David Bohm

David Joseph Bohm (20 December 1917 – 27 October 1992) was an American–Brazilian–British scientist who has been described as one of the most significant theoretical physicists of the 20th century and who contributed unorthodox ideas to quantum theory, neuropsychology and the philosophy of mind.

Among his many contributions to physics is his causal and deterministic interpretation of quantum theory known as De Broglie–Bohm theory.

Bohm advanced the view that quantum physics meant that the old 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.

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.

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.

Bohm warned of the dangers of rampant reason and technology, advocating instead the need for genuine supportive dialogue, which he claimed could bridge and unify conflicting and troublesome divisions in the social world.

In this, his epistemology mirrored his ontology.

Born in the United States, Bohm obtained his Ph.D. under J. Robert Oppenheimer at the University of California, Berkeley.

Bohm attended 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, the Campus Committee to Fight Conscription, and the Committee for Peace Mobilization.

During his time at the Radiation Laboratory, Bohm was in a relationship with Betty Friedan and 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).

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 project's director, Brigadier General Leslie Groves, would not approve Bohm's security clearance after seeing evidence of his politics and his close friendship with Weinberg, who had been suspected of espionage.

During the war, Bohm remained at Berkeley, where he taught physics and conducted research in plasma, the synchrotron and the synchrocyclotron.

He completed his PhD in 1943 by an unusual circumstance.

According to biographer F. David Peat, "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 Calutrons at the Y-12 facility in Oak Ridge, Tennessee.

These calculations were used for the electromagnetic enrichment of uranium for the bomb dropped on Hiroshima in 1945.

After the war, Bohm became an assistant professor at Princeton University.

He also worked closely with Albert Einstein at the nearby Institute for Advanced Study.

Although Einstein considered appointing him as his research assistant at the Institute, Oppenheimer (who had served as the Institute's president since 1947) "opposed the idea and [...] advised his former student to leave the country".

His request to go to the University of Manchester received Einstein's support but was unsuccessful.

Bohm then left for Brazil to assume a professorship of physics at the University of São Paulo, at Jayme Tiomno's invitation and on the recommendation of both Einstein and Oppenheimer.

During his early period, Bohm made a number of significant contributions to physics, particularly quantum mechanics and relativity theory.

As a postgraduate at Berkeley, he developed a theory of plasmas, discovering the electron phenomenon known as Bohm diffusion.

Due to his Communist affiliations, he was the subject of a federal government investigation in 1949, prompting him to leave the U.S. He pursued his career in several countries, becoming first a Brazilian and then a British citizen.

In May 1949, the House Un-American Activities Committee called upon Bohm to testify because of his previous ties to unionism and suspected communists.

Bohm invoked his Fifth Amendment right to refuse to testify, and he refused to give evidence against his colleagues.

In 1950, Bohm was arrested for refusing to answer the committee's questions.

He was acquitted in May 1951, but Princeton had already suspended him.

After his acquittal, Bohm's colleagues sought to have him reinstated at Princeton, but Princeton President Harold W. Dodds decided not to renew Bohm's contract.

His first book, Quantum Theory, published in 1951, was well received by Einstein, among others.

He abandoned Marxism in the wake of the Hungarian Uprising in 1956.

Bohm was born in Wilkes-Barre, Pennsylvania, to a Hungarian Jewish immigrant father, Samuel Bohm, 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.