Robert Oppenheimer

# Robert Oppenheimer

Overview
Julius Robert Oppenheimer (April 22, 1904 – February 18, 1967) was an American theoretical physicist
Theoretical physics
Theoretical physics is a branch of physics which employs mathematical models and abstractions of physics to rationalize, explain and predict natural phenomena...

and professor of physics at the University of California, Berkeley
University of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...

. Along with Enrico Fermi
Enrico Fermi
Enrico Fermi was an Italian-born, naturalized American physicist particularly known for his work on the development of the first nuclear reactor, Chicago Pile-1, and for his contributions to the development of quantum theory, nuclear and particle physics, and statistical mechanics...

, he is often called the "father of the atomic bomb" for his role in the Manhattan Project
Manhattan Project
The Manhattan Project was a research and development program, led by the United States with participation from the United Kingdom and Canada, that produced the first atomic bomb during World War II. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the US Army...

, the World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

project that developed the first nuclear weapon
Nuclear weapon
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion. Both reactions release vast quantities of energy from relatively small amounts of matter. The first fission bomb test released the same amount...

s. The first atomic bomb was detonated on July 16, 1945 in the Trinity test
Trinity test
Trinity was the code name of the first test of a nuclear weapon. This test was conducted by the United States Army on July 16, 1945, in the Jornada del Muerto desert about 35 miles southeast of Socorro, New Mexico, at the new White Sands Proving Ground, which incorporated the Alamogordo Bombing...

in New Mexico
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...

; Oppenheimer remarked later that it brought to mind words from the Bhagavad Gita
The ' , also more simply known as Gita, is a 700-verse Hindu scripture that is part of the ancient Sanskrit epic, the Mahabharata, but is frequently treated as a freestanding text, and in particular, as an Upanishad in its own right, one of the several books that constitute general Vedic tradition...

: "Now, I am become Death, the destroyer of worlds."

After the war he became a chief adviser to the newly created United States Atomic Energy Commission
United States Atomic Energy Commission
The United States Atomic Energy Commission was an agency of the United States government established after World War II by Congress to foster and control the peace time development of atomic science and technology. President Harry S...

and used that position to lobby for international control of nuclear power
Nuclear power
Nuclear power is the use of sustained nuclear fission to generate heat and electricity. Nuclear power plants provide about 6% of the world's energy and 13–14% of the world's electricity, with the U.S., France, and Japan together accounting for about 50% of nuclear generated electricity...

to avert nuclear proliferation
Nuclear proliferation
Nuclear proliferation is a term now used to describe the spread of nuclear weapons, fissile material, and weapons-applicable nuclear technology and information, to nations which are not recognized as "Nuclear Weapon States" by the Treaty on the Nonproliferation of Nuclear Weapons, also known as the...

and an arms race
Nuclear arms race
The nuclear arms race was a competition for supremacy in nuclear warfare between the United States, the Soviet Union, and their respective allies during the Cold War...

with the Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

.
Discussion

Quotations

I can't think that it would be terrible of me to say — and it is occasionally true — that I need physics more than friends.

Letter to his brother Frank Oppenheimer|Frank Oppenheimer (14 October 1929), published in Robert Oppenheimer : Letters and Recollections (1995) edited by Alice Kimball Smith, p. 135

It worked.

His exclamation after the Trinity test|Trinity atomic bomb test (16 July 1945), according to his brother in the documentary The Day After Trinity

The open society, the unrestricted access to knowledge, the unplanned and uninhibited association of men for its furtherance — these are what may make a vast, complex, ever growing, ever changing, ever more specialized and expert technological world, nevertheless a world of human community.

Science and the Common Understanding (1953)

It's not that I don't feel bad about it. It's just that I don't feel worse today than what I felt yesterday.

Response to question on his feelings about the atomic bombings, while visiting Japan in 1960.
Encyclopedia
Julius Robert Oppenheimer (April 22, 1904 – February 18, 1967) was an American theoretical physicist
Theoretical physics
Theoretical physics is a branch of physics which employs mathematical models and abstractions of physics to rationalize, explain and predict natural phenomena...

and professor of physics at the University of California, Berkeley
University of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...

. Along with Enrico Fermi
Enrico Fermi
Enrico Fermi was an Italian-born, naturalized American physicist particularly known for his work on the development of the first nuclear reactor, Chicago Pile-1, and for his contributions to the development of quantum theory, nuclear and particle physics, and statistical mechanics...

, he is often called the "father of the atomic bomb" for his role in the Manhattan Project
Manhattan Project
The Manhattan Project was a research and development program, led by the United States with participation from the United Kingdom and Canada, that produced the first atomic bomb during World War II. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the US Army...

, the World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

project that developed the first nuclear weapon
Nuclear weapon
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion. Both reactions release vast quantities of energy from relatively small amounts of matter. The first fission bomb test released the same amount...

s. The first atomic bomb was detonated on July 16, 1945 in the Trinity test
Trinity test
Trinity was the code name of the first test of a nuclear weapon. This test was conducted by the United States Army on July 16, 1945, in the Jornada del Muerto desert about 35 miles southeast of Socorro, New Mexico, at the new White Sands Proving Ground, which incorporated the Alamogordo Bombing...

in New Mexico
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...

; Oppenheimer remarked later that it brought to mind words from the Bhagavad Gita
The ' , also more simply known as Gita, is a 700-verse Hindu scripture that is part of the ancient Sanskrit epic, the Mahabharata, but is frequently treated as a freestanding text, and in particular, as an Upanishad in its own right, one of the several books that constitute general Vedic tradition...

: "Now, I am become Death, the destroyer of worlds."

After the war he became a chief adviser to the newly created United States Atomic Energy Commission
United States Atomic Energy Commission
The United States Atomic Energy Commission was an agency of the United States government established after World War II by Congress to foster and control the peace time development of atomic science and technology. President Harry S...

and used that position to lobby for international control of nuclear power
Nuclear power
Nuclear power is the use of sustained nuclear fission to generate heat and electricity. Nuclear power plants provide about 6% of the world's energy and 13–14% of the world's electricity, with the U.S., France, and Japan together accounting for about 50% of nuclear generated electricity...

to avert nuclear proliferation
Nuclear proliferation
Nuclear proliferation is a term now used to describe the spread of nuclear weapons, fissile material, and weapons-applicable nuclear technology and information, to nations which are not recognized as "Nuclear Weapon States" by the Treaty on the Nonproliferation of Nuclear Weapons, also known as the...

and an arms race
Nuclear arms race
The nuclear arms race was a competition for supremacy in nuclear warfare between the United States, the Soviet Union, and their respective allies during the Cold War...

with the Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

. After provoking the ire of many politicians with his outspoken opinions during the Second Red Scare, he had his security clearance revoked in a much-publicized hearing in 1954, and was effectively stripped of his direct political influence; he continued to lecture, write and work in physics. A decade later President John F. Kennedy
John F. Kennedy
John Fitzgerald "Jack" Kennedy , often referred to by his initials JFK, was the 35th President of the United States, serving from 1961 until his assassination in 1963....

awarded (and Lyndon B. Johnson
Lyndon B. Johnson
Lyndon Baines Johnson , often referred to as LBJ, was the 36th President of the United States after his service as the 37th Vice President of the United States...

presented) him with the Enrico Fermi Award
Enrico Fermi Award
The Enrico Fermi Award is an award honoring scientists of international stature for their lifetime achievement in the development, use, or production of energy. It is administered by the U.S. government's Department of Energy...

as a gesture of political rehabilitation
Political rehabilitation
Political rehabilitation is the process by which a member of a political organization or government who has fallen into disgrace, is restored to public life. It is usually applied to leaders or other prominent individuals who regain their prominence after a period in which they have no influence or...

.

Oppenheimer's notable achievements in physics include the Born–Oppenheimer approximation for molecular wavefunction
Wavefunction
Not to be confused with the related concept of the Wave equationA wave function or wavefunction is a probability amplitude in quantum mechanics describing the quantum state of a particle and how it behaves. Typically, its values are complex numbers and, for a single particle, it is a function of...

s, work on the theory of electron
Electron
The electron is a subatomic particle with a negative elementary electric charge. It has no known components or substructure; in other words, it is generally thought to be an elementary particle. An electron has a mass that is approximately 1/1836 that of the proton...

s and positron
Positron
The positron or antielectron is the antiparticle or the antimatter counterpart of the electron. The positron has an electric charge of +1e, a spin of ½, and has the same mass as an electron...

s, the Oppenheimer–Phillips process in nuclear fusion
Nuclear fusion
Nuclear fusion is the process by which two or more atomic nuclei join together, or "fuse", to form a single heavier nucleus. This is usually accompanied by the release or absorption of large quantities of energy...

, and the first prediction of quantum tunneling. With his students he also made important contributions to the modern theory of neutron star
Neutron star
A neutron star is a type of stellar remnant that can result from the gravitational collapse of a massive star during a Type II, Type Ib or Type Ic supernova event. Such stars are composed almost entirely of neutrons, which are subatomic particles without electrical charge and with a slightly larger...

s and black hole
Black hole
A black hole is a region of spacetime from which nothing, not even light, can escape. The theory of general relativity predicts that a sufficiently compact mass will deform spacetime to form a black hole. Around a black hole there is a mathematically defined surface called an event horizon that...

s, as well as to quantum mechanics
Quantum mechanics
Quantum mechanics, also known as quantum physics or quantum theory, is a branch of physics providing a mathematical description of much of the dual particle-like and wave-like behavior and interactions of energy and matter. It departs from classical mechanics primarily at the atomic and subatomic...

, quantum field theory
Quantum field theory
Quantum field theory provides a theoretical framework for constructing quantum mechanical models of systems classically parametrized by an infinite number of dynamical degrees of freedom, that is, fields and many-body systems. It is the natural and quantitative language of particle physics and...

, and the interactions of cosmic ray
Cosmic ray
Cosmic rays are energetic charged subatomic particles, originating from outer space. They may produce secondary particles that penetrate the Earth's atmosphere and surface. The term ray is historical as cosmic rays were thought to be electromagnetic radiation...

s. As a teacher and promoter of science, he is remembered as a founding father of the American school of theoretical physics that gained world prominence in the 1930s. After World War II, he became director of the Institute for Advanced Study
The Institute for Advanced Study, located in Princeton, New Jersey, United States, is an independent postgraduate center for theoretical research and intellectual inquiry. It was founded in 1930 by Abraham Flexner...

in Princeton.

### Childhood and education

Oppenheimer was born in New York City on April 22, 1904, to Julius S. Oppenheimer, a wealthy Jewish textile importer who had immigrated to the United States from Germany in 1888, and Ella Friedman, a painter. In 1912 the family moved to an apartment on the eleventh floor of 155 Riverside Drive
Riverside Drive (Manhattan)
Riverside Drive is a scenic north-south thoroughfare in the Manhattan borough of New York City. The boulevard runs on the west side of Manhattan, generally parallel to the Hudson River from 72nd Street to near the George Washington Bridge at 181st Street...

, near West 88th Street, Manhattan
Manhattan
Manhattan is the oldest and the most densely populated of the five boroughs of New York City. Located primarily on the island of Manhattan at the mouth of the Hudson River, the boundaries of the borough are identical to those of New York County, an original county of the state of New York...

, an area known for luxurious mansions and town houses. Their art collection included works by Pablo Picasso
Pablo Picasso
Pablo Diego José Francisco de Paula Juan Nepomuceno María de los Remedios Cipriano de la Santísima Trinidad Ruiz y Picasso known as Pablo Ruiz Picasso was a Spanish expatriate painter, sculptor, printmaker, ceramicist, and stage designer, one of the greatest and most influential artists of the...

and Édouard Vuillard
Édouard Vuillard
Jean-Édouard Vuillard was a French painter and printmaker associated with the Nabis.-Early years and education:...

, and at least three original paintings by Vincent van Gogh
Vincent van Gogh
Vincent Willem van Gogh , and used Brabant dialect in his writing; it is therefore likely that he himself pronounced his name with a Brabant accent: , with a voiced V and palatalized G and gh. In France, where much of his work was produced, it is...

. Robert had a younger brother, Frank
Frank Oppenheimer
Frank Friedman Oppenheimer was an American physicist who worked on the Manhattan Project, was a target of McCarthyism, and was later the founder of the Exploratorium in San Francisco. He was the younger brother of J...

, who also became a physicist.

Oppenheimer was initially schooled at Alcuin Preparatory School, and in 1911 entered the Ethical Culture Society School
Ethical Culture Fieldston School
The Ethical Culture Fieldston School, known as "Fieldston", is a private "independent" school in New York City and a member of the Ivy Preparatory School League. It has about 1600 students and a staff of 400 people , led by Dr. Damian J...

. This had been founded by Felix Adler to promote a form of ethical training based on the Ethical Culture
Ethical Culture
The Ethical movement, also referred to as the Ethical Culture movement or simply Ethical Culture, is an ethical, educational, and religious movement that is usually traced back to Felix Adler...

movement, whose motto was "Deed before Creed". His father had been a member of the Society for many years, serving on its board of trustees from 1907 to 1915. Oppenheimer was a versatile scholar, interested in English and French literature, and particularly in mineralogy
Mineralogy
Mineralogy is the study of chemistry, crystal structure, and physical properties of minerals. Specific studies within mineralogy include the processes of mineral origin and formation, classification of minerals, their geographical distribution, as well as their utilization.-History:Early writing...

. He completed the third and fourth grades in one year, and skipped half the eighth grade. During his final year, he became interested in chemistry. He entered Harvard College
Harvard College
Harvard College, in Cambridge, Massachusetts, is one of two schools within Harvard University granting undergraduate degrees...

a year late, at age 18, because he suffered an attack of colitis
Ulcerative colitis
Ulcerative colitis is a form of inflammatory bowel disease . Ulcerative colitis is a form of colitis, a disease of the colon , that includes characteristic ulcers, or open sores. The main symptom of active disease is usually constant diarrhea mixed with blood, of gradual onset...

while prospecting
Prospecting
Prospecting is the physical search for minerals, fossils, precious metals or mineral specimens, and is also known as fossicking.Prospecting is a small-scale form of mineral exploration which is an organised, large scale effort undertaken by mineral resource companies to find commercially viable ore...

in Joachimstal during a family summer vacation in Europe. To help him recover from the illness, his father enlisted the help of his English teacher Herbert Smith who took him to New Mexico, where Oppenheimer fell in love with horseback riding and the southwestern United States.

In addition to majoring in chemistry, he was also required by Harvard's rules to study history, literature, and philosophy or mathematics. He made up for his late start by taking six courses each term and was admitted to the undergraduate honor society
Honor society
In the United States, an honor society is a rank organization that recognizes excellence among peers. Numerous societies recognize various fields and circumstances. The Order of the Arrow, for example, is the national honor society of the Boy Scouts of America...

Phi Beta Kappa. In his first year he was admitted to graduate standing in physics on the basis of independent study, which meant he was not required to take the basic classes and could enroll instead in advanced ones. A course on thermodynamics
Thermodynamics
Thermodynamics is a physical science that studies the effects on material bodies, and on radiation in regions of space, of transfer of heat and of work done on or by the bodies or radiation...

taught by Percy Bridgman
Percy Williams Bridgman
Percy Williams Bridgman was an American physicist who won the 1946 Nobel Prize in Physics for his work on the physics of high pressures. He also wrote extensively on the scientific method and on other aspects of the philosophy of science.- Biography :Bridgman entered Harvard University in 1900,...

attracted him to experimental physics. He graduated summa cum laude in three years.

### Studies in Europe

In 1924 Oppenheimer was informed that he had been accepted into Christ's College, Cambridge
Christ's College, Cambridge
Christ's College is a constituent college of the University of Cambridge.With a reputation for high academic standards, Christ's College averaged top place in the Tompkins Table from 1980-2000 . In 2011, Christ's was placed sixth.-College history:...

. He wrote to Ernest Rutherford
Ernest Rutherford
Ernest Rutherford, 1st Baron Rutherford of Nelson OM, FRS was a New Zealand-born British chemist and physicist who became known as the father of nuclear physics...

requesting permission to work at the Cavendish Laboratory
Cavendish Laboratory
The Cavendish Laboratory is the Department of Physics at the University of Cambridge, and is part of the university's School of Physical Sciences. It was opened in 1874 as a teaching laboratory....

. Bridgman provided Oppenheimer with a recommendation, which conceded that Oppenheimer's clumsiness in the laboratory made it apparent his forte was not experimental but rather theoretical physics. Rutherford was unimpressed, but Oppenheimer went to Cambridge in the hope of landing another offer. He was ultimately accepted by J. J. Thomson
J. J. Thomson
Sir Joseph John "J. J." Thomson, OM, FRS was a British physicist and Nobel laureate. He is credited for the discovery of the electron and of isotopes, and the invention of the mass spectrometer...

on condition that he complete a basic laboratory course. He developed an antagonistic relationship with his tutor, Patrick Blackett
Patrick Blackett, Baron Blackett
Patrick Maynard Stuart Blackett, Baron Blackett OM CH FRS was an English experimental physicist known for his work on cloud chambers, cosmic rays, and paleomagnetism. He also made a major contribution in World War II advising on military strategy and developing Operational Research...

, who was only a few years his senior. While on vacation, as recalled by his friend Francis Ferguson, Oppenheimer once confessed that he had left an apple doused with noxious chemicals on Blackett's desk. While Ferguson's account is the only detailed version of this event, Oppenheimer's parents were alerted by the university authorities who considered placing him on probation, a fate prevented by his parents successfully lobbying the authorities.

A tall, thin chain smoker
Chain smoking
Chain smoking is the practice of lighting a new cigarette for personal consumption immediately after one that is finished, sometimes using the finished cigarette to light the next one. It is a common form of addiction.-Causes:...

, who often neglected to eat during periods of intense thought and concentration, Oppenheimer was marked by many of his friends as having self-destructive tendencies. A disturbing event occurred when he took a vacation from his studies in Cambridge to meet up with his friend Francis Ferguson in Paris. During a conversation in which Oppenheimer was explaining his frustration with experimental physics, he suddenly leapt up and tried to strangle Ferguson. Although Ferguson easily fended off the attack, the episode convinced him of Oppenheimer's deep psychological troubles. Plagued throughout his life by periods of depression, Oppenheimer once told his brother, "I need physics more than friends".

In 1926 he left Cambridge for the University of Göttingen to study under Max Born
Max Born
Max Born was a German-born physicist and mathematician who was instrumental in the development of quantum mechanics. He also made contributions to solid-state physics and optics and supervised the work of a number of notable physicists in the 1920s and 30s...

. Göttingen was one of the world's leading centers for theoretical physics. Oppenheimer made friends who went on to great success, including Werner Heisenberg
Werner Heisenberg
Werner Karl Heisenberg was a German theoretical physicist who made foundational contributions to quantum mechanics and is best known for asserting the uncertainty principle of quantum theory...

, Pascual Jordan
Pascual Jordan

, Wolfgang Pauli
Wolfgang Pauli
Wolfgang Ernst Pauli was an Austrian theoretical physicist and one of the pioneers of quantum physics. In 1945, after being nominated by Albert Einstein, he received the Nobel Prize in Physics for his "decisive contribution through his discovery of a new law of Nature, the exclusion principle or...

, Paul Dirac
Paul Dirac
Paul Adrien Maurice Dirac, OM, FRS was an English theoretical physicist who made fundamental contributions to the early development of both quantum mechanics and quantum electrodynamics...

, Enrico Fermi
Enrico Fermi
Enrico Fermi was an Italian-born, naturalized American physicist particularly known for his work on the development of the first nuclear reactor, Chicago Pile-1, and for his contributions to the development of quantum theory, nuclear and particle physics, and statistical mechanics...

and Edward Teller
Edward Teller
Edward Teller was a Hungarian-American theoretical physicist, known colloquially as "the father of the hydrogen bomb," even though he did not care for the title. Teller made numerous contributions to nuclear and molecular physics, spectroscopy , and surface physics...

. He was known for being too enthusiastic in discussion, sometimes to the point of taking over seminar sessions. This irritated some of Born's other students so much that Maria Goeppert presented Born with a petition signed by herself and others threatening a boycott of the class unless he made Oppenheimer quiet down. Born left it out on his desk where Oppenheimer could read it, and it was effective without a word being said.

He obtained his Doctor of Philosophy degree in March 1927 at age 23, supervised by Born. After the oral exam, James Franck
James Franck
James Franck was a German Jewish physicist and Nobel laureate.-Biography:Franck was born to Jacob Franck and Rebecca Nachum Drucker. Franck completed his Ph.D...

, the professor administering, reportedly said, "I'm glad that's over. He was on the point of questioning me." Oppenheimer published more than a dozen papers at Göttingen, including many important contributions to the new field of quantum mechanics. He and Born published a famous paper on the Born-Oppenheimer approximation
Born-Oppenheimer approximation
In quantum chemistry, the computation of the energy and wavefunction of an average-size molecule is a formidable task that is alleviated by the Born–Oppenheimer approximation, named after Max Born and J. Robert Oppenheimer. For instance the benzene molecule consists of 12 nuclei and 42...

, which separates nuclear motion from electronic motion in the mathematical treatment of molecules, allowing nuclear motion to be neglected to simplify calculations. It remains his most cited work.

### Educational work

Oppenheimer was awarded a United States National Research Council
United States National Research Council
The National Research Council of the USA is the working arm of the United States National Academies, carrying out most of the studies done in their names.The National Academies include:* National Academy of Sciences...

fellowship to the California Institute of Technology
California Institute of Technology
The California Institute of Technology is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering...

(Caltech) in September 1927. Bridgman also wanted him at Harvard, so a compromise was reached whereby he split his fellowship for the 1927–28 academic year between Harvard in 1927 and Caltech in 1928. At Caltech he struck up a close friendship with Linus Pauling
Linus Pauling
Linus Carl Pauling was an American chemist, biochemist, peace activist, author, and educator. He was one of the most influential chemists in history and ranks among the most important scientists of the 20th century...

, and they planned to mount a joint attack on the nature of the chemical bond, a field in which Pauling was a pioneer, with Oppenheimer supplying the mathematics and Pauling interpreting the results. Both the collaboration and their friendship were nipped in the bud when Pauling began to suspect Oppenheimer of becoming too close to his wife, Ava Helen Pauling
Ava Helen Pauling
Ava Helen Pauling was an American human rights activist and wife of Nobel Prize winner Linus Pauling. Throughout her life, she was involved in various social movements including women's rights, racial equality, and international peace.An avid New Dealer, Ava Helen Pauling was heavily interested...

. Once, when Pauling was at work, Oppenheimer had arrived at their home and invited Ava Helen to join him on a tryst in Mexico, though she refused and reported the incident to her husband. The invitation, and her apparent nonchalance about it, disquieted Pauling, and he ended his relationship with Oppenheimer. Oppenheimer later invited him to become head of the Chemistry Division of the Manhattan Project
Manhattan Project
The Manhattan Project was a research and development program, led by the United States with participation from the United Kingdom and Canada, that produced the first atomic bomb during World War II. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the US Army...

, but Pauling refused, saying he was a pacifist.

In the autumn of 1928, Oppenheimer visited Paul Ehrenfest
Paul Ehrenfest
Paul Ehrenfest was an Austrian and Dutch physicist, who made major contributions to the field of statistical mechanics and its relations with quantum mechanics, including the theory of phase transition and the Ehrenfest theorem.- Biography :Paul Ehrenfest was born and grew up in Vienna in a Jewish...

's institute at the University of Leiden, the Netherlands, where he impressed them by giving lectures in Dutch, despite having little experience with the language. There he was given the nickname of Opje, later Anglicized by his students as "Oppie". From Leiden he continued on to the ETH
Eth
Eth is a letter used in Old English, Icelandic, Faroese , and Elfdalian. It was also used in Scandinavia during the Middle Ages, but was subsequently replaced with dh and later d. The capital eth resembles a D with a line through the vertical stroke...

in Zurich to work with Wolfgang Pauli
Wolfgang Pauli
Wolfgang Ernst Pauli was an Austrian theoretical physicist and one of the pioneers of quantum physics. In 1945, after being nominated by Albert Einstein, he received the Nobel Prize in Physics for his "decisive contribution through his discovery of a new law of Nature, the exclusion principle or...

on quantum mechanics
Quantum mechanics
Quantum mechanics, also known as quantum physics or quantum theory, is a branch of physics providing a mathematical description of much of the dual particle-like and wave-like behavior and interactions of energy and matter. It departs from classical mechanics primarily at the atomic and subatomic...

and the continuous spectrum
Continuous spectrum
The spectrum of a linear operator is commonly divided into three parts: point spectrum, continuous spectrum, and residual spectrum.If H is a topological vector space and A:H \to H is a linear map, the spectrum of A is the set of complex numbers \lambda such that A - \lambda I : H \to H is not...

. Oppenheimer respected and liked Pauli, who may have inspired some of Oppenheimer's own style and his critical approach to problems.

On returning to the United States, Oppenheimer accepted an associate professorship from the University of California, Berkeley
University of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...

, where Raymond T. Birge wanted him badly enough to offer to share him with Caltech. Before his Berkeley professorship began, Oppenheimer was diagnosed with a mild case of tuberculosis
Tuberculosis
Tuberculosis, MTB, or TB is a common, and in many cases lethal, infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis. Tuberculosis usually attacks the lungs but can also affect other parts of the body...

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 called it Perro Caliente, literally "hot dog" in Spanish. Later he used to say that "physics and desert country" were his "two great loves". He recovered from the tuberculosis and returned to Berkeley, where he prospered as an adviser and collaborator to a generation of physicists who admired him for his intellectual virtuosity and broad interests. His students and colleagues saw him as 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 aesthete, the other that saw him as a pretentious and insecure poseur. His students almost always fell into the former category, adopting his walk, speech, and other mannerisms, and even his inclination for reading entire texts in their original languages. Hans Bethe
Hans Bethe
Hans Albrecht Bethe was a German-American nuclear physicist, and Nobel laureate in physics for his work on the theory of stellar nucleosynthesis. A versatile theoretical physicist, Bethe also made important contributions to quantum electrodynamics, nuclear physics, solid-state physics and...

said of him:
He worked closely with Nobel Prize
Nobel Prize in Physics
The Nobel Prize in Physics is awarded once a year by the Royal Swedish Academy of Sciences. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901; the others are the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and...

-winning experimental physicist Ernest O. Lawrence and his cyclotron
Cyclotron
In technology, a cyclotron is a type of particle accelerator. In physics, the cyclotron frequency or gyrofrequency is the frequency of a charged particle moving perpendicularly to the direction of a uniform magnetic field, i.e. a magnetic field of constant magnitude and direction...

pioneers, helping them understand the data their machines were producing at the Lawrence Berkeley National Laboratory
Lawrence Berkeley National Laboratory
The Lawrence Berkeley National Laboratory , is a U.S. Department of Energy national laboratory conducting unclassified scientific research. It is located on the grounds of the University of California, Berkeley, in the Berkeley Hills above the central campus...

. In 1936 Berkeley promoted him to full professor at a salary of $3,300 per annum. In return he was asked to curtail his teaching at Caltech, so a compromise was reached whereby Berkeley released him for six weeks each year, enough to teach one term at Caltech. ### Scientific work Oppenheimer did important research in theoretical astronomy Theoretical astronomy Based on strict dictionary definitions, "astronomy" refers to "the study of objects and matter outside the Earth's atmosphere and of their physical and chemical properties" In some cases, as in the introduction of the introductory textbook The Physical Universe by Frank Shu, "astronomy" may be used... (especially as related to general relativity General relativity General relativity or the general theory of relativity is the geometric theory of gravitation published by Albert Einstein in 1916. It is the current description of gravitation in modern physics... and nuclear theory), nuclear physics Nuclear physics Nuclear physics is the field of physics that studies the building blocks and interactions of atomic nuclei. The most commonly known applications of nuclear physics are nuclear power generation and nuclear weapons technology, but the research has provided application in many fields, including those... , spectroscopy Spectroscopy Spectroscopy is the study of the interaction between matter and radiated energy. Historically, spectroscopy originated through the study of visible light dispersed according to its wavelength, e.g., by a prism. Later the concept was expanded greatly to comprise any interaction with radiative... , and quantum field theory Quantum field theory Quantum field theory provides a theoretical framework for constructing quantum mechanical models of systems classically parametrized by an infinite number of dynamical degrees of freedom, that is, fields and many-body systems. It is the natural and quantitative language of particle physics and... , including its extension into quantum electrodynamics Quantum electrodynamics Quantum electrodynamics is the relativistic quantum field theory of electrodynamics. In essence, it describes how light and matter interact and is the first theory where full agreement between quantum mechanics and special relativity is achieved... . The formal mathematics Formalism (mathematics) In foundations of mathematics, philosophy of mathematics, and philosophy of logic, formalism is a theory that holds that statements of mathematics and logic can be thought of as statements about the consequences of certain string manipulation rules.... of relativistic Special relativity Special relativity is the physical theory of measurement in an inertial frame of reference proposed in 1905 by Albert Einstein in the paper "On the Electrodynamics of Moving Bodies".It generalizes Galileo's... quantum mechanics Quantum mechanics Quantum mechanics, also known as quantum physics or quantum theory, is a branch of physics providing a mathematical description of much of the dual particle-like and wave-like behavior and interactions of energy and matter. It departs from classical mechanics primarily at the atomic and subatomic... also attracted his attention, although he doubted its validity. His work predicted many later finds, which include the neutron Neutron The neutron is a subatomic hadron particle which has the symbol or , no net electric charge and a mass slightly larger than that of a proton. With the exception of hydrogen, nuclei of atoms consist of protons and neutrons, which are therefore collectively referred to as nucleons. The number of... , meson Meson In particle physics, mesons are subatomic particles composed of one quark and one antiquark, bound together by the strong interaction. Because mesons are composed of sub-particles, they have a physical size, with a radius roughly one femtometer: 10−15 m, which is about the size of a proton... and neutron star Neutron star A neutron star is a type of stellar remnant that can result from the gravitational collapse of a massive star during a Type II, Type Ib or Type Ic supernova event. Such stars are composed almost entirely of neutrons, which are subatomic particles without electrical charge and with a slightly larger... . Initially, his major interest was the theory of the continuous spectrum and his first published paper, in 1926, concerned the quantum theory of molecular band spectra. He developed a method to carry out calculations of its transition probabilities. He calculated the photoelectric effect Photoelectric effect In the photoelectric effect, electrons are emitted from matter as a consequence of their absorption of energy from electromagnetic radiation of very short wavelength, such as visible or ultraviolet light. Electrons emitted in this manner may be referred to as photoelectrons... for hydrogen Hydrogen Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly... and X-rays, obtaining the absorption coefficient at the K-edge K-edge K-edge describes a sudden increase in the attenuation coefficient of photons occurring at a photon energy just above the binding energy of the K shell electron of the atoms interacting with the photons. The sudden increase in attenuation is due to photoelectric absorption of the photons... . His calculations accorded with observations of the X-ray absorption of the sun, but not hydrogen. Years later it was realized that the sun was largely composed of hydrogen and that his calculations were indeed correct. Oppenheimer also made important contributions to the theory of cosmic ray Cosmic ray Cosmic rays are energetic charged subatomic particles, originating from outer space. They may produce secondary particles that penetrate the Earth's atmosphere and surface. The term ray is historical as cosmic rays were thought to be electromagnetic radiation... showers and started work that eventually led to descriptions of quantum tunneling. In 1931 he co-wrote a paper on the "Relativistic Theory of the Photoelectric Effect" with his student Harvey Hall, in which, based on empirical evidence, he correctly disputed Dirac's assertion that two of the energy level Energy level A quantum mechanical system or particle that is bound -- that is, confined spatially—can only take on certain discrete values of energy. This contrasts with classical particles, which can have any energy. These discrete values are called energy levels... s of the hydrogen Hydrogen Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly... atom have the same energy. Subsequently, one of his doctoral students, Willis Lamb Willis Lamb Willis Eugene Lamb, Jr. was an American physicist who won the Nobel Prize in Physics in 1955 together with Polykarp Kusch "for his discoveries concerning the fine structure of the hydrogen spectrum". Lamb and Kusch were able to precisely determine certain electromagnetic properties of the electron... , determined that this was a consequence of what became known as the Lamb shift, for which Lamb was awarded the Nobel Prize in Physics in 1955. Oppenheimer worked with his first doctoral student, Melba Phillips Melba Phillips Melba Newell Phillips was an American physicist and science educator. She completed her doctoral studies under J. Robert Oppenheimer and was also known for refusing to testify before a U.S. Senate Judiciary Committee's subcommittee on internal security, her actions leading to her dismissal by... , on calculations of artificial radioactivity under bombardment by deuterons. When Ernest Lawrence Ernest Lawrence Ernest Orlando Lawrence was an American physicist and Nobel Laureate, known for his invention, utilization, and improvement of the cyclotron atom-smasher beginning in 1929, based on his studies of the works of Rolf Widerøe, and his later work in uranium-isotope separation for the Manhattan Project... and Edwin McMillan Edwin McMillan Edwin Mattison McMillan was an American physicist and Nobel laureate credited with being the first ever to produce a transuranium element. He shared the Nobel Prize in Chemistry with Glenn Seaborg in 1951.... bombarded nuclei Atomic nucleus The nucleus is the very dense region consisting of protons and neutrons at the center of an atom. It was discovered in 1911, as a result of Ernest Rutherford's interpretation of the famous 1909 Rutherford experiment performed by Hans Geiger and Ernest Marsden, under the direction of Rutherford. The... with deuterons they found the results agreed closely with the predictions of George Gamow George Gamow George Gamow , born Georgiy Antonovich Gamov , was a Russian-born theoretical physicist and cosmologist. He discovered alpha decay via quantum tunneling and worked on radioactive decay of the atomic nucleus, star formation, stellar nucleosynthesis, Big Bang nucleosynthesis, cosmic microwave... , but when higher energies and heavier nuclei were involved, the results did not conform to the theory. In 1935, Oppenheimer and Phillips worked out a theory now known as the Oppenheimer-Phillips process Oppenheimer-Phillips process The Oppenheimer–Phillips process or strip reaction is a type of deuteron-induced nuclear reaction. In this process the neutron half of an energetic deuteron fuses with a target nucleus, transmuting the target to a heavier isotope while ejecting a proton... to explain the results, a theory still in use today. As early as 1930, Oppenheimer wrote a paper essentially predicting the existence of the positron Positron The positron or antielectron is the antiparticle or the antimatter counterpart of the electron. The positron has an electric charge of +1e, a spin of ½, and has the same mass as an electron... , after a paper by Paul Dirac Paul Dirac Paul Adrien Maurice Dirac, OM, FRS was an English theoretical physicist who made fundamental contributions to the early development of both quantum mechanics and quantum electrodynamics... proposed that electrons could have both a positive charge and negative energy. Dirac's paper introduced an equation, known as the Dirac equation Dirac equation The Dirac equation is a relativistic quantum mechanical wave equation formulated by British physicist Paul Dirac in 1928. It provided a description of elementary spin-½ particles, such as electrons, consistent with both the principles of quantum mechanics and the theory of special relativity, and... , which unified quantum mechanics, special relativity Special relativity Special relativity is the physical theory of measurement in an inertial frame of reference proposed in 1905 by Albert Einstein in the paper "On the Electrodynamics of Moving Bodies".It generalizes Galileo's... and the then-new concept of electron spin Spin (physics) In quantum mechanics and particle physics, spin is a fundamental characteristic property of elementary particles, composite particles , and atomic nuclei.It is worth noting that the intrinsic property of subatomic particles called spin and discussed in this article, is related in some small ways,... , to explain the Zeeman effect Zeeman effect The Zeeman effect is the splitting of a spectral line into several components in the presence of a static magnetic field. It is analogous to the Stark effect, the splitting of a spectral line into several components in the presence of an electric field... . Oppenheimer, drawing on the body of experimental evidence, rejected the idea that the predicted positively charged electrons were proton Proton The proton is a subatomic particle with the symbol or and a positive electric charge of 1 elementary charge. One or more protons are present in the nucleus of each atom, along with neutrons. The number of protons in each atom is its atomic number.... s. He argued that they would have to have the same mass as an electron, whereas experiments showed that protons were much heavier than electrons. Two years later, Carl David Anderson Carl David Anderson Carl David Anderson was an American physicist. He is best known for his discovery of the positron in 1932, an achievement for which he received the 1936 Nobel Prize in Physics, and of the muon in 1936.-Biography:... discovered the positron, for which he received the 1936 Nobel Prize in Physics. In the late 1930s Oppenheimer became interested in astrophysics Astrophysics Astrophysics is the branch of astronomy that deals with the physics of the universe, including the physical properties of celestial objects, as well as their interactions and behavior... , probably through his friendship with Richard Tolman, resulting in a series of papers. In the first of these, a 1938 paper co-written with Robert Serber Robert Serber Robert Serber was an American physicist who participated in the Manhattan Project. He was born in Philadelphia, Pennsylvania; he was the eldest son of David Serber and Rose Frankel. He married Charlotte Leof in 1933. Rose Serber died in 1922; David married Charlotte's cousin Frances Leof in... entitled "On the Stability of Stellar Neutron Cores", Oppenheimer explored the properties of white dwarves White dwarf A white dwarf, also called a degenerate dwarf, is a small star composed mostly of electron-degenerate matter. They are very dense; a white dwarf's mass is comparable to that of the Sun and its volume is comparable to that of the Earth. Its faint luminosity comes from the emission of stored... . This was followed by a paper co-written with one of his students, George Volkoff George Volkoff George Michael Volkoff, OC, MBE, FRSC was a Canadian physicist and academic who helped, with J. Robert Oppenheimer, predict the existence of neutron stars before they were discovered.-Early life:... , "On Massive Neutron Cores", in which they demonstrated that there was a limit, the so-called Tolman-Oppenheimer-Volkoff limit Tolman-Oppenheimer-Volkoff limit The Tolman–Oppenheimer–Volkoff limit is an upper bound to the mass of stars composed of neutron-degenerate matter . The TOV limit is analogous to the Chandrasekhar limit for white dwarf stars.-History:... , to the mass Mass Mass can be defined as a quantitive measure of the resistance an object has to change in its velocity.In physics, mass commonly refers to any of the following three properties of matter, which have been shown experimentally to be equivalent:... of stars beyond which they would not remain stable as neutron stars and would undergo gravitational collapse. Finally, in 1939, Oppenheimer and another of his students, Hartland Snyder Hartland Snyder Hartland Sweet Snyder was a physicist who along with Robert Oppenheimer calculated the gravitational collapse of a pressure-free homogenous fluid sphere, and found that it could not communicate with the rest of the universe.... , produced a paper "On Continued Gravitational Attraction", which predicted the existence of what are today known as black hole Black hole A black hole is a region of spacetime from which nothing, not even light, can escape. The theory of general relativity predicts that a sufficiently compact mass will deform spacetime to form a black hole. Around a black hole there is a mathematically defined surface called an event horizon that... s. After the Born-Oppenheimer approximation paper, these papers remain his most cited, and were key factors in the rejuvenation of astrophysical research in the United States in the 1950s, mainly by John A. Wheeler. Oppenheimer's papers were considered difficult to understand even by the standards of the abstract topics he was expert in. He was 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. "His physics was good", said his student Snyder, "but his arithmetic awful." Oppenheimer published only five scientific papers, one of which was in biophysics, after World War II, and none after 1950. Murray Gell-Mann Murray Gell-Mann Murray Gell-Mann is an American physicist and linguist who received the 1969 Nobel Prize in physics for his work on the theory of elementary particles... a later Nobelist who, as a visiting scientist, worked with him at the Institute for Advanced Study Institute for Advanced Study The Institute for Advanced Study, located in Princeton, New Jersey, United States, is an independent postgraduate center for theoretical research and intellectual inquiry. It was founded in 1930 by Abraham Flexner... in 1951, offered this opinion: Oppenheimer's diverse interests sometimes interrupted his focus on projects. In 1933 he learned Sanskrit Sanskrit Sanskrit , is a historical Indo-Aryan language and the primary liturgical language of Hinduism, Jainism and Buddhism.Buddhism: besides Pali, see Buddhist Hybrid Sanskrit Today, it is listed as one of the 22 scheduled languages of India and is an official language of the state of Uttarakhand... and met the Indologist Arthur W. Ryder Arthur W. Ryder Arthur William Ryder was a professor of Sanskrit at the University of California, Berkeley. He is best known for translating a number of Sanskrit works into English, including the Panchatantra and the Bhagavad Gita. In the words of G. R. Noyes,-Life:Ryder was born on March 8, 1877 at Oberlin, Ohio... at Berkeley. He read the Bhagavad Gita Bhagavad Gita The ' , also more simply known as Gita, is a 700-verse Hindu scripture that is part of the ancient Sanskrit epic, the Mahabharata, but is frequently treated as a freestanding text, and in particular, as an Upanishad in its own right, one of the several books that constitute general Vedic tradition... in the original language and later he cited it as one of the books that most shaped his philosophy of life. His close confidant and colleague, Nobel Prize winner Isidor Rabi, later gave his own interpretation: In spite of this, observers such as Nobel Prize-winning physicist Luis Alvarez Luis Alvarez Luis W. Alvarez was an American experimental physicist and inventor, who spent nearly all of his long professional career on the faculty of the University of California, Berkeley... 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 Gravitational collapse Gravitational collapse is the inward fall of a body due to the influence of its own gravity. In any stable body, this gravitational force is counterbalanced by the internal pressure of the body, in the opposite direction to the force of gravity... , concerning neutron stars and black holes. 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. The physicist and historian Abraham Pais Abraham Pais Abraham Pais was a Dutch-born American physicist and science historian. Pais earned his Ph.D. from University of Utrecht just prior to a Nazi ban on Jewish participation in Dutch universities during World War II... once asked Oppenheimer what he considered to be his most important scientific contributions; Oppenheimer cited his work on electrons and positrons, not his work on gravitational contraction. Oppenheimer was nominated for the Nobel Prize for physics three times, in 1945, 1951 and 1967, but never won. ## Private and political life During the 1920s, Oppenheimer remained aloof from worldly matters. He claimed that he did not read newspapers or listen to the radio, and had only learned of the Wall Street crash of 1929 Wall Street Crash of 1929 The Wall Street Crash of 1929 , also known as the Great Crash, and the Stock Market Crash of 1929, was the most devastating stock market crash in the history of the United States, taking into consideration the full extent and duration of its fallout... some time after it occurred. He once remarked that he never cast a vote until the 1936 election United States presidential election, 1936 The United States presidential election of 1936 was the most lopsided presidential election in the history of the United States in terms of electoral votes. In terms of the popular vote, it was the third biggest victory since the election of 1820, which was not seriously contested.The election took... . However, from 1934 on, he became increasingly concerned about politics and international affairs. In 1934, he earmarked three percent of his salary—about$100 a year—for two years to support German physicists fleeing from Nazi Germany
Nazi Germany
Nazi Germany , also known as the Third Reich , but officially called German Reich from 1933 to 1943 and Greater German Reich from 26 June 1943 onward, is the name commonly used to refer to the state of Germany from 1933 to 1945, when it was a totalitarian dictatorship ruled by...

. During the 1934 West Coast Waterfront Strike, he and some of his students, including Melba Phillips and Bob Serber, attended a longshoremen's rally. Oppenheimer repeatedly attempted to get Serber a position at Berkeley but was blocked by Birge, who felt that "one Jew in the department was enough".

Oppenheimer's mother died in 1931, and he became closer to his father who, although still living in New York, became a frequent visitor in California. When his father died in 1937 leaving 392,602 to be divided between Oppenheimer and his brother Frank, Oppenheimer immediately wrote out a will leaving his estate to the University of California for graduate scholarships. Like many young intellectuals in the 1930s, he was a supporter of social reforms that were later alleged to be communist Communism Communism is a social, political and economic ideology that aims at the establishment of a classless, moneyless, revolutionary and stateless socialist society structured upon common ownership of the means of production... ideas. He donated to many progressive efforts which were later branded as "left-wing" during the McCarthy Joseph McCarthy Joseph Raymond "Joe" McCarthy was an American politician who served as a Republican U.S. Senator from the state of Wisconsin from 1947 until his death in 1957... era. The majority of his allegedly radical work consisted of hosting fund raisers for the Republican Second Spanish Republic The Second Spanish Republic was the government of Spain between April 14 1931, and its destruction by a military rebellion, led by General Francisco Franco.... cause in the Spanish Civil War Spanish Civil War The Spanish Civil WarAlso known as The Crusade among Nationalists, the Fourth Carlist War among Carlists, and The Rebellion or Uprising among Republicans. was a major conflict fought in Spain from 17 July 1936 to 1 April 1939... and other anti-fascist Fascism Fascism is a radical authoritarian nationalist political ideology. Fascists seek to rejuvenate their nation based on commitment to the national community as an organic entity, in which individuals are bound together in national identity by suprapersonal connections of ancestry, culture, and blood... activity. He never openly joined the Communist Party Communist Party USA The Communist Party USA is a Marxist political party in the United States, established in 1919. It has a long, complex history that is closely related to the histories of similar communist parties worldwide and the U.S. labor movement.... , though he did pass money to liberal Liberalism Liberalism is the belief in the importance of liberty and equal rights. Liberals espouse a wide array of views depending on their understanding of these principles, but generally, liberals support ideas such as constitutionalism, liberal democracy, free and fair elections, human rights,... causes by way of acquaintances who were alleged to be Party members. In 1936, Oppenheimer became involved with Jean Tatlock Jean Tatlock Jean Frances Tatlock M.D. , was an American psychiatrist, physician, and a member of the Communist Party. She is most noted for her romantic relationship with Manhattan Project scientific leader J. Robert Oppenheimer.... , the daughter of a Berkeley literature professor and a student at Stanford University School of Medicine Stanford University School of Medicine Stanford University School of Medicine is a leading medical school located at Stanford University Medical Center in Stanford, California. Originally based in San Francisco, California as Cooper Medical College, it is the oldest continuously running medical school in the western United States... . The two had similar political views; she wrote for the Western Worker, a Communist Party newspaper. Oppenheimer broke up with Tatlock in 1939. In August that year he met Katherine ("Kitty") Puening Harrison, a radical Berkeley student and former Communist Party member. Harrison had been married three times previously. Her first marriage lasted only a few months. Her second husband was Joe Dallet, an active member of the Communist party, who was killed in the Spanish Civil War. Kitty returned to the United States where she obtained a bachelor of arts Bachelor of Arts A Bachelor of Arts , from the Latin artium baccalaureus, is a bachelor's degree awarded for an undergraduate course or program in either the liberal arts, the sciences, or both... degree in botany Botany Botany, plant science, or plant biology is a branch of biology that involves the scientific study of plant life. Traditionally, botany also included the study of fungi, algae and viruses... from the University of Pennsylvania University of Pennsylvania The University of Pennsylvania is a private, Ivy League university located in Philadelphia, Pennsylvania, United States. Penn is the fourth-oldest institution of higher education in the United States,Penn is the fourth-oldest using the founding dates claimed by each institution... . There she married Richard Harrison, a physician and medical researcher, in 1938. In June 1939 Kitty and Harrison moved to Pasadena, California Pasadena, California Pasadena is a city in Los Angeles County, California, United States. Although famous for hosting the annual Rose Bowl football game and Tournament of Roses Parade, Pasadena is the home to many scientific and cultural institutions, including the California Institute of Technology , the Jet... , where he became chief of radiology at a local hospital and she enrolled as a graduate student at the University of California, Los Angeles University of California, Los Angeles The University of California, Los Angeles is a public research university located in the Westwood neighborhood of Los Angeles, California, USA. It was founded in 1919 as the "Southern Branch" of the University of California and is the second oldest of the ten campuses... . Oppenheimer and Kitty created a minor scandal by sleeping together after one of Tolman's parties. In the summer of 1940 she stayed with Oppenheimer at his ranch in New Mexico. She finally asked Harrison for a divorce when she found out she was pregnant. When he refused, she obtained an instant divorce in Reno, Nevada Reno, Nevada Reno is the county seat of Washoe County, Nevada, United States. The city has a population of about 220,500 and is the most populous Nevada city outside of the Las Vegas metropolitan area... , and married Oppenheimer on November 1, 1940. Their first child Peter was born in May 1941, and their second child, Katherine ("Toni"), was born in Los Alamos, New Mexico Los Alamos, New Mexico Los Alamos is a townsite and census-designated place in Los Alamos County, New Mexico, United States, built upon four mesas of the Pajarito Plateau and the adjoining White Rock Canyon. The population of the CDP was 12,019 at the 2010 Census. The townsite or "the hill" is one part of town while... , on December 7, 1944. During his marriage, Oppenheimer continued his affair with Jean Tatlock. Later their continued contact became an issue in his security clearance hearings because of Tatlock's Communist associations. Many of Oppenheimer's closest associates were active in the Communist Party in the '30s or '40s. They included his brother Frank, Frank's wife Jackie, Kitty, Jean Tatlock, his landlady Mary Ellen Washburn, and several of his graduate students at Berkeley. When he joined the Manhattan Project in 1942, Oppenheimer wrote on his personal security questionnaire that he [Oppenheimer] had been "a member of just about every Communist Front organization on the West Coast". Years later he claimed that he did not remember saying this, that it was not true, and that if he had said anything along those lines, it was "a half-jocular overstatement". He was a subscriber to the People's World, a Communist Party organ, and he testified in 1954, "I was associated with the Communist movement." From 1937 to 1942, in the midst of the Great Purge Great Purge The Great Purge was a series of campaigns of political repression and persecution in the Soviet Union orchestrated by Joseph Stalin from 1936 to 1938... 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 Haakon Chevalier Haakon Maurice Chevalier was an author, translator, and professor of French literature at the University of California, Berkeley best known for his friendship with physicist J... and Gordon Griffiths, as a "closed" (secret) unit of the Communist Party for Berkeley faculty. The Federal Bureau of Investigation Federal Bureau of Investigation The Federal Bureau of Investigation is an agency of the United States Department of Justice that serves as both a federal criminal investigative body and an internal intelligence agency . The FBI has investigative jurisdiction over violations of more than 200 categories of federal crime... (FBI) recorded that J. Robert Oppenheimer attended a meeting in the home of self-proclaimed Communist Haakon Chevalier, that the Communist Party's California state chairman William Schneiderman, and Isaac Folkoff Isaac Folkoff Isaac "Pop" Folkoff was a senior founding member of the California Communist Party and West Coast liaison between Soviet intelligence and the Communist Party USA . Folkoff was in charge of West Coast operations. Folkoff worked as a courier passing information to and from Soviet sources, and as a... , West Coast liaison between the Communist Party and NKVD NKVD The People's Commissariat for Internal Affairs was the public and secret police organization of the Soviet Union that directly executed the rule of power of the Soviets, including political repression, during the era of Joseph Stalin.... , attended in Fall 1940, during the Hitler-Stalin pact. Shortly thereafter, the FBI added Oppenheimer to its Custodial Detention Index, for arrest in case of national emergency, and listed him as "Nationalistic Tendency: Communist". Debates over Oppenheimer's Party membership or lack thereof have turned on very fine points; almost all historians agree he had strong socialist sympathies during this time and interacted with Party members, though there is considerable dispute over whether he was officially a member of the Party. At his 1954 security clearance hearings, he denied being a member of the Communist Party, but identified himself as a fellow traveler, which he defined as someone who agrees with many of the goals of Communism, but without being willing to blindly follow orders from any Communist party apparatus. Throughout the development of the atomic bomb, Oppenheimer was under investigation by both the FBI and the Manhattan Project's internal security arm for his past left-wing associations. He was followed by Army security agents during a trip to California California California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area... in June 1943 to visit his former girlfriend, Jean Tatlock, who was suffering from depression. Oppenheimer spent the night in her apartment. Jean committed suicide on January 4, 1944, which left Oppenheimer deeply grieved. In August 1943, he volunteered to Manhattan Project security agents that George Eltenton, whom he did not know, had solicited three men at Los Alamos for nuclear secrets on behalf of the Soviet Union. When pressed on the issue in later interviews, Oppenheimer admitted that the only person who had approached him was his friend Haakon Chevalier, a Berkeley professor of French literature, who had mentioned the matter privately at a dinner at Oppenheimer's house. Brigadier General Brigadier general (United States) A brigadier general in the United States Army, Air Force, and Marine Corps, is a one-star general officer, with the pay grade of O-7. Brigadier general ranks above a colonel and below major general. Brigadier general is equivalent to the rank of rear admiral in the other uniformed... Leslie R. Groves, Jr., the director of the Manhattan Project, thought Oppenheimer was too important to the project to be ousted over this suspicious behavior. On July 20, 1943, he wrote to the Manhattan Engineer District: ### Los Alamos On October 9, 1941, shortly before the United States entered World War II World War II World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis... , President President of the United States The President of the United States of America is the head of state and head of government of the United States. The president leads the executive branch of the federal government and is the commander-in-chief of the United States Armed Forces.... Franklin D. Roosevelt Franklin D. Roosevelt Franklin Delano Roosevelt , also known by his initials, FDR, was the 32nd President of the United States and a central figure in world events during the mid-20th century, leading the United States during a time of worldwide economic crisis and world war... approved a crash program to develop an atomic bomb. In May 1942, National Defense Research Committee National Defense Research Committee The National Defense Research Committee was an organization created "to coordinate, supervise, and conduct scientific research on the problems underlying the development, production, and use of mechanisms and devices of warfare" in the United States from June 27, 1940 until June 28, 1941... Chairman James B. Conant, who had been one of Oppenheimer's lecturers at Harvard, invited Oppenheimer to take over work on fast neutron calculations, a task that Oppenheimer threw himself into with full vigor. He was given the title "Coordinator of Rapid Rupture", specifically referring to the propagation of a fast neutron chain reaction in an atomic bomb. One of his 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 Emil Konopinski Emil John Konopinski was an American nuclear scientist of Polish origin. His parents were Joseph and Sophia Sniegowska.... , Felix Bloch Felix Bloch Felix Bloch was a Swiss physicist, working mainly in the U.S.-Life and work:Bloch was born in Zürich, Switzerland to Jewish parents Gustav and Agnes Bloch. He was educated there and at the Eidgenössische Technische Hochschule, also in Zürich. Initially studying engineering he soon changed to physics... , Hans Bethe Hans Bethe Hans Albrecht Bethe was a German-American nuclear physicist, and Nobel laureate in physics for his work on the theory of stellar nucleosynthesis. A versatile theoretical physicist, Bethe also made important contributions to quantum electrodynamics, nuclear physics, solid-state physics and... and Edward Teller Edward Teller Edward Teller was a Hungarian-American theoretical physicist, known colloquially as "the father of the hydrogen bomb," even though he did not care for the title. Teller made numerous contributions to nuclear and molecular physics, spectroscopy , and surface physics... —busied themselves calculating what needed to be done, and in what order, to make the bomb. In June 1942, the US Army established the Manhattan Engineer District to handle its part in the atom bomb project, beginning the process of transferring responsibility from the Office of Scientific Research and Development Office of Scientific Research and Development The Office of Scientific Research and Development was an agency of the United States federal government created to coordinate scientific research for military purposes during World War II. Arrangements were made for its creation during May 1941, and it was created formally by on June 28, 1941... to the military. In September, Brigadier General Leslie R. Groves, Jr., was appointed director of what became known as the Manhattan Project. Groves selected Oppenheimer to head the project's secret weapons laboratory, a choice which surprised many, as Oppenheimer was not known to be politically aligned with the conservative military, nor to be an efficient leader of large projects. The fact that he did not have a Nobel Prize, and might not have the prestige to direct fellow scientists, did concern Groves. However, he was impressed by Oppenheimer's singular grasp of the practical aspects of designing and constructing an atomic bomb, and by the breadth of his knowledge. As a military engineer Military engineer In military science, engineering refers to the practice of designing, building, maintaining and dismantling military works, including offensive, defensive and logistical structures, to shape the physical operating environment in war... , Groves knew that this would be vital in an interdisciplinary project that would involve not just physics, but chemistry, metallurgy Metallurgy Metallurgy is a domain of materials science that studies the physical and chemical behavior of metallic elements, their intermetallic compounds, and their mixtures, which are called alloys. It is also the technology of metals: the way in which science is applied to their practical use... , ordnance and engineering Engineering Engineering is the discipline, art, skill and profession of acquiring and applying scientific, mathematical, economic, social, and practical knowledge, in order to design and build structures, machines, devices, systems, materials and processes that safely realize improvements to the lives of... . Groves also detected in Oppenheimer something that many others did not, an "overweening ambition" that Groves reckoned would supply the drive necessary to push the project to a successful conclusion. Isidor Rabi considered the appointment "a real stroke of genius on the part of General Groves, who was not generally considered to be a genius". Oppenheimer and Groves decided that for security and cohesion they needed a centralized, secret research laboratory in a remote location. Scouting for a site in late 1942, Oppenheimer was drawn to New Mexico, not far from his ranch. On November 16, 1942, Oppenheimer, Groves and others toured a prospective site. Oppenheimer feared that the high cliffs surrounding the site would make his people feel claustrophobic, while the engineers were concerned with the possibility of flooding. He then suggested and championed a site that he knew well: a flat mesa Mesa A mesa or table mountain is an elevated area of land with a flat top and sides that are usually steep cliffs. It takes its name from its characteristic table-top shape.... near Santa Fe, New Mexico Santa Fe, New Mexico Santa Fe is the capital of the U.S. state of New Mexico. It is the fourth-largest city in the state and is the seat of . Santa Fe had a population of 67,947 in the 2010 census... , which was the site of a private boys' school called the Los Alamos Ranch School Los Alamos Ranch School Los Alamos Ranch School was a private boarding school for boys in Los Alamos County, New Mexico, near Otowi, in what would eventually become Los Alamos, New Mexico... . The engineers were concerned about the poor access road and the water supply, but otherwise felt that it was ideal. The Los Alamos laboratory Los Alamos National Laboratory Los Alamos National Laboratory is a United States Department of Energy national laboratory, managed and operated by Los Alamos National Security , located in Los Alamos, New Mexico... was built on the site of the school, taking over some of its buildings, while many others were erected in great haste. There Oppenheimer assembled a group of the top physicists of the time, which he referred to as the "luminaries". Initially Los Alamos was supposed to be a military laboratory, and Oppenheimer and other researchers were to be commissioned into the Army. He went so far as to order himself a lieutenant colonel's uniform and take the Army physical test, which he failed. Army doctors considered him underweight at 128 pounds (58.1 kg), diagnosed his chronic cough as tuberculosis Tuberculosis Tuberculosis, MTB, or TB is a common, and in many cases lethal, infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis. Tuberculosis usually attacks the lungs but can also affect other parts of the body... and were concerned about his chronic lumbosacral joint Lumbosacral joint The lumbosacral joint is a joint of the body, between the last lumbar vertebra and the first sacral segment of the spinal cord.... pain. The plan to commission scientists fell through when Robert Bacher Robert Bacher Robert Fox Bacher was an American nuclear physicist and one of the leaders of the Manhattan Project.-Early life and career:... and Isidor Rabi balked at the idea. Conant, Groves, and Oppenheimer devised a compromise whereby the laboratory was operated by the University of California under contract to the War Department United States Department of War The United States Department of War, also called the War Department , was the United States Cabinet department originally responsible for the operation and maintenance of the United States Army... . It soon turned out that Oppenheimer had hugely underestimated the magnitude of the project; Los Alamos grew from a few hundred people in 1943 to over 6,000 in 1945. Oppenheimer at first had difficulty with the organizational division of large groups, but rapidly learned the art of large-scale administration after he took up permanent residence on the mesa. He 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 symbol of what they were working toward as a scientific director. Victor Weisskopf put it thus: In 1943 development efforts were directed to a plutonium Plutonium Plutonium is a transuranic radioactive chemical element with the chemical symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, forming a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation... gun-type fission weapon Gun-type fission weapon Gun-type fission weapons are fission-based nuclear weapons whose design assembles their fissile material into a supercritical mass by the use of the "gun" method: shooting one piece of sub-critical material into another... called "Thin Man". Initial research on the properties of plutonium was done using cyclotron Cyclotron In technology, a cyclotron is a type of particle accelerator. In physics, the cyclotron frequency or gyrofrequency is the frequency of a charged particle moving perpendicularly to the direction of a uniform magnetic field, i.e. a magnetic field of constant magnitude and direction... -generated plutonium-239 Plutonium-239 Plutonium-239 is an isotope of plutonium. Plutonium-239 is the primary fissile isotope used for the production of nuclear weapons, although uranium-235 has also been used and is currently the secondary isotope. Plutonium-239 is also one of the three main isotopes demonstrated usable as fuel in... , which was extremely pure but could only be created in tiny amounts. When Los Alamos received the first sample of plutonium from the X-10 Graphite Reactor X-10 Graphite Reactor The X-10 Graphite Reactor at Oak Ridge National Laboratory in Oak Ridge, Tennessee, formerly known as the Clinton Pile and X-10 Pile, was the world's second artificial nuclear reactor and was the first reactor designed and built for continuous operation.When President Roosevelt in December 1942... in April 1944 a problem was discovered: reactor-bred plutonium had a higher concentration of plutonium-240 Plutonium-240 Plutonium-240 is an isotope of the metal plutonium formed when plutonium-239 captures a neutron. About 62% to 73% of the time when Pu-239 captures a neutron it undergoes fission; the rest of the time it forms Pu-240. The longer a nuclear fuel element remains in a nuclear reactor the greater the... , making it unsuitable for use in a gun-type weapon. In July 1944, Oppenheimer abandoned the gun design in favor of an implosion-type Nuclear weapon design Nuclear weapon designs are physical, chemical, and engineering arrangements that cause the physics package of a nuclear weapon to detonate. There are three basic design types... weapon. Using chemical explosive lens Explosive lens An explosive lens—as used, for example, in nuclear weapons—is a highly specialized explosive charge, a special type of a shaped charge. In general, it is a device composed of several explosive charges that are shaped in such a way as to change the shape of the detonation wave passing through it,... es, a sub-critical sphere of fissile material could be squeezed into a smaller and denser form. The metal needed to travel only very short distances, so the critical mass would be assembled in much less time. In August 1944 Oppenheimer implemented a sweeping reorganization of the Los Alamos laboratory to focus on implosion. He concentrated the development efforts on the gun-type device, a simpler design that only had to work with uranium-235 Uranium-235 - References :* .* DOE Fundamentals handbook: Nuclear Physics and Reactor theory , .* A piece of U-235 the size of a grain of rice can produce energy equal to that contained in three tons of coal or fourteen barrels of oil. -External links:* * * one of the earliest articles on U-235 for the... , in a single group, and this device became Little Boy Little Boy "Little Boy" was the codename of the atomic bomb dropped on Hiroshima on August 6, 1945 by the Boeing B-29 Superfortress Enola Gay, piloted by Colonel Paul Tibbets of the 393rd Bombardment Squadron, Heavy, of the United States Army Air Forces. It was the first atomic bomb to be used as a weapon... in February 1945. After a mammoth research effort, the more complex design of the implosion device, known as the "Christy gadget" after Robert Christy Robert Christy Robert F. Christy is an American theoretical physicist and later astrophysicist who worked on the Manhattan Project. He was also briefly president of Caltech.... , another student of Oppenheimer's, was finalized in a meeting in Oppenheimer's office on February 28, 1945. In May 1945 an Interim Committee Interim Committee The Interim Committee was a secret high-level group created in May 1945 by United States Secretary of War Henry L. Stimson at the urging of leaders of the Manhattan Project and with the approval of President Harry S. Truman to advise on matters pertaining to nuclear energy... was created to advise and report on wartime and postwar policies regarding the use of nuclear energy. The Interim Committee in turn established a scientific panel consisting of Compton Arthur Compton Arthur Holly Compton was an American physicist and Nobel laureate in physics for his discovery of the Compton effect. He served as Chancellor of Washington University in St. Louis from 1945 to 1953.-Early years:... , Fermi, Lawrence and Oppenheimer to advise it on scientific issues. In its presentation to the Interim Committee the scientific panel offered its opinion not just on the likely physical effects of an atomic bomb, but on its likely military and political impact. This included opinions on such sensitive issues as whether or not the Soviet Union should be advised of the weapon in advance of its use against Japan. ### Trinity The joint work of the scientists at Los Alamos resulted in the first artificial nuclear explosion Nuclear explosion A nuclear explosion occurs as a result of the rapid release of energy from an intentionally high-speed nuclear reaction. The driving reaction may be nuclear fission, nuclear fusion or a multistage cascading combination of the two, though to date all fusion based weapons have used a fission device... near Alamogordo on July 16, 1945, on a site that Oppenheimer codenamed "Trinity" in mid-1944. He later said this name was from one of John Donne John Donne John Donne 31 March 1631), English poet, satirist, lawyer, and priest, is now considered the preeminent representative of the metaphysical poets. His works are notable for their strong and sensual style and include sonnets, love poetry, religious poems, Latin translations, epigrams, elegies, songs,... 's Holy Sonnets Holy Sonnets The Holy Sonnets, also known as the Divine Meditations or Divine Sonnets, are a series of nineteen poems by the English poet John Donne... . 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. Oppenheimer later recalled that, while witnessing the explosion, he thought of a verse from the Hindu Hindu Hindu refers to an identity associated with the philosophical, religious and cultural systems that are indigenous to the Indian subcontinent. As used in the Constitution of India, the word "Hindu" is also attributed to all persons professing any Indian religion... holy book, the Bhagavad Gita Bhagavad Gita The ' , also more simply known as Gita, is a 700-verse Hindu scripture that is part of the ancient Sanskrit epic, the Mahabharata, but is frequently treated as a freestanding text, and in particular, as an Upanishad in its own right, one of the several books that constitute general Vedic tradition... : Years later he would explain that another verse had also entered his head at that time: namely, the famous verse: "", which he translated as "I am become Death, the destroyer of worlds." In 1965, he was persuaded to quote again for a television broadcast: According to his brother, at the time Oppenheimer simply exclaimed, "It worked." A contemporary account by Brigadier General Thomas Farrell, who was present in the control bunker at the site with Oppenheimer, summarized his reaction as follows: For his services as director of Los Alamos, Oppenheimer was awarded the Medal for Merit from the U.S. President in 1946. ## Postwar activities After the atomic bombings of Hiroshima and Nagasaki Atomic bombings of Hiroshima and Nagasaki During the final stages of World War II in 1945, the United States conducted two atomic bombings against the cities of Hiroshima and Nagasaki in Japan, the first on August 6, 1945, and the second on August 9, 1945. These two events are the only use of nuclear weapons in war to date.For six months... , the Manhattan Project became public knowledge; and Oppenheimer became a national spokesman for science, emblematic of a new type of technocratic power. He became a household name and his face appeared on the covers of Life Life (magazine) Life generally refers to three American magazines:*A humor and general interest magazine published from 1883 to 1936. Time founder Henry Luce bought the magazine in 1936 solely so that he could acquire the rights to its name.... and Time Time (magazine) Time is an American news magazine. A European edition is published from London. Time Europe covers the Middle East, Africa and, since 2003, Latin America. An Asian edition is based in Hong Kong... . 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. Like many scientists of his generation, he felt that security from atomic bombs would come only from a transnational organization such as the newly formed United Nations United Nations The United Nations is an international organization whose stated aims are facilitating cooperation in international law, international security, economic development, social progress, human rights, and achievement of world peace... , which could institute a program to stifle a nuclear arms race Nuclear arms race The nuclear arms race was a competition for supremacy in nuclear warfare between the United States, the Soviet Union, and their respective allies during the Cold War... . ### Institute for Advanced Study In November 1945, Oppenheimer left Los Alamos to return to Caltech, but he soon found that his heart was no longer in teaching. In 1947, he accepted an offer from Lewis Strauss to take up the directorship of the Institute for Advanced Study Institute for Advanced Study The Institute for Advanced Study, located in Princeton, New Jersey, United States, is an independent postgraduate center for theoretical research and intellectual inquiry. It was founded in 1930 by Abraham Flexner... in Princeton, New Jersey Princeton, New Jersey Princeton is a community located in Mercer County, New Jersey, United States. It is best known as the location of Princeton University, which has been sited in the community since 1756... . This meant moving back east and leaving Ruth Tolman, the wife of his friend Richard Tolman, with whom he had begun an affair after leaving Los Alamos. The job came with a salary of20,000 per annum, plus rent-free accommodation in the director's house, a 17th century manor with a cook and groundskeeper, surrounded by 265 acres (107.2 ha) of woodlands.

Oppenheimer brought together intellectuals at the height of their powers and from a variety of disciplines to solve the most pertinent questions of the age. He directed and encouraged the research of many well-known scientists, including Freeman Dyson
Freeman Dyson
Freeman John Dyson FRS is a British-born American theoretical physicist and mathematician, famous for his work in quantum field theory, solid-state physics, astronomy and nuclear engineering. Dyson is a member of the Board of Sponsors of the Bulletin of the Atomic Scientists...

, and the duo of Chen Ning Yang and Tsung-Dao Lee
Tsung-Dao Lee
Tsung-Dao Lee is a Chinese born-American physicist, well known for his work on parity violation, the Lee Model, particle physics, relativistic heavy ion physics, nontopological solitons and soliton stars....

, who won a Nobel Prize for their discovery of parity
Parity (physics)
In physics, a parity transformation is the flip in the sign of one spatial coordinate. In three dimensions, it is also commonly described by the simultaneous flip in the sign of all three spatial coordinates:...

non-conservation. He also instituted temporary memberships for scholars from the humanities, such as T. S. Eliot
T. S. Eliot
Thomas Stearns "T. S." Eliot OM was a playwright, literary critic, and arguably the most important English-language poet of the 20th century. Although he was born an American he moved to the United Kingdom in 1914 and was naturalised as a British subject in 1927 at age 39.The poem that made his...

and George F. Kennan
George F. Kennan
George Frost Kennan was an American adviser, diplomat, political scientist and historian, best known as "the father of containment" and as a key figure in the emergence of the Cold War...

. Some of these activities were resented by a few members of the mathematics faculty, who wanted the institute to stay a bastion of pure scientific research. Abraham Pais said that Oppenheimer himself thought that one of his failures at the institute was being unable to bring together scholars from the natural sciences and the humanities.

A series of conferences in New York from 1947 through 1949 saw physicists switch back from war work to theoretical issues. Under Oppenheimer's direction, physicists tackled the greatest outstanding problem of the pre-war years: infinite, divergent, and non-sensical expressions in the quantum electrodynamics
Quantum electrodynamics
Quantum electrodynamics is the relativistic quantum field theory of electrodynamics. In essence, it describes how light and matter interact and is the first theory where full agreement between quantum mechanics and special relativity is achieved...

of elementary particle
Elementary particle
In particle physics, an elementary particle or fundamental particle is a particle not known to have substructure; that is, it is not known to be made up of smaller particles. If an elementary particle truly has no substructure, then it is one of the basic building blocks of the universe from which...

s. Julian Schwinger
Julian Schwinger
Julian Seymour Schwinger was an American theoretical physicist. He is best known for his work on the theory of quantum electrodynamics, in particular for developing a relativistically invariant perturbation theory, and for renormalizing QED to one loop order.Schwinger is recognized as one of the...

, Richard Feynman
Richard Feynman
Richard Phillips Feynman was an American physicist known for his work in the path integral formulation of quantum mechanics, the theory of quantum electrodynamics and the physics of the superfluidity of supercooled liquid helium, as well as in particle physics...

and Shin'ichiro Tomonaga tackled the problem of regularization
Regularization (physics)
-Introduction:In physics, especially quantum field theory, regularization is a method of dealing with infinite, divergent, and non-sensical expressions by introducing an auxiliary concept of a regulator...

, and developed techniques which became known as renormalization
Renormalization
In quantum field theory, the statistical mechanics of fields, and the theory of self-similar geometric structures, renormalization is any of a collection of techniques used to treat infinities arising in calculated quantities....

. Freeman Dyson was able to prove that their procedures gave similar results. The problem of meson absorption and Hideki Yukawa
Hideki Yukawa
né , was a Japanese theoretical physicist and the first Japanese Nobel laureate.-Biography:Yukawa was born in Tokyo and grew up in Kyoto. In 1929, after receiving his degree from Kyoto Imperial University, he stayed on as a lecturer for four years. After graduation, he was interested in...

's theory of meson
Meson
In particle physics, mesons are subatomic particles composed of one quark and one antiquark, bound together by the strong interaction. Because mesons are composed of sub-particles, they have a physical size, with a radius roughly one femtometer: 10−15 m, which is about the size of a proton...

s as the carrier particles of the strong nuclear force were also tackled. Probing questions from Oppenheimer prompted Robert Marshak
Robert Marshak
Robert Eugene Marshak was an American physicist dedicated to learning, research, and education.-History:...

's innovative two-meson
Meson
In particle physics, mesons are subatomic particles composed of one quark and one antiquark, bound together by the strong interaction. Because mesons are composed of sub-particles, they have a physical size, with a radius roughly one femtometer: 10−15 m, which is about the size of a proton...

hypothesis
Hypothesis
A hypothesis is a proposed explanation for a phenomenon. The term derives from the Greek, ὑποτιθέναι – hypotithenai meaning "to put under" or "to suppose". For a hypothesis to be put forward as a scientific hypothesis, the scientific method requires that one can test it...

: that there were actually two types of mesons, pion
Pion
In particle physics, a pion is any of three subatomic particles: , , and . Pions are the lightest mesons and they play an important role in explaining the low-energy properties of the strong nuclear force....

s and muon
Muon
The muon |mu]] used to represent it) is an elementary particle similar to the electron, with a unitary negative electric charge and a spin of ½. Together with the electron, the tau, and the three neutrinos, it is classified as a lepton...

s. This led to Cecil Frank Powell
Cecil Frank Powell
Cecil Frank Powell, FRS was a British physicist, and Nobel Prize in Physics laureate for his development of the photographic method of studying nuclear processes and for the resulting discovery of the pion , a heavy subatomic particle.Powell was born in Tonbridge, Kent, England, the son of a local...

's breakthrough and subsequent Nobel Prize for the discovery of the pion.

### Atomic Energy Commission

As a member of the Board of Consultants to a committee appointed by President Harry S. Truman
Harry S. Truman
Harry S. Truman was the 33rd President of the United States . As President Franklin D. Roosevelt's third vice president and the 34th Vice President of the United States , he succeeded to the presidency on April 12, 1945, when President Roosevelt died less than three months after beginning his...

, Oppenheimer strongly influenced the Acheson–Lilienthal Report. In this report, the committee advocated creation of an international Atomic Development Authority, which would own all fissionable material and the means of its production, such as mines and laboratories, and atomic power plants where it could be used for peaceful energy production. Bernard Baruch
Bernard Baruch
Bernard Mannes Baruch was an American financier, stock-market speculator, statesman, and political consultant. After his success in business, he devoted his time toward advising U.S. Presidents Woodrow Wilson and Franklin D. Roosevelt on economic matters and became a philanthropist.-Early life...

was appointed to translate this report into a proposal to the United Nations, resulting in the Baruch Plan
Baruch Plan
The Baruch Plan was a proposal by the United States government, written largely by Bernard Baruch but based on the Acheson–Lilienthal Report, to the United Nations Atomic Energy Commission in its first meeting in June 1946...

of 1946. The Baruch Plan introduced many additional provisions regarding enforcement, in particular requiring inspection of the Soviet Union's uranium resources. The Baruch Plan was seen as an attempt to maintain the United States' nuclear monopoly and was rejected by the Soviets. With this, it became clear to Oppenheimer that an arms race was unavoidable, due to the mutual suspicion of the United States and the Soviet Union, which even Oppenheimer was starting to distrust.
After the Atomic Energy Commission (AEC) came into being in 1947 as a civilian agency in control of nuclear research and weapons issues, Oppenheimer was appointed as the Chairman of its General Advisory Committee (GAC). From this position he advised on a number of nuclear-related issues, including project funding, laboratory construction and even international policy—though the GAC's advice was not always heeded. As Chairman of the GAC, Oppenheimer lobbied vigorously for international arms control and funding for basic science, and attempted to influence policy away from a heated arms race. When the government questioned whether to pursue a crash program to develop an atomic weapon based on nuclear fusion
Nuclear fusion
Nuclear fusion is the process by which two or more atomic nuclei join together, or "fuse", to form a single heavier nucleus. This is usually accompanied by the release or absorption of large quantities of energy...

—the hydrogen bomb—Oppenheimer initially recommended against it, though he had been in favor of developing such a weapon during the Manhattan Project. He was motivated partly by ethical concerns, feeling that such a weapon could only be used strategically against civilian targets, resulting in millions of deaths. He was also motivated by practical concerns, however, as at the time there was no workable design for a hydrogen bomb. Oppenheimer felt that resources would be better spent creating a large force of fission weapons. He and others were especially concerned about nuclear reactors being diverted from plutonium to tritium
Tritium
Tritium is a radioactive isotope of hydrogen. The nucleus of tritium contains one proton and two neutrons, whereas the nucleus of protium contains one proton and no neutrons...

production. They were overridden by Truman, who announced a crash program after the Soviet Union tested their first atomic bomb in 1949. Oppenheimer and other GAC opponents of the project, especially James Conant
James Bryant Conant
James Bryant Conant was a chemist, educational administrator, and government official. As thePresident of Harvard University he reformed it as a research institution.-Biography :...

, felt personally shunned and considered retiring from the committee. They stayed on, though their views on the hydrogen bomb were well known.

In 1951, however, Edward Teller
Edward Teller
Edward Teller was a Hungarian-American theoretical physicist, known colloquially as "the father of the hydrogen bomb," even though he did not care for the title. Teller made numerous contributions to nuclear and molecular physics, spectroscopy , and surface physics...

and mathematician Stanislaw Ulam developed what became known as the Teller-Ulam design
Teller-Ulam design
The Teller–Ulam design is the nuclear weapon design concept used in most of the world's nuclear weapons. It is colloquially referred to as "the secret of the hydrogen bomb" because it employs hydrogen fusion, though in most applications the bulk of its destructive energy comes from uranium fission,...

for a hydrogen bomb. This new design seemed technically feasible and Oppenheimer changed his opinion about developing the weapon. As he later recalled:

### Security hearing

The FBI under J. Edgar Hoover
J. Edgar Hoover
John Edgar Hoover was the first Director of the Federal Bureau of Investigation of the United States. Appointed director of the Bureau of Investigation—predecessor to the FBI—in 1924, he was instrumental in founding the FBI in 1935, where he remained director until his death in 1972...

had been following Oppenheimer since before the war, when he showed Communist sympathies as a professor at Berkeley and had been close to members of the Communist Party, including his wife and brother. He had been under close surveillance since the early 1940s, his home and office bugged, his phone tapped and his mail opened. The FBI furnished Oppenheimer's political enemies with incriminating evidence about his Communist ties. These enemies included Lewis Strauss, an AEC commissioner who had long harbored resentment against Oppenheimer both for his activity in opposing the hydrogen bomb and for his humiliation of Strauss before Congress some years earlier; regarding Strauss's opposition to the export of radioactive isotopes to other nations, Oppenheimer had memorably categorized these as "less important than electronic devices but more important than, let us say, vitamins."

On June 7, 1949, Oppenheimer testified before the House Un-American Activities Committee
House Un-American Activities Committee
The House Committee on Un-American Activities or House Un-American Activities Committee was an investigative committee of the United States House of Representatives. In 1969, the House changed the committee's name to "House Committee on Internal Security"...

, where he admitted that he had associations with the Communist Party in the 1930s. He testified that some of his students, including David Bohm
David Bohm
David Joseph Bohm FRS was an American-born British quantum physicist who contributed to theoretical physics, philosophy, neuropsychology, and the Manhattan Project.-Youth and college:...

, Giovanni Rossi Lomanitz
Giovanni Rossi Lomanitz
Ross Lomanitz was an American physicist.He was born in Bryan, Texas and grew up in Oklahoma. His father was an agricultural chemist and named his son after the Italian socialist Giovanni Rossi, who had founded an agricultural commune in Brazil in the 1890s...

, Philip Morrison
Philip Morrison
Philip Morrison, was Institute Professor Emeritus and Professor of Physics Emeritus at the Massachusetts Institute of Technology .-Early life and education:...

, Bernard Peters and Joseph Weinberg, had been Communists at the time they had worked with him at Berkeley. Frank Oppenheimer and his wife Jackie testified before the HUAC and admitted that they had been members of the Communist Party. Frank was subsequently fired from his University of Michigan
University of Michigan
The University of Michigan is a public research university located in Ann Arbor, Michigan in the United States. It is the state's oldest university and the flagship campus of the University of Michigan...

position. Unable to find work in physics for many years, he became instead a cattle rancher in Colorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...

. He later taught high school physics and was the founder of the San Francisco Exploratorium
Exploratorium
The Exploratorium is a museum in San Francisco with over 475 participatory exhibits, all of them made onsite, that mix science and art. It also aims to promote museums as informal education centers....

.

Oppenheimer had found himself in the middle of more than one controversy and power struggle in the years from 1949 to 1953. Edward Teller, who had been so uninterested in work on the atomic bomb at Los Alamos during the war that Oppenheimer had given him time instead to work on his own project of the hydrogen bomb, had eventually left Los Alamos to help found, in 1951, a second laboratory at what would become the Lawrence Livermore National Laboratory
Lawrence Livermore National Laboratory
The Lawrence Livermore National Laboratory , just outside Livermore, California, is a Federally Funded Research and Development Center founded by the University of California in 1952...

. There, he could be free of Los Alamos control to develop the hydrogen bomb. Long-range thermonuclear "strategic" weapons delivered by jet bombers would necessarily be under control of the new United States Air Force
United States Air Force
The United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...

(USAF). Oppenheimer had for some years pushed for smaller "tactical" nuclear weapons which would be more useful in a limited theater against enemy troops and which would be under control of the Army. The two services fought for control of nuclear weapons, often allied with different political parties. The USAF, with Teller pushing its program, gained ascendance in the Republican
Republican Party (United States)
The Republican Party is one of the two major contemporary political parties in the United States, along with the Democratic Party. Founded by anti-slavery expansion activists in 1854, it is often called the GOP . The party's platform generally reflects American conservatism in the U.S...

-controlled administration following the election of Dwight D. Eisenhower
Dwight D. Eisenhower
Dwight David "Ike" Eisenhower was the 34th President of the United States, from 1953 until 1961. He was a five-star general in the United States Army...

as president in 1952.

In 1950, Paul Crouch, Communist Party organizer for Alameda County from April 1941 to early January 1942, was the first person to accuse Oppenheimer of Communist Party ties. He testified before a Congressional committee that Oppenheimer had hosted a Communist Party meeting at his Berkeley home. The charges were widely publicized at the time. However, Oppenheimer was able to prove that he was in New Mexico at the time and Crouch over time was shown to be an unreliable informant. In November 1953, J. Edgar Hoover was sent a letter concerning Oppenheimer by William Liscum Borden, former executive director of Congress' Joint Atomic Energy Committee. In the letter, Borden stated his opinion "based upon years of study, of the available classified evidence, that more probably than not J. Robert Oppenheimer is an agent of the Soviet Union."
Strauss and Senator Brien McMahon
Brien McMahon
Brien McMahon, born James O'Brien McMahon was an American lawyer and politician who served in the United States Senate from 1945 to 1952...

Teller testified against Oppenheimer, saying that he considered him loyal, but of such questionable judgment that he should be relieved of clearance on the basis of bad decision-making. This led to outrage by the scientific community and Teller's virtual expulsion from academic science. Groves, threatened by the FBI as having been potentially part of a coverup about the Chevalier contact in 1943, likewise testified against Oppenheimer. Many top scientists, as well as government and military figures, testified on Oppenheimer's behalf. Inconsistencies in his testimony and his erratic behavior on the stand, at one point saying he had given a "cock and bull story" and that this was because he "was an idiot", convinced some that he was unstable, unreliable and a possible security risk. Oppenheimer's clearance was revoked one day before it was slated to lapse anyway. Isidor Rabi's comment was that Oppenheimer was merely a government consultant at the time anyway and that if the government "didn't want to consult the guy, then don't consult him."

During his hearing, Oppenheimer testified willingly on the left-wing behavior of many of his scientific colleagues. Had Oppenheimer's clearance not been stripped then he might have been remembered as someone who had "named names" to save his own reputation. As it happened, Oppenheimer was seen by most of the scientific community as a martyr to McCarthyism
McCarthyism
McCarthyism is the practice of making accusations of disloyalty, subversion, or treason without proper regard for evidence. The term has its origins in the period in the United States known as the Second Red Scare, lasting roughly from the late 1940s to the late 1950s and characterized by...

, an eclectic liberal who was unjustly attacked by warmongering enemies, symbolic of the shift of scientific creativity from academia into the military. Wernher von Braun
Wernher von Braun
Wernher Magnus Maximilian, Freiherr von Braun was a German rocket scientist, aerospace engineer, space architect, and one of the leading figures in the development of rocket technology in Nazi Germany during World War II and in the United States after that.A former member of the Nazi party,...

summed up his opinion about the matter with a quip to a Congressional committee: "In England, Oppenheimer would have been knighted."

In a seminar at the Woodrow Wilson Institute on May 20, 2009, based on an extensive analysis of the Vassiliev notebooks taken from the KGB archives, John Earl Haynes
John Earl Haynes
John Earl Haynes is an American historian who is a specialist in 20th century political history in the Manuscript Division of the Library of Congress...

, Harvey Klehr
Harvey Klehr
Harvey E. Klehr is a professor of politics and history at Emory University; he is known for his books on the subject of the American Communist movement, and on Soviet espionage in America ....

and Alexander Vassiliev
Alexander Vassiliev
Alexander Vassiliev is a Russian journalist, writer, and espionage historian living in London. A former officer in the Soviet Committee for State Security , Vassiliev is known for his two books based upon KGB archival documents: Spies: The Rise and Fall of the KGB in America, co-authored with John...

confirmed that Oppenheimer never was involved in espionage for the Soviet Union. The KGB tried repeatedly to recruit him, but was never successful; Oppenheimer did not betray the United States. In addition, he had several persons removed from the Manhattan project who had sympathies to the Soviet Union.

## Final years

Starting in 1954, Oppenheimer spent several months of the year living on the island of St. John in the Virgin Islands
Virgin Islands
The Virgin Islands are the western island group of the Leeward Islands, which are the northern part of the Lesser Antilles, which form the border between the Caribbean Sea and the Atlantic Ocean...

. In 1957, he purchased a 2 acre (0.809372 ha) tract of land on Gibney Beach
Gibney Beach
Gibney Beach is a stretch of white sandy beach located on Hawksnest Bay on St John Island in the United States Virgin Islands. There is vibrant wildlife both on the beach and in the bay...

, where he built a spartan home on the beach. He spent a considerable amount of time sailing with his daughter Toni and wife Kitty.

Increasingly concerned about the potential danger to humanity arising from scientific discoveries, Oppenheimer joined with Albert Einstein
Albert Einstein
Albert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...

, Bertrand Russell
Bertrand Russell
Bertrand Arthur William Russell, 3rd Earl Russell, OM, FRS was a British philosopher, logician, mathematician, historian, and social critic. At various points in his life he considered himself a liberal, a socialist, and a pacifist, but he also admitted that he had never been any of these things...

, Joseph Rotblat
Joseph Rotblat
Sir Joseph Rotblat, KCMG, CBE, FRS , was a Polish-born, British-naturalised physicist.His work on nuclear fallout was a major contribution to the agreement of the Partial Test Ban Treaty...

and other eminent scientists and academics to establish what would eventually become the World Academy of Art and Science
World Academy of Art and Science
The World Academy of Art and Science is an international non-governmental scientific organization, an informal and non-official world network of individual fellows elected for distinguished accomplishments in the fields of natural and social sciences, arts and the humanities...

in 1960. Significantly, after his public humiliation, he did not sign the major open protests against nuclear weapons of the 1950s, including the Russell–Einstein Manifesto of 1955, nor, though invited, did he attend the first Pugwash Conferences on Science and World Affairs
Pugwash Conferences on Science and World Affairs
The Pugwash Conferences on Science and World Affairs is an international organization that brings together scholars and public figures to work toward reducing the danger of armed conflict and to seek solutions to global security threats...

in 1957.

However, in his speeches and public writings, Oppenheimer continually stressed the difficulty of managing the power of knowledge in a world in which the freedom of science to exchange ideas was more and more hobbled by political concerns. Oppenheimer delivered the Reith Lectures on the BBC
BBC
The British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff...

in 1953, which were subsequently published as Science and the Common Understanding. In 1955 Oppenheimer published The Open Mind, a collection of eight lectures that he had given since 1946 on the subject of nuclear weapons and popular culture. Oppenheimer rejected the idea of nuclear gunboat diplomacy. "The purposes of this country in the field of foreign policy," he wrote, "cannot in any real or enduring way be achieved by coercion." In 1957 the philosophy and psychology departments at Harvard invited Oppenheimer to deliver the William James Lectures
William James Lectures
The William James Lectures are a series of invited lectureships at Harvard University sponsored by the Departments of Philosophy and Psychology, who alternate in the selection of speakers. The series was created in honor of the American Pragmatist philosopher William James, a former faculty member...

. An influential group of Harvard alumni led by Edwin Ginn
Edwin Ginn
Edwin Ginn , American publisher and philanthropist.In 1838, Ginn was born to a poor family who lived on a small farm near Orland, Maine. At age twenty-four he graduated from Tufts University. After graduation, Ginn had a career selling schoolbooks that became extremely lucrative...

that included Archibald Roosevelt
Archibald Roosevelt
Archibald Bulloch "Archie" Roosevelt , the fifth child of U.S. President Theodore Roosevelt, was a distinguished U.S. Army officer and commander of U.S. forces in both World War I and II. In both conflicts he was wounded. He earned the Croix de guerre and Silver Star with Oak Leaf Cluster,...

protested against the decision. Some 1,200 people packed into Sanders Theatre to hear Oppenheimer's six lectures, entitled "The Hope of Order". Oppenheimer delivered the Whidden Lectures
Whidden Lectures
The Whidden Lectures are a lecture series at McMaster University, founded in 1954 by E. Carey Fox. They commemorate Howard P. Whidden, who was Chancellor of the university from 1923 to 1941. They were first given in 1956. Many of the lectures have been published in book form, by Oxford University...

at McMaster University
McMaster University
McMaster University is a public research university whose main campus is located in Hamilton, Ontario, Canada. The main campus is located on of land in the residential neighbourhood of Westdale, adjacent to Hamilton's Royal Botanical Gardens...

in 1962, and these were published in 1964 as The Flying Trapeze: Three Crises for Physicists.
Deprived of political power, Oppenheimer continued to lecture, write and work on physics. He toured Europe and Japan, giving talks about the history of science, the role of science in society, and the nature of the universe. In September 1957, France made him an Officer of the Legion of Honor, and on May 3, 1962, he was elected a Foreign Member of the Royal Society in Britain. At the urging of many of Oppenheimer's political friends who had ascended to power, President John F. Kennedy
John F. Kennedy
John Fitzgerald "Jack" Kennedy , often referred to by his initials JFK, was the 35th President of the United States, serving from 1961 until his assassination in 1963....

awarded Oppenheimer the Enrico Fermi Award
Enrico Fermi Award
The Enrico Fermi Award is an award honoring scientists of international stature for their lifetime achievement in the development, use, or production of energy. It is administered by the U.S. government's Department of Energy...

in 1963 as a gesture of political rehabilitation. Edward Teller, the winner of the previous year's award, had also recommended Oppenheimer receive it, in the hope that it would heal the rift between them. A little over a week after Kennedy's assassination, his successor, President Lyndon Johnson, presented Oppenheimer with the award, "for contributions to theoretical physics as a teacher and originator of ideas, and for leadership of the Los Alamos Laboratory and the atomic energy program during critical years." Oppenheimer told Johnson: "I think it is just possible, Mr. President, that it has taken some charity and some courage for you to make this award today." The rehabilitation implied by the award was partly symbolic, as Oppenheimer still lacked a security clearance and could have no effect on official policy, but the award came with a \$50,000 tax-free stipend, and its award outraged many prominent Republicans in Congress. The late President Kennedy's widow Jacqueline, still living in the White House, made it a point to meet with Oppenheimer to tell him how much her husband had wanted him to have the medal. While still a senator in 1959, Kennedy had been instrumental in voting to narrowly deny Oppenheimer's enemy Lewis Strauss a coveted government position as Secretary of Commerce, effectively ending Strauss' political career. This was partly due to lobbying by the scientific community on behalf of Oppenheimer.

A chain smoker since early adulthood, Oppenheimer was diagnosed with throat cancer
Head and neck cancer refers to a group of biologically similar cancers that start in the upper aerodigestive tract, including the lip, oral cavity , nasal cavity , paranasal sinuses, pharynx, and larynx. 90% of head and neck cancers are squamous cell carcinomas , originating from the mucosal lining...

in late 1965 and, after inconclusive surgery, underwent unsuccessful radiation treatment and chemotherapy
Chemotherapy
Chemotherapy is the treatment of cancer with an antineoplastic drug or with a combination of such drugs into a standardized treatment regimen....

late in 1966. He fell into a coma on February 15, 1967, and died at his home in Princeton, New Jersey
Princeton, New Jersey
Princeton is a community located in Mercer County, New Jersey, United States. It is best known as the location of Princeton University, which has been sited in the community since 1756...

, on February 18, aged 62. A memorial service was held at Alexander Hall at Princeton University a week later, which was attended by 600 of his scientific, political and military associates, including Bethe, Groves, Kennan, Lilienthal, Rabi, Smyth and Wigner. His brother Frank and the rest of his family were there, as was the historian Arthur Meier Schlesinger Jr., the novelist John O'Hara
John O'Hara
John Henry O'Hara was an American writer. He initially became known for his short stories and later became a best-selling novelist whose works include Appointment in Samarra and BUtterfield 8. He was particularly known for an uncannily accurate ear for dialogue...

, and George Balanchine
George Balanchine
George Balanchine , born Giorgi Balanchivadze in Saint Petersburg, Russia, to a Georgian father and a Russian mother, was one of the 20th century's most famous choreographers, a developer of ballet in the United States, co-founder and balletmaster of New York City Ballet...

, the director of the New York City Ballet
New York City Ballet
New York City Ballet is a ballet company founded in 1948 by choreographer George Balanchine and Lincoln Kirstein. Leon Barzin was the company's first music director. Balanchine and Jerome Robbins are considered the founding choreographers of the company...

. Bethe, Kennan and Smyth gave brief eulogies. Oppenheimer was cremated and his ashes were placed in an urn. Kitty took his ashes to St. John and dropped the urn into the sea off the coast, within sight of the beach house.

Upon the death of Kitty Oppenheimer, who died of an intestinal infection complicated by pulmonary embolism
Pulmonary embolism
Pulmonary embolism is a blockage of the main artery of the lung or one of its branches by a substance that has travelled from elsewhere in the body through the bloodstream . Usually this is due to embolism of a thrombus from the deep veins in the legs, a process termed venous thromboembolism...

in October 1972, Oppenheimer's ranch in New Mexico was inherited by their son Peter, and the beach property was inherited by their daughter Toni. Toni was refused security clearance for her chosen vocation as a United Nations translator after the FBI brought up the old charges against her father. Three months following the end of her second marriage, she committed suicide by hanging in the beach house in January 1977 and left it in her will to "the people of St. John for a public park and recreation area." The original house, built too close to the coast, succumbed to a hurricane, but today, the Virgin Islands Government maintains a Community Center in the area.

## Legacy

When Oppenheimer was ejected from his position of political influence in 1954, he symbolized for many the folly of scientists thinking they could control how others would use their research. He has also been seen as symbolizing the dilemmas involving the moral responsibility of the scientist in the nuclear world. The hearings were motivated both by politics, as Oppenheimer was seen as a representative of the previous administration, and by personal considerations stemming from his enmity with Lewis Strauss. The ostensible reason for the hearing and the issue that aligned Oppenheimer with the liberal intellectuals, Oppenheimer's opposition to hydrogen bomb development, was based as much on technical grounds as on moral ones. Once the technical considerations were resolved
History of the Teller–Ulam design
This article chronicles the history and origins of the Teller-Ulam design, the technical concept behind modern thermonuclear weapons, also known as the hydrogen bomb.-Teller's "Super":...

, he supported Teller's hydrogen bomb because he believed that the Soviet Union would inevitably construct one too. Rather than consistently oppose the "Red-baiting" of the late 1940s and early 1950s, Oppenheimer testified against some of his former colleagues and students, both before and during his hearing. In one incident, his damning testimony against former student Bernard Peters was selectively leaked to the press. Historians have interpreted this as an attempt by Oppenheimer to please his colleagues in the government and perhaps to divert attention from his own previous left-wing ties and those of his brother. In the end it became a liability when it became clear that if Oppenheimer had really doubted Peters' loyalty, his recommending him for the Manhattan Project was reckless, or at least contradictory.
Popular depictions of Oppenheimer view his security struggles as a confrontation between right-wing militarists (symbolized by Teller) and left-wing intellectuals (symbolized by Oppenheimer) over the moral question of weapons of mass destruction. The question of the scientists' responsibility toward humanity inspired Bertolt Brecht
Bertolt Brecht
Bertolt Brecht was a German poet, playwright, and theatre director.An influential theatre practitioner of the 20th century, Brecht made equally significant contributions to dramaturgy and theatrical production, the latter particularly through the seismic impact of the tours undertaken by the...

's drama Galileo (1955), left its imprint on Friedrich Dürrenmatt
Friedrich Dürrenmatt
Friedrich Dürrenmatt was a Swiss author and dramatist. He was a proponent of epic theatre whose plays reflected the recent experiences of World War II. The politically active author's work included avant-garde dramas, philosophically deep crime novels, and often macabre satire...

's Die Physiker
Die Physiker
The Physicists is a satiric drama often recognized as the most impressive yet most easily understood work of the Swiss writer Friedrich Dürrenmatt...

, and is the basis of the opera Doctor Atomic
Doctor Atomic
Doctor Atomic is an opera by the contemporary American composer John Adams, with libretto by Peter Sellars. It premiered at the San Francisco Opera on 1 October 2005. The work focuses on the great stress and anxiety experienced by those at Los Alamos while the test of the first atomic bomb was...

by John Adams (2005), which was commissioned to portray Oppenheimer as a modern-day Faust
Faust
Faust is the protagonist of a classic German legend; a highly successful scholar, but also dissatisfied with his life, and so makes a deal with the devil, exchanging his soul for unlimited knowledge and worldly pleasures. Faust's tale is the basis for many literary, artistic, cinematic, and musical...

. Heinar Kipphardt's play In the Matter of J. Robert Oppenheimer, after appearing on West German television, had its theatrical release in Berlin and Munich in October 1964. Oppenheimer's objections resulted in an exchange of correspondence with Kipphardt, in which the playwright offered to make corrections but defended the play. It premiered in New York in June 1968, with Joseph Wiseman
Joseph Wiseman
Joseph Wiseman was a Canadian theater and film actor, best known for starring as the titular antagonist of the first James Bond film, Dr. No, his role as Manny Weisbord on Crime Story, and his career on Broadway...

in the Oppenheimer role. New York Times theater critic Clive Barnes
Clive Barnes (critic)
Clive Alexander Barnes, CBE was a British-born American writer and critic. From 1965 to 1977 he was the dance and theater critic for the New York Times, the most powerful position he had held, since its theater critics' reviews historically have had great influence on the success or failure of...

called it an "angry play and a partisan play" that sided with Oppenheimer but portrayed the scientist as a "tragic fool and genius". Oppenheimer had difficulty with this portrayal. After reading a transcript of Kipphardt's play soon after it began to be performed, Oppenheimer threatened to sue the playwright, decrying "improvisations which were contrary to history and to the nature of the people involved."
Later Oppenheimer told an interviewer:
The 1980 BBC TV serial Oppenheimer
Oppenheimer (TV miniseries)
Oppenheimer is a television serial about J. Robert Oppenheimer, produced by the BBC. It began broadcast in the United Kingdom on 29 October 1980 and in the United States on 11 May 1982...

, starring Sam Waterston
Sam Waterston
Samuel Atkinson "Sam" Waterston is an American actor and occasional producer and director. Among other roles, he is noted for his Academy Award-nominated portrayal of Sydney Schanberg in 1984's The Killing Fields, and his Golden Globe- and Screen Actors Guild Award-winning portrayal of Jack McCoy...

, won three BAFTA Television Awards. The Day After Trinity
The Day After Trinity
The Day After Trinity is a 1980 documentary film directed and produced by Jon H. Else in association with KTEH public television in San Jose, California. The film tells the story of J...

, a 1980 documentary about J. Robert Oppenheimer and the building of the atomic bomb, was nominated for an Academy Award and received a Peabody Award
Peabody Award
The George Foster Peabody Awards recognize distinguished and meritorious public service by radio and television stations, networks, producing organizations and individuals. In 1939, the National Association of Broadcasters formed a committee to recognize outstanding achievement in radio broadcasting...

. In addition to his use by authors of fiction, Oppenheimer's life has been explored in numerous biographies, including American Prometheus: The Triumph and Tragedy of J. Robert Oppenheimer (2005) by Kai Bird
Kai Bird
Kai Bird is an American Pulitzer Prize-winning author and columnist, best known for his biographies of political figures.-Personal life:Bird was born in 1951 in Eugene, Oregon. His father was a U.S. Foreign Service officer, and he spent his childhood in Jerusalem, Beirut, Dhahran, Cairo and Bombay...

and Martin J. Sherwin
Martin J. Sherwin
Martin J. Sherwin is a Pulitzer Prize-winning American historian. His scholarship mostly concerns the history of the development of atomic energy and nuclear proliferation....

which won the Pulitzer Prize for Biography or Autobiography
Pulitzer Prize for Biography or Autobiography
The Pulitzer Prize for Biography or Autobiography has been presented since 1917 for a distinguished biography or autobiography by an American author.-1910s:* 1917: Julia Ward Howe by Laura E...

for 2006. A centennial conference and exhibit were held in 2004 at Berkeley, with the proceedings of the conference published in 2005 as Reappraising Oppenheimer: Centennial Studies and Reflections. His papers are in the Library of Congress
Library of Congress
The Library of Congress is the research library of the United States Congress, de facto national library of the United States, and the oldest federal cultural institution in the United States. Located in three buildings in Washington, D.C., it is the largest library in the world by shelf space and...

.

As a scientist, Oppenheimer is remembered by his students and colleagues as being a brilliant researcher and engaging teacher, the founder of modern theoretical physics in the United States. Because his scientific attentions often changed rapidly, he never worked long enough on any one topic to merit the Nobel Prize, although his investigations contributing to the theory of black holes may have warranted the prize had he lived long enough to see them brought into fruition by later astrophysicists. An asteroid, 67085 Oppenheimer
67085 Oppenheimer
67085 Oppenheimer is a main-belt asteroid discovered on January 4, 2000 by S. Sposetti at Gnosca.-External links:*...

, was named in his honor, as was the lunar crater Oppenheimer
Oppenheimer (crater)
Oppenheimer is a large lunar crater that lies on the Far side of the Moon. It lies along the western outer ampart of the immense walled plain Apollo. Nearby features of note include the dark-floored crater Maksutov to the southwest, and Davisson to the west-southwest...

.

As a military and public policy advisor, Oppenheimer was a technocratic
Technocracy (bureaucratic)
Technocracy is a form of government where technical experts are in control of decision making in their respective fields. Economists, engineers, scientists, health professionals, and those who have knowledge, expertise or skills would compose the governing body...

leader in a shift in the interactions between science and the military and the emergence of "Big Science
Big Science
Big Science is a term used by scientists and historians of science to describe a series of changes in science which occurred in industrial nations during and after World War II, as scientific progress increasingly came to rely on large-scale projects usually funded by national governments or groups...

". During World War II, scientists became involved in military research to an unprecedented degree. Because of the threat fascism
Fascism
Fascism is a radical authoritarian nationalist political ideology. Fascists seek to rejuvenate their nation based on commitment to the national community as an organic entity, in which individuals are bound together in national identity by suprapersonal connections of ancestry, culture, and blood...

posed to Western civilization, they volunteered in great numbers both for technological and organizational assistance to the Allied effort, resulting in such powerful tools as radar