Go to Home Page
  Library Biographies Julius Robert Oppenheimer

Julius Robert Oppenheimer

J. Robert Oppenheimer was born in New York City on April 22, 1904. After graduating from Harvard and studying under Ernest Rutherford at Cambridge University, Oppenheimer received his Ph.D. in Germany in 1925. In 1929, he returned to the United States to teach at the University of California Berkeley and at Cal Tech.

Upon hearing of discovery of fission in 1939, Oppenheimer immediately grasped the possibility of atomic bombs. In 1941, he was brought into the atomic bomb project and was asked to calculate the critical mass of uranium-235, the amount needed to sustain a chain reaction. The next year he assembled a group of some of the best theoretical physicists in the country to discuss the design of the actual bomb. General Leslie Groves, the army officer in charge of the Manhattan Project, named Oppenheimer the scientific director of the program, and together they decided on Los Alamos, New Mexico, as the site for the nuclear weapons laboratory. Groves said of Oppenheimer, "He's a genius. A real genius...Why, Oppenheimer knows about everything. He can talk to you about anything you bring up. Well not exactly. I guess there are a few things he doesn't know about. He doesn't know anything about sports."

The staff grew from 30 scientists to 5,000, all trying to finish work on the bomb before the

Printer Friendly



More on the Web
Alsos Digital Library for Nuclear Issues
National Academy of Sciences
J. Robert Oppenheimer from PBS American Experience 

Germans did. On the day of the test, Oppenheimer fully realized the enormity of what he had just accomplished. As he stood watching the mushroom cloud, he recalled later, a phrase from the Baghavad Gita, the Hindu scripture, floated through his mind, "I am become death, the destroyer of worlds." This responsibility weighed heavily on his shoulders, and when he met with President Harry Truman in 1946, he exclaimed, "Mr. President, I have blood on my hands."

He set up a research station for the Project at Los Alamos, New Mexico.

Following World War II, Oppenheimer chaired the US Atomic Energy Commission. On December 21, 1953, during the height of anti-communist sentiment in the US, Oppenheimer was accused of delaying the naming of Soviet agents, and also of opposing the building of the hydrogen bomb. Although he was not found guilty of treason, his security access was taken away and his contract as adviser to the Atomic Energy Commission was terminated.

In 1963, President Lyndon B. Johnson presented Oppenheimer with the Enrico Fermi Award of the Atomic Energy Commission. Oppenheimer retired from Princeton in 1966 and died of throat cancer the following year.