Oppenheimer, J. Robert

Born April 22, 1904
New York, New York
Died February 18, 1967
Princeton, New Jersey
American physicist

J. Robert Oppenheimer's brilliant research in the field of quantum mechanics (the study of the energy of atomic particles) led to his selection as the director of the weapons laboratory at Los Alamos, New Mexico. There, scientists from all over the world worked secretly to develop a powerful atomic bomb that, it was hoped, would end World War II. Oppenheimer was known not only for the important role he played in the Manhattan Project, but also for his work as a researcher and teacher. After the war, he advised the government on how best to use nuclear energy and weapons.

A bright and curious boy

Oppenheimer was born into a wealthy, cultured family. His father, Julius Oppenheimer, had emigrated from Germany as a young man and had built a successful textile importing company. His mother, Ella Friedman, was a painter who loved art and music. The family lived in a large apartment in New York City, but spent their summers on nearby Long Island.

Oppenheimer's great intelligence and curiosity were obvious early in his life. By the time he was eleven he had put together a huge rock collection and became the youngest member ever admitted to the New York Mineralogical Society; at twelve, he presented a paper to the society. Oppenheimer attended the liberal, academically challenging Ethical Culture School in New York City. After graduating he went to Europe for the summer, but there he contracted dysentery (a severe intestinal illness) and had to spend the next year recovering.

A young star in the world of physics

In 1922, Oppenheimer entered Harvard University, where, he later said (as quoted in Current Biography) he "lived in the [library] stacks, just raided the place intellectually." He studied a wide range of subjects—including science and foreign languages—but he was most drawn to physics, and that became his major. Oppenheimer graduated summa cum laude (with highest honors) in only three years.

Oppenheimer graduated from college at a very exciting time in the field of physics, when many discoveries were being made. He decided to go to Europe to continue his study of theoretical physics. He started at the Cavendish Laboratory at Cambridge University in England. In his first paper as a graduate student, Oppenheimer explained aspects of the behavior of the molecule (the smallest part of a substance that has all the properties of that substance and is made up of one or more atoms). In 1926, Oppenheimer moved to the University of Göttingen in Germany, where he worked with a famous physicist, Max Born, to develop the "Born-Oppenheimer Theory" of molecular activity.

Oppenheimer earned his doctorate in 1927, and went on to conduct more research in Leiden, Holland, and Zurich, Switzerland. In Switzerland he worked closely with another famous scientist, Wolfgang Pauli. During these years of study, Oppenheimer showed how quickly he could grasp and analyze ideas and how well he could draw connections between theories and detect problems.

A popular, inspiring teacher

On his return from Europe, ten universities offered Oppenheimer teaching positions. In 1928 he accepted two of them, the University of California at Berkeley and the California Institute of Technology (Cal Tech) at Pasadena. For the next thirteen years he divided his time between these two schools, doing his own research as well as teaching. During this period he established Berkeley as a major American center for the study of quantum physics (the study of the energy of atomic particles).

Oppenheimer also gained a reputation as an excellent teacher. His classes moved at a rapid pace, as he stood at the blackboard with his ever-present cigarette in one hand and a piece of chalk in the other. He sparked many students' interest in theoretical physics, and some of them admired him so much that they imitated his mannerisms (such as his habit, developed during his time in Germany, of saying "Ja! Ja! Ja!" to encourage discussion) and followed him from one campus to another, sometimes repeating courses they'd already taken.

Although Oppenheimer continued to have a wide range of interests, including the other sciences, literature, and art, he lived a sheltered life (he had no telephone, did not read newspapers, and did not even vote) until the middle of the 1930s. Then some developments in the world, such as the hard economic times many people were experiencing and the rise of harsh dictators around the world, began to catch his notice. He became involved with several groups working for social reform, including some that had ties to the Communist Party. Oppenheimer, however, never became a Communist.

The world moves toward war

As World War II loomed, science made discoveries that would change the face of warfare. In 1934, Italian physicist Enrico Fermi had devised a way to bombard uranium (a radioactive metallic element) with neutrons (a particle from the nucleus or center of an atom) to create a reaction called nuclear fission. Many scientists believed that if a large enough amount of uranium—called a "critical mass"—could be used, a chain reaction would occur, instantly setting off a huge explosion of energy. Various physics laboratories were studying the possibility of using this reaction in a military weapon—an atomic bomb.

After the United States had entered World War II on December 7, 1941, Allied intelligence operations (spying activities of the countries fighting together against Germany, Japan, and Italy, including the United States, Great Britain, and the Soviet Union) learned that the Germans were also working on an atomic bomb. President Franklin D. Roosevelt (1882-1945; see entry) decided that the United States must immediately start its own atomic research program, which would be called the Manhattan Project.

The Manhattan Project takes off

Oppenheimer was recruited for the program not because he was particularly interested in it but because he was widely recognized as a brilliant, pioneering physicist. He took part in some of the first meetings to discuss the possible use of an atomic bomb, and in early 1942 he was asked to direct research on the bomb at Berkeley. Soon the government put the project under the control of the U.S. Army, and Colonel (later General) Leslie Groves was put in charge.

Development of the bomb took place at a number of laboratories in different places. Oppenheimer recommended that a single lab be set up, where scientists could work more closely and in secret. It was Groves who decided that Oppenheimer—despite his lack of administrative and management experience—should direct the lab; he told his doubtful colleagues, "we (are) not going to find a better man."

Oppenheimer suggested that the laboratory be built at Los Alamos, New Mexico, near an area where he had often vacationed. The area was geographically isolated and transportation was difficult, but this would help ensure the secrecy the project required. Oppenheimer supervised the construction of the huge complex (which, by the end of World War II, housed 5,000 workers) and the collection of equipment needed for research. He had to put together a team of leading scientists, all with different, sometimes difficult personalities, and get them to work together in harmony. And he had to convince them to bring their families to Los Alamos and stay until the war was over.

Oppenheimer accomplished all these things, establishing at Los Alamos an atmosphere of hard work and a free exchange of information. He also opened up his own home as an informal social center, where he and his wife, Katherine (whom he had married in 1940), often entertained the laboratory's scientists and staff.

Creating and testing an atomic bomb

The biggest problem the Los Alamos physicists had to solve was how to achieve critical mass—how to bring two pieces of uranium together quickly enough to create a chain reaction and produce an explosion. Another stumbling block was the length of time it took to refine uranium to the required purity; this process took place in two factories in Oak Ridge, Tennessee, and Hanford, Washington, but production was moving more slowly than expected.

By the summer of 1945, the technical problems had finally been resolved, and the atomic bomb was ready for testing. The test took place on July 16 on the Alamogordo Bombing Range. At 5:30 A.M. the bomb was detonated, setting off a flood of white light and a loud roaring noise, and causing a ball of fire to raise an immense cloud of sand and debris 40,000 feet into the air.

"The Shatterer of Worlds"

Watching the tremendous explosion from five miles away, Oppenheimer was reminded of two lines from the Bhagavad-Gita, the Hindu sacred text that he had read in its original Sanskrit (one of eight languages he could read). One line referred to the "radiance of a thousand suns," and the other said, "I am become death, the Shatterer of Worlds." Like others present at the test, Oppenheimer's feelings were a mixture of pride in the success of their efforts, terror at the bomb's immense destructive power, and anxiety about what it meant for the future.

By this time, Germany had already surrendered and the war in Europe was over. But it seemed that Japan, despite major losses and very bleak prospects, would continue no matter the odds. Oppenheimer met with three other scientists (Ernest Lawrence, Enrico Fermi, and Arthur Compton) to discuss whether the United States should use the atomic bomb against Japan. The only alternative to the bomb, the U.S. government asserted, was to invade Japan, which would cost many American lives. On the other hand, the bomb could be dropped on a military target but would undoubtedly kill many Japanese civilians.

Although Oppenheimer would later regret his decision (claiming that the killing of civilians could and should have been avoided), he and the other scientists recommended that the United States use the atomic bomb against Japan. The final decision was made by President Harry S. Truman (1884-1975; see entry), who gave the plan his approval.

On August 6, 1945, the first bomb, nicknamed "Little Boy," was dropped on Hiroshima. Instantly, the city was destroyed: from 78,000 to 80,000 people were killed and 60,000 buildings were demolished. Over the next weeks and months, thousands more people would die of the sickness caused by the radioactive particles released by the explosion. On August 9, a second bomb ("Fat Man") was dropped on Nagasaki, killing between 25,000 and 40,000 people that day and many more later, as radiation sickness again took its toll. Japan surrendered on August 14, ending World War II.

Advisor on atomic energy and weapons

The existence of the atomic bomb had been kept secret until the Hiroshima bombing. News of the bomb made Oppenheimer famous as the so-called "Father of the A-Bomb." secretary of war Henry Stimson claimed that "the development of the bomb has been largely due to his genius and the inspiration and leadership he has given to his associates." Yet Oppenheimer himself had very serious concerns about the bomb, and wanted to make sure it was properly controlled and used only to prevent wars.

After the war, Oppenheimer was asked to advise the government on how to control and manage atomic energy and weapons. In 1947 he was appointed to serve on the General Advisory Committee of the Atomic Energy Commission, which had been established the previous year when it was decided that atomic energy should be under civilian, rather than military, control. Oppenheimer served in this position until 1952.

Building a research center

In 1947, Oppenheimer became the director of the Institute for Advanced Study at Princeton University, overseeing its development into a first-rate physics research center. Under his leadership the institute's population grew, attracting many young scientists who enjoyed the lively atmosphere in which new ideas were discussed and tested. In describing the institute's work, Oppenheimer commented, "What we do not know we try to explain to each other."

During this period, Oppenheimer wrote and lectured on atomic energy, and also on the relationship between the scientist and society. His interest in how to make science understandable to those with little background in it was the topic of his 1954 book, Science and the Common Understanding.

Security clearance withdrawn

Despite the praise Oppenheimer received for his job as director of the Manhattan Project, he had made some enemies during his career. His opposition to the H-bomb (a much more powerful weapon than the atomic bomb that uses hydrogen instead of uranium or plutonium) had angered the scientists who backed it, especially its developer, Robert Teller. Oppenheimer believed the United States should focus not on building a bigger bomb but on arms treaties. The United States and the Soviet Union were, he said, like "two scorpions in a bottle, each capable of killing the other but only at the risk of its own life."

During the mid-1950s, anti-Communist (communism is the political system that features communal or group ownership of property) fever was sweeping the country. Senator Joseph McCarthy and others crusaded to rid the government of those they considered Communist sympathizers. In 1954, Oppenheimer was informed that his security clearance was being withdrawn. He asked for a hearing so that he could defend himself. At the three-week hearing, Oppenheimer's past connections with communist-related groups were brought up to discredit him, and his failure to support the H-bomb program was criticized. The final result was that even though he was undoubtedly a "loyal citizen," his security clearance would still be canceled.

The scientific community was outraged by what had happened to Oppenheimer, and they openly supported and praised him. Although he never again worked for the government, he continued his work at Princeton. In 1963, the Atomic Energy Commission gave Oppenheimer the important Enrico Fermi Award, which came with a $50,000 prize. Presented to him by President Johnson, the award was seen by many as the government's way of making amends with Oppenheimer. Four years later, he died of cancer at age sixty-two.

Where to Learn More

Books

Driemen, J.E. Atomic Dawn: A Biography of Robert Oppenheimer. Minneapolis, MN: Dillon Press, 1989.

Goodchild, Peter. J. Robert Oppenheimer: Shatterer of Worlds. New York:Fromm International, 1985.

Kunetka, James W. Oppenheimer: The Years of Risk. Englewood Cliffs, NJ:Prentice-Hall, 1982.

Larsen, Rebecca. Oppenheimer and the Atomic Bomb. New York: Franklin Watts, 1988.

Periodicals

"Brotherhood of the Bomb: Two Flinty Physicists Struggle Over Their Terrifying Legacy." U.S. News & World Report Special Report: Masters of Discovery: The Great Inventions of the 20th Century (August 17, 1998): 64.

J. Robert Oppenheimer headed the Manhattan Project—the successful effort by a group of scientists to build the first atomic bomb, which would bring the war to a swift close when used against the Japanese.

A World-Famous Physicist Joins the Manhattan Project

One of the most famous scientists to take in the Manhattan Project was the Italian physicist Enrico Fermi, who had defected (to abandon one's country to become a citizen of a new country) to the United States after winning the Nobel Prize in 1938.

Born in Rome, Italy on September 29, 1901, Fermi grew into a talented, bright teenager who learned more about physics while he was still in high school than many university graduate students. He earned his Ph.D. in physics in Italy when he was only 21, then went on to study at the German universities of Göttingen and Leiden. In 1924 he came back to Italy and became a professor at the University of Florence.

While teaching in Florence, Fermi wrote an important paper about the actions of subatomic particles. Now recognized as a leader in physics, Fermi was named to the newly created chair of theoretical physics at the University of Rome, where he worked over the next six years with a number of leading physicists and brilliant students.

During the early 1930s, while studying the atomic nucleus, Fermi discovered a new kind of particle called a "neutrino" and a new kind of force called "weak force." Later he experimented with bombarding atoms in various chemical elements with neutrons, showing that this process could produce radioactive forms (unstable atoms that give off particles and energy). Later he discovered that if a uranium atom was bombarded with neutrons it would split, producing a reaction called nuclear fission that releases huge amounts of energy.

In 1938 Fermi was awarded the Nobel Prize for his work with neutron bombardment, and after accepting his award in Sweden he and his family didn't return to Italy but went to the United States. His own country's Fascist dictator Benito Mussolini (1883-1945; see entry) was an ally of Germany's dictator Adolf Hitler, who had begun harsh measures against Jews, and Fermi's wife was Jewish. Fermi now became a professor of physics at Columbia University in New York City.

In August 1939 President Franklin D. Roosevelt (1882-1945; see entry) received a letter from Hungarian-American physicist Leo Szilard and world-renowned physicist Albert Einstein warning that nuclear weapons (which would make use of the powerful energy released by nuclear fission) were going to be developed and used by Germany. Roosevelt's response was to set up the Manhattan Project so that American scientists could explore the possibility of making an atomic bomb.

Working in his lab under Columbia's squash courts on December 2, 1942, Fermi produced the world's first self-sustaining nuclear chain reaction. He continued his work on nuclear fission at a Chicago laboratory for two years, but in 1944 he and his wife (both new citizens of the United States) moved to Los Alamos, New Mexico, so that Fermi could join the scientists working under the direction of Robert Oppenheimer.

Fermi was put in charge of his own division, which was assigned to resolve any special problems that might arise as work on the first atomic bombs continued. The bombs were finally tested and dropped on Japan, effectively ending the war in Asia. Fermi returned to the University of Chicago, where he remained as a professor and researcher for the rest of his life. He received the Civilian Medal of Merit in 1946 for his work on the Manhattan Project. After his death in 1954, the U.S. Atomic Energy Commission named Fermi the first recipient of its Enrico Fermi Award.