J. Robert Oppenheimer[1] (April 22, 1904 – February 18,
1967) was an American theoretical physicist, best known for his role as the director of the Manhattan Project, the World War II effort to develop the first
nuclear weapons, at the secret Los
Alamos laboratory in New Mexico. Known as "the father of the atomic bomb," Oppenheimer was shocked by the weapon's killing power after it was used to destroy the
Japanese cities of Hiroshima and
Nagasaki. Quoting from the Bhagavad Gita, he said "If the radiance of a thousand suns were to burst at once into the sky,
that would be like the splendor of the mighty one. Now I am become Death, the destroyer of worlds."
After the war, Oppenheimer was a chief advisor to the newly created United States Atomic Energy Commission and used that position to lobby for
international control of atomic energy and to avert
the nuclear arms race with the Soviet Union.
After invoking the ire of many politicians and scientists with his outspoken political opinions during the Red Scare, he had his security clearance revoked in a
much-publicized and politicized hearing in 1954. Though stripped of his direct political influence, Oppenheimer continued to
lecture, write, and work in physics. A decade later, President John F. Kennedy awarded him the
Enrico Fermi Award as a gesture of political rehabilitation. As a scientist, Oppenheimer is
remembered most for being the chief founder of the American school of theoretical physics while at the University of California, Berkeley.
Early life and education
Oppenheimer was born to Julius S. Oppenheimer, a wealthy textile importer, who had emigrated to the United States from Germany in 1888, and Ella Friedman, a painter.
Oppenheimer had one brother, Frank, eight years younger, who also became a physicist.
The Oppenheimers were of Jewish descent but they did not practice or observe the religious
traditions.
Oppenheimer studied at the Ethical Culture Society School, founded
by Felix Adler to promote a form of ethical training based on the Ethical Culture movement. At the school, he studied mathematics and science, as well as subjects ranging
from Greek to French literature. Oppenheimer was a versatile scholar, interested in the humanities and in psychotherapy, as well as science. He entered Harvard
University one year late due to an attack of colitis. During the interim, he
went with a former English teacher to recuperate in New
Mexico, where he fell in love with horseback riding and the mountains and plateau of the
Southwest. At Harvard, he majored in chemistry, but also studied topics beyond science, including Greek, architecture, classics, art, and
literature. He made up for the delay caused by his illness, taking six courses each term and graduating summa cum laude in just three years. When at Harvard, Oppenheimer was admitted to graduate standing in
physics in his first year as an undergraduate on the basis of independent study. During a course on thermodynamics taught by Percy Bridgman, Oppenheimer was
introduced to experimental physics. In 1933 he learned Sanskrit and met the Indologist
Arthur W. Ryder at Berkeley, and read the Bhagavad Gita in
the original, citing it later as one of the most influential books to shape his philosophy of life.[2]
Europe
After graduating from Harvard, Oppenheimer was encouraged to go to Europe for future study, as
a world-class education in modern physics was not then available in the United States. He was accepted for postgraduate work at
Ernest Rutherford's famed Cavendish Laborajutory in
Cambridge, working under the eminent but aging J.J.
Thomson.
Oppenheimer's clumsiness in the laboratory made it apparent that his forte was theoretical, not experimental physics, so he
left in 1926 for the University of Göttingen to study under
Max Born. Göttingen was one of the top centers for theoretical physics in the world, and
Oppenheimer made a number of friends who would go on to great success, such as Werner
Heisenberg, Pascual Jordan, Wolfgang
Pauli, Paul Dirac, Enrico Fermi and
Edward Teller. At Göttingen, Oppenheimer was known for being a quick student.[3] However, he was also known for being too enthusiastic in
discussions, sometimes to the point of taking over seminar sessions, a fact that used to irritate a few of Born's pupils. In 1927
Oppenheimer obtained his Ph.D. at the young age of 22 at the University of
Göttingen, supervised by Max Born. After the oral exam for his Ph.D., the professor administering it is reported to have said,
"Phew, I'm glad that's over. He was on the point of questioning me."[4] At Göttingen, Oppenheimer published more than a dozen articles, including many important
contributions to the then newly developed quantum theory, most notably a famous paper
on the so-called Born-Oppenheimer approximation, which separates nuclear
motion from electronic motion in the mathematical treatment of molecules.
Early professional work
In September 1927, Oppenheimer returned to Harvard as a young maven of mathematical physics and a National Research Council Fellow, and in early 1928 he studied at the
California Institute of Technology.
While at Caltech he received numerous invitations for teaching positions, and accepted an assistant professorship in physics
at the University of California, Berkeley. In his words, "it was a
desert", yet paradoxically a fertile place of opportunity. He maintained a joint appointment with Caltech, where he spent every
spring term in order to avoid isolation from mainstream research. At Caltech, Oppenheimer struck a close friendship with
Linus Pauling and they planned to mount a joint attack on the nature of the chemical bond,
a field in which Pauling was a pioneer—apparently Oppenheimer would supply the mathematics and Pauling would interpret the
results. However, this collaboration, and their friendship, was nipped in the bud when Pauling began to suspect that the theorist
was becoming too close to his wife, Ava Helen.[5] Once when
Pauling was at work, Oppenheimer had come to their place and blurted out an invitation to Ava Helen to join him on a tryst in
Mexico. She flatly refused and reported this incident to Pauling. This, and her apparent
nonchalance about the incident, disquieted him, and he immediately cut off his relationship with the Berkeley professor. Later,
Oppenheimer invited Pauling to be the head of the Chemistry Division of the atomic bomb project, but Pauling refused, saying that
he was a pacifist.
In the autumn of 1928, Oppenheimer visited Paul Ehrenfest's institute at the
University of Leiden, the Netherlands, where he
impressed those there by giving lectures in Dutch despite having little experience with
the language. There he was given the nickname of "Opje," which was later Anglicized by his students as "Oppie". From Leiden he
continued on to Zurich, Switzerland to work with
Wolfgang Pauli on problems relating to quantum theory and the continuous spectrum, before
heading back to the United States. Oppenheimer highly respected and liked Pauli, and some of his own style and his critical
approach to problems was said to be inspired by Pauli. During his time with Ehrenfest and Pauli, Oppenheimer polished his
mathematical skills.
Before his Berkeley professorship began, Oppenheimer was diagnosed with a mild case of tuberculosis, and with his brother Frank, spent some weeks at a
ranch in New Mexico, which he leased and eventually purchased. When he heard the ranch was available for lease, he exclaimed,
"Hot dog!"—and later on the name of the ranch became "Perro Caliente," which is the translation of "hot dog" into
Spanish.[6] Later, Oppenheimer used to say that "physics
and desert country" were his "two great loves", loves that would be combined when he directed the atomic bomb project at Los
Alamos in New Mexico.[7]
He recovered from his tuberculosis and returned to Berkeley, where he prospered as an advisor and collaborator to a generation
of physicists who admired him for his intellectual virtuosity and broad interests. Nobel
Prize winner Hans Bethe later said about him:
| “ |
Probably the most important ingredient Oppenheimer brought to his teaching was his
exquisite taste. He always knew what were the important problems, as shown by his choice of subjects. He truly lived with those
problems, struggling for a solution, and he communicated his concern to the group.[8] |
” |
He also worked closely with (and became good friends with) Nobel Prize winning experimental physicist Ernest O. Lawrence and his cyclotron pioneers, helping the
experimentalists understand the data their machines were producing at the Lawrence's Radiation Laboratory.
Oppenheimer became known as a founding father of the American school of theoretical physics, and developed a reputation for
his erudition in physics, his eclecticism, his quick mind, his interest in languages and Eastern philosophy, and the eloquence
and clarity with which he thought. But he was also emotionally troubled throughout his life, and professed to experiencing
periods of depression. "I need physics more than friends," he once informed his brother.[9] A tall, thin chain smoker who often
neglected to eat during periods of intellectual discomfort and concentration, Oppenheimer was marked by many of his friends as
having a self-destructive tendency, and during numerous periods of his life worried his colleagues and associates with his
melancholy and insecurity. When he was studying in Cambridge and had taken a vacation to meet up with his friend Francis Ferguson
in Paris, a disturbing event had taken place. During a conversation in which Oppenheimer was narrating his frustration with
experimental physics to Ferguson, he had suddenly leapt up and tried to strangle him. Although Ferguson easily fended off the
attack, the episode had convinced Ferguson of his friend's deep psychological troubles.[10] Oppenheimer developed numerous affectations, seemingly in an attempt to convince
those around him—or possibly himself—of his self-worth. He was said to be mesmerizing, hypnotic in private interaction but often
frigid in more public settings. His associates fell into two camps: one that saw him as an aloof and impressive genius and an
aesthete; another that saw him as a pretentious and insecure poseur. His students almost always fell into the former category,
adopting "Oppie's" affectations, from his way of walking to talking and beyond—even trying to replicate his inclination for
reading entire texts in their originally transcribed languages.[11]
Scientific work
Oppenheimer's intelligence and charisma attracted students from across the country to Berkeley to study theoretical
physics.
Oppenheimer did important research in theoretical astrophysics
(especially as it relates to general relativity and nuclear theory), nuclear physics, spectroscopy, and quantum field theory (including its extension into quantum electrodynamics). The formalism of relativistic quantum mechanics also attracted his
attention, although because of the then existing well-known problem of the self-energy of
the electron, he doubted the validity of quantum electrodynamics at high energies. His best-known contribution, made as a
graduate student, is the Born-Oppenheimer approximation mentioned above.
He also made important contributions to the theory of cosmic ray showers and did work that
eventually led toward descriptions of quantum tunneling. His work on the
Oppenheimer-Phillips process, involved in artificial radioactivity under
bombardment by deuterons, has served as an important step in nuclear physics. In the late
1930s, he, along with the help of Hartland Snyder, was the first to write papers suggesting the existence of what we today call
black holes. In these papers, he demonstrated that there was a size limit (the so called
Tolman-Oppenheimer-Volkoff limit) to stars beyond which they would not
remain stable as neutron stars, and would undergo gravitational collapse. After the
Born-Oppenheimer approximation paper, these papers remain his most cited ones, and they were key in the rejuvenation of
astrophysical research in the United States in the 1950s, mainly by John Wheeler. As early
as 1930, he also wrote a paper essentially predicting the existence of the positron (which had
been postulated by Paul Dirac), a formulation that he however did not carry to its natural
outcome, because of his skepticism about the validity of the Dirac equation. As evidenced
above, his work predicts many later finds, which include, further, the neutron,
meson, and neutron star. Even beyond the immense
abstruseness of the topics he was expert in, Oppenheimer's papers were considered difficult to understand. Oppenheimer was very
fond of using elegant, if extremely complex, mathematical techniques to demonstrate physical principles though he was sometimes
criticized for making mathematical mistakes, presumably out of haste.
Many people thought that Oppenheimer's discoveries and research were not commensurate with his inherent abilities and talents.
They still considered him an outstanding physicist, but they did not place him at the very top rank of theorists who
fundamentally challenged the frontiers of knowledge.[12]
One reason for this could have been his diverse interests, which kept him from completely focusing on any individual topic for
long enough to bring it to full fruition. His close confidant and colleague, Nobel Prize winner Isidor Rabi, later gave his own interpretation:
| “ |
Oppenheimer was overeducated in those fields, which lie outside the scientific
tradition, such as his interest in religion, in the Hindu religion in particular, which resulted in a feeling of mystery of the
universe that surrounded him like a fog. He saw physics clearly, looking toward what had already been done, but at the border he
tended to feel there was much more of the mysterious and novel than there actually was...[he turned] away from the hard, crude
methods of theoretical physics into a mystical realm of broad intuition.[13] |
” |
In spite of this, some people (such as the Nobel Prize winner physicist Luis
Alvarez) have suggested that if he had lived long enough to see his predictions substantiated by experiment, Oppenheimer
might have won a Nobel Prize for his work on gravitational collapse, concerning
neutron stars and black holes.[14] In
retrospect, some physicists and historians consider this to be his most important contribution, though it was not taken up by
other scientists in his own lifetime.[15] Interestingly,
when the physicist and historian Abraham Pais once asked Oppenheimer about what he
considered to be his most important scientific contributions, Oppenheimer cited his work on electrons and positrons, but did not
mention anything about his work on gravitational contraction.[16]
Radical politics
During the 1920s, Oppenheimer kept himself aloof of worldly matters, and claimed not to have learned of the Stock Market Crash of 1929 until some time after the fact. Only when he became involved with
Jean Tatlock, the daughter of a Berkeley literature professor, in 1936, did he show any
interest in politics. Like many young intellectuals in the 1930s he became a supporter of social reforms which were later alleged
to be communist ideas. After inheriting over $300,000 upon his father's death in 1937, he
donated to many progressive efforts which were later branded as "left wing" during the "McCarthy" era. The majority of his
allegedly "radical" work consisted of hosting fund-raisers for the Republican
cause in the Spanish Civil War and other anti-fascist
activity. He never openly joined the Communist Party, though he did pass money to
so-called "liberal" causes by way of acquaintances who were alleged to be Party members.[17] Historian Gregg Herken has recently claimed to have evidence that Oppenheimer
did interact with the Communist Party during the 1930s and early 1940s.[18]
Oppenheimer’s brother Frank, Frank’s wife Jackie [19],
Oppenheimer’s own wife Kitty (widow of Communist political commissar Joe Dallet, killed in the Spanish Civil War) [20], his mistress, Jean Tatlock, and his landlady were all
active members of the Communist Party.[21]
In addition, several of Oppenheimer’s graduate students at Berkeley, including Joe Weinberg, Giovanni Rossi Lomanitz, David Bohm and Philip Morrison were Communist Party members [22]
Oppenheimer said he was “a member of just about every Communist Front organization on the West Coast,”[23][24] a subscriber to the People’s World,[25] a Communist Party organ, and, he testified, “I was associated with the Communist movement.”[26]
In 1937-42, in the midst of the Great Purge and Hitler-Stalin pact, Oppenheimer was a member at Berkeley of what he called a "discussion group,"
which was later identified by fellow members Haakon Chevalier[27][28] and Gordon Griffiths[29] as
a “closed” (secret) unit of the Communist Party for Berkeley faculty. If Oppenheimer was not a Communist, he was the only member
of this group who was not.[30]
Surveillance by the Federal Bureau of Investigation recorded that J.
Robert Oppenheimer attended a meeting in the home of self-proclaimed Communist Haakon
Chevalier with the Communist Party’s California state chairman William
Schneiderman and Isaac Folkoff, West Coast liaison between the Communist Party and
Soviet intelligence,in Fall 1940, during the Hitler-Stalin pact.[31]
Shortly thereafter, the FBI added Openheimer to its Custodial Detention Index,
listed as “Nationalistic Tendency: Communist.”[32]
A 1943 FBI report summarizing recent surveillance reported that Hannah Peters, organizer of the Doctor's Branch of the
Professional Section of the Communist Party, told Communist Party National Committee member Steve Nelson, the organizer for Alameda County, "that Dr. OPPIE, believed by the informant to be
J. ROBERT OPPENHEIMER ... could not be active in the Party at the present time." The report continued, reporting that Alameda
County Communist Party Secretary Bernadette Doyle proposed that the Alameda County Communist Party confer with the State
Committee of the Communist Party regarding "the two OPPIES, inasmuch as they were regularly registered (as members of the
Communist Party) and everyone in the county knew they were Communists. It is believed that the two OPPIES mentioned above had
reference to subject J. ROBERT OPPENHEIMER and his brother FRANK OPPENHEIMER."[33]
In a 1944 letter to Soviet Commissar for Internal Affairs Lavrenty Beria,
NKVD chief Boris Merkulov reported:
| “ |
In 1942 one of the leaders of scientific work on uranium in the USA, Professor
Oppenheimer while being an unlisted [nglastny] member of the apparatus of [American Communist Party Secretary]
Comrade Browder informed us about the beginning of work. On the request of [NKVD San
Francisco station chief] Comrade [Grigoriy] Kheifitz,[34]
confirmed by Comrade Browder, he provided cooperation in access to research for several of our tested sources including a
relative of Comrade Browder.[35] |
” |
Merkulov added:
| “ |
Due to complications of the operational situation in the USA, dissolution of the
Comintern and explanations of Comrades Zarubin and
Kheifitz on the Mironov affair it is expedient to immediately sever contacts of leaders and activists of the American Communist
Party with scientists and specialists engaged in work on uranium.[36] |
” |
Many debates over Oppenheimer's Party membership or lack thereof have turned on very fine points; almost all historians agree
he had strong socially progressive sympathies during this time, and interacted with Party members, though there is considerable
dispute over whether he was officially a member of the Party or not.[37]
Frank Oppenheimer and some of his graduate students were Party members at different times.[38]
Marriage and family life
In November 1940, Oppenheimer married Katherine ("Kitty") Puening Harrison, a radical Berkeley student and former Communist
Party member. Harrison had been married twice previously, first to Joe Dallet, a Communist Party and union activist who was
killed in the Spanish civil war. She divorced her second husband, a southern California doctor, to marry Oppenheimer.
By May 1941 they had their first child, Peter. Their second child, Katherine (called Toni), was born in 1944, while
Oppenheimer was scientific director of the Manhattan Project.
During his marriage, Oppenheimer continued his involvement with Jean Tatlock, though it
is not clear if they continued their love affair.[39]
Later their continued contact became an issue in Oppenheimer's security clearance hearings, due to Tatlock's communist
associations.
The Manhattan Project
-
When World War II started, Oppenheimer became involved in the efforts to develop an
atomic bomb, which were already taking up much of the time and facilities of Lawrence's
Radiation Laboratory at Berkeley. In 1941, Lawrence, Vannevar Bush, Arthur Compton, and James Conant worked to wrest the bomb project from the S-1 Uranium
Committee, because they felt it was proceeding too slowly. Oppenheimer was invited to take over work on fast neutron
calculations, a task that he threw himself into with full vigor. At this time he renounced what he called his "left-wing
wanderings" to concentrate on his responsibilities, though he continued to maintain friendships with many who were quite
radical.
In 1942, the U.S. Army was given jurisdiction over the bomb effort, which was
renamed as the Manhattan Engineering District, or Manhattan Project. General Leslie R.
Groves was appointed project director, and Groves, in turn, selected Oppenheimer as the project's scientific director.
Groves knew Oppenheimer would be viewed as a security risk, but thought that Oppenheimer was the best man to direct a diverse
team of scientists and would be unaffected by his past political leanings.
Los Alamos
One of Oppenheimer's first acts was to host a summer school for bomb theory at his building in Berkeley. The mix of European
physicists and his own students—a group including Robert Serber, Emil Konopinski, Felix Bloch, Hans
Bethe, and Edward Teller—busied themselves calculating what needed to be done, and
in what order, to make the bomb. Teller put forward the remote possibility that the bomb would generate enough heat to ignite the
atmosphere. While such an event was soon shown to be impossible by Bethe, Oppenheimer nevertheless was concerned enough to meet
up with Arthur Compton in Michigan to discuss the
situation. At the time, research for the project was going on at many different universities and laboratories across the country,
presenting a problem for both security and cohesion. Oppenheimer and Groves decided that they needed a centralized, secret
research laboratory. Scouting for a site, Oppenheimer was drawn to New Mexico, not far from his ranch. On a flat mesa near Santa Fe, New Mexico, the Los Alamos laboratory was hastily built on the site of a private boys' school. There
Oppenheimer assembled a group of the top physicists of the time, which he referred to as the "luminaries",[40] including Enrico Fermi,
Richard Feynman, Robert R. Wilson, and
Victor Weisskopf, as well as Bethe and Teller.
Oppenheimer was noted for his mastery of all scientific aspects of the project and for his efforts to control the inevitable
cultural conflicts between scientists and the military. He was an iconic figure to his fellow scientists, as much a figurehead of
what they were working towards as a scientific director. Victor Weisskopf put it thus:
| “ |
He did not direct from the head office. He was intellectually and even physically
present at each decisive step. He was present in the laboratory or in the seminar rooms, when a new effect was measured, when a
new idea was conceived. It was not that he contributed so many ideas or suggestions; he did so sometimes, but his main influence
came from something else. It was his continuous and intense presence, which produced a sense of direct participation in all of
us; it created that unique atmosphere of enthusiasm and challenge that pervaded the place throughout its time.[8] |
” |
All the while, Oppenheimer was under investigation by both the FBI
and the Manhattan Project's internal security arm for his past left-wing associations. He was also followed by Army security
agents during an unannounced trip to California in 1943 to meet his former
girlfriend, Jean Tatlock.[41] In August 1943, Oppenheimer
told Manhattan Project security agents that three of his students had been solicited for nuclear secrets by a friend of his with
Communist connections. When pressed on the issue in later interviews with General Groves and security agents, he identified the
friend as Haakon Chevalier, a Berkeley professor of French literature. Oppenheimer
would be asked for interviews related to the "Chevalier incident", and he often gave contradictory and equivocating statements,
telling Groves that only one person had actually been approached, and that person was his brother Frank. But Groves still thought
Oppenheimer too important to the ultimate Allied goals to oust him over this suspicious behavior—he was, Groves reported,
"absolutely essential to the project".[42]
Trinity
-
- See also: Bhagavad Gita#Influence of the Bhagavad
Gita and Trinity test#The explosion
The joint work of the scientists at Los Alamos resulted in the first nuclear
explosion near Alamogordo on July 16,
1945, the site of which Oppenheimer named "Trinity",
Oppenheimer later said this name was from one of John Donne's Holy Sonnets. According to the historian Gregg Herken, this naming could have been an allusion to Jean Tatlock, who
had committed suicide a few months previously, and had in the 1930s introduced Oppenheimer to Donne's work.[43] Oppenheimer later recalled that while witnessing the explosion he thought
of a verse from the Hindu holy book, the Bhagavad
Gita:
| “ |
If the radiance of a thousand suns were to burst at once into the sky, that would be
like the splendor of the mighty one... |
” |
Years later he would explain that another verse had also entered his head at that time:
It is the famous verse, which begins as "Kalo Asmi" and was quoted by Oppenheimer after the successful detonation of the first
nuclear weapon. He unfortunately mistranslated it as "Now I am become Death, the destroyer of worlds". The correct meaning of the
Sanskrit words is "Now I am Time (not death), the destroyer of all."
| “ |
We knew the world would not be the same. A few people laughed, a few people cried,
most people were silent. I remembered the line from the Hindu scripture, the Bhagavad-Gita. Vishnu is trying to persuade the Prince that he should do his duty and to impress him takes on his multi-armed form and says, 'Now, I am become
Death, the destroyer of worlds.' I suppose we all thought that one way or another.'[44] |
” |
According to his brother, at the time Oppenheimer simply exclaimed, "It worked." News of the successful test was rushed to
President Harry S. Truman, who authorized the atomic bombings of Hiroshima and Nagasaki, Japan. Oppenheimer later became an
important figure in the debates on the repercussions of this act.
Postwar activities
Overnight, Oppenheimer became a national spokesman for science, and emblematic of a new type of technocratic power. Nuclear
physics became a powerful force as all governments of the world began to realize the strategic and political power that came with
nuclear weapons and their horrific implications. Like many scientists of his generation, he felt that security from atomic bombs
would come only from some form of transnational organization (such as the newly formed United
Nations), which could institute a program to stifle a nuclear arms race.
Atomic Energy Commission
After the Atomic Energy Commission (AEC) was created in 194
