Changing Consciousness: Exploring the Hidden Source of the Social, Political and Environmental Crises Facing our World'' (a dialogue of words and images), coauthor Mark Edwards, Harper San Francisco, {{ISBN|0-06-250072-4}}
* 1992. ''Thought as a System'' (transcript of seminar held in [[Ojai, California]], from 30 November to 2 December 1990), London: Routledge. {{ISBN|0-415-11980-4}}.
* 1993. ''The Undivided Universe: An ontological interpretation of quantum theory'', with [[Basil Hiley|B.J. Hiley]], London: Routledge, {{ISBN|0-415-12185-X}} (final work)
* "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}} [https://web.archive.org/web/20040412155034/http://fdavidpeat.com/ 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 ==
* William Keepin: [https://books.google.com/books?id=toNYaUmzWpUC&pg=PA5 ''A life of dialogue between science and spirit – David Bohm'']. In World Scriptures: Leland P. Stewart (ed.): ''Guidelines for a Unity-and-Diversity Global Civilization'', World Scriptures Vol. 2, AuthorHouse. (2009) {{ISBN|978-1-4389-8086-7}}, pp. 5–13
* William Keepin: [https://www.scribd.com/doc/61375478/Lifework-of-David-Bohm ''Lifework of David Bohm. River of Truth''], Re-vision, vol. 16, no. 1, 1993, p. 32 (online at [[scribd]])
== External links ==
{{Wikiquote}}
* [http://dbohm.com/ The David Bohm Society]
* [http://bohmkrishnamurti.com/ The Bohm Krishnamurti Project: Exploring the Legacy of the David Bohm and Jiddu Krishnamurti Relationship]
* [http://www.david-bohm.net David Bohm's ideas about Dialogue]
* [https://web.archive.org/web/20050421132413/http://www.thinkg.net/david_bohm/ the David_Bohm_Hub]. Includes compilations of David Bohm's life and work in form of texts, audio, video, and pictures
* [http://www.vision.net.au/~apaterson/science/david_bohm.htm#BOHM'S%20LEGACY Lifework of David Bohm: River of Truth]: Article by Will Keepin ([http://www.gaia.dk/international/externalarticles/bohm-lifework.pdf PDF-version])
* [https://web.archive.org/web/20010303172350/http://www.fdavidpeat.com/interviews/bohm.htm Interview with David Bohm] provided and conducted by [[F. David Peat]] along with [[John Briggs (author)|John Briggs]], first issued in [[Omni (magazine)|''Omni'' magazine]], January 1987
* [http://www.bbk.ac.uk/lib/about/hours/bohm Archive of papers at Birkbeck College relating to David Bohm] and [http://www.nationalarchives.gov.uk/a2a/records.aspx?cat=1832-ncuacs66497&cid=-1#-1 David Bohm at the National Archives]
* [http://genealogy.math.ndsu.nodak.edu/id.php?id=106535 David Bohm] at the [[Mathematics Genealogy Project]]
* [http://www.aip.org/history/ohilist/4513.html Oral History interview transcript with David Bohm 8 May 1981], [[American Institute of Physics]], Niels Bohr Library and Archives
* [http://manhattanprojectvoices.org/oral-histories/david-bohms-interview 1979 Audio Interview with David Bohm] by [[Martin Sherwin]] at [[Voices of the Manhattan Project]]
* [http://thebohmdocumentary.org/ ''The Bohm Documentary''] by David Peat and Paul Howard (in production)
{{FRS 1990}}
{{Footer Neuropsychology}}
{{Manhattan Project}}
{{Use dmy dates|date=January 2011}}
{{Authority control}}
{{DEFAULTSORT:Bohm, David}}
[[Category:1917 births]]
[[Category:1992 deaths]]
[[Category:20th-century American philosophers]]
[[Category:Academics of Birkbeck, University of London]]
[[Category:Alumni of the University of Bristol]]
[[Category:American agnostics]]
[[Category:American emigrants to England]]
[[Category:American people of Hungarian-Jewish descent]]
[[Category:American people of Lithuanian-Jewish descent]]
[[Category:American physicists]]
[[Category:English agnostics]]
[[Category:English Jews]]
[[Category:English philosophers]]
[[Category:English physicists]]
[[Category:Consciousness researchers and theorists]]
[[Category:Disease-related deaths in England]]
[[Category:Fellows of the Royal Society]]
[[Category:Jewish agnostics]]
[[Category:Jewish American scientists]]
[[Category:Jewish philosophers]]
[[Category:Manhattan Project people]]
[[Category:People from Wilkes-Barre, Pennsylvania]]
[[Category:Quantum mind]]
[[Category:Quantum physicists]]
[[Category:University of São Paulo faculty]]
[[Category:American emigrants to Brazil]]
[[Category:American expatriates in Israel]]
[[Category:Naturalised citizens of the United Kingdom]]
David Joseph Bohm (December 20, 1917 – October 27, 1992) was an American-born theoretical physicist whose work stands as the most fully developed alternative to the orthodox Copenhagen interpretation of quantum mechanics. In 1952 he constructed a causal, deterministic account of quantum theory in which particles follow definite trajectories guided by a real physical field — demonstrating that the "hidden variables" the physics establishment had declared impossible were not impossible at all.
Bohm's career is a case study of how unorthodox physics is received. He was driven out of the United States by the anti-communist purges, spent the rest of his life in exile, and saw his interpretation ignored for decades despite making the same experimental predictions as the orthodoxy. His work is nonetheless the direct ancestor of Bell's theorem and of the modern field of quantum foundations.
Early life and education
Bohm was born in Wilkes-Barre, Pennsylvania, in 1917. He studied at Pennsylvania State College and then at the University of California, Berkeley, where he completed his doctorate under J. Robert Oppenheimer and worked on plasma physics — the field in which the effect now called Bohm diffusion bears his name. He went on to a faculty position at Princeton University, where he wrote the well-regarded textbook Quantum Theory (1951), a careful exposition of the orthodox view that he came to doubt in the course of writing it.
HUAC and exile
In the McCarthy era Bohm was summoned before the House Un-American Activities Committee and refused to testify against colleagues. He was arrested in December 1949 on a charge of contempt of Congress. Although he was acquitted, Princeton had already barred him from campus and declined to renew his contract.
Despite being a leading authority on plasma physics, Bohm could find no academic post in the United States or Europe. He emigrated to the University of São Paulo in Brazil, and later worked in Israel before settling in England at Birkbeck College, London, where he remained until his death in 1992. His landmark hidden-variable papers were written and published in the first years of this exile.
The causal interpretation
In two papers of 1952, Bohm set out what he first called a hidden-variable theory and later the causal or ontological interpretation. In it, a particle is a real object with a definite position and trajectory at all times, guided by its wave function acting through a quantum potential. Measurement reveals pre-existing properties rather than creating them; there is no collapse of the wave function, and no need for an observer to bring reality into being.
The theory reproduces all the standard predictions of quantum mechanics. Its significance was therefore not empirical but conceptual: it showed that the indeterminism and observer-dependence of the Copenhagen interpretation are interpretive choices, not consequences of the evidence.
This mattered because John von Neumann's 1932 "impossibility proof" was widely held to have ruled out hidden-variable theories altogether, and had been used for two decades to foreclose the question. Bohm's construction was a working counterexample. The philosopher Grete Hermann had in fact identified the flaw in von Neumann's argument as early as 1935, but her critique was overlooked; the defect was independently rediscovered and made widely known by John Stewart Bell, who wrote that Bohm had shown explicitly what had been declared out of the question. Bell's own celebrated work on non-locality grew directly out of engaging with Bohm's theory.
The price of the theory — and the point on which mainstream physicists most often reject it — is that it is explicitly non-local: the guiding field connects distant particles instantaneously. Proponents reply that Bell's theorem subsequently showed that any theory reproducing quantum predictions must be non-local, so Bohm's model makes explicit a feature the orthodoxy merely conceals.
Implicate and explicate order
In his later work Bohm moved beyond interpretation toward a broader account of nature, set out in Wholeness and the Implicate Order (1980). He proposed that the manifest world of separate objects — the explicate order — unfolds from a deeper, undivided implicate order in which everything is enfolded in everything else. This holistic conception was intended to replace the fragmentation he regarded as endemic to modern science and thought, and it brought him an audience well beyond physics, including his long dialogue with the philosopher Jiddu Krishnamurti.
Other contributions
With Yakir Aharonov, Bohm predicted in 1959 the Aharonov–Bohm effect, in which a charged particle is measurably affected by an electromagnetic potential in a region where the fields themselves vanish — demonstrating that potentials are physically real rather than mere mathematical conveniences. He also made lasting contributions to plasma physics, including Bohm diffusion, and to the theory of metals with the Bohm–Pines treatment of plasmons.
Reception
For decades Bohm's interpretation was largely absent from textbooks and teaching, and it remains a minority position. Critics judge it superfluous, since it makes no distinct predictions, and object to its non-locality and its privileged particle positions. Its defenders — and the critical tradition documented on this wiki — regard the neglect as revealing: a self-consistent, empirically adequate alternative was set aside less on evidence than on the authority of a proof that turned out to be flawed, and against a background in which its author had been made professionally untouchable.