Dr. J. Robert Oppenheimer: Quotes, Biography & the Atomic Bomb

Instructor: Matthew Hill
Although J. Robert Oppenheimer was known as the 'father of the atomic bomb', he became a pacifist in later life. Find out more about this renowned physicist and his work with the Manhattan Project and beyond.

Roots of a Nuclear Physicist

J. Robert Oppenheimer was born in New York City in April 1904 to Jewish immigrants from Germany. His father worked in textiles and his mother was an artist. The bright young Oppenheimer was drawn to science and attended the private Ethical Society Cultural School, after which he studied physics at Harvard. After Harvard, he spent a year at the distinguished Cavendish Laboratory at Cambridge University and then earned his PhD at the University of Gottingen in Germany under the renowned German physicist Max Born. The two collaborated on the Born-Oppenheimer approximation, which dealt with separating nuclear motion and electronic motion in molecules.

Robert Oppenheimer
Robert Oppenheimer

After completing his PhD, Oppenheimer briefly studied as a National Research Council Fellow. Shortly thereafter, he accepted a dual appointment as a research professor at the California Institute of Technology and the University of California at Berkeley, which created the first program in America dedicated to theoretical physics. At Berkeley, his research extended to multiple fields in physics and astrophysics, and in the 1930s he was one of the first to argue for the existence of black holes. In 1940, he married Berkeley student and activist Katherine Harrison with whom he had two sons.

L-R: Albert Einstein and Robert Oppenheimer
Einstein and Oppenheimer

The Manhattan Project

At the start of the Second World War, Germany's nuclear program was advanced, but Adolf Hitler's pogrom against the Jews drove many of his leading scientists to the United States. A group of physicists that included Albert Einstein wrote a letter to President Roosevelt urging him to fund an atomic research program. Preliminary research had already been conducted at several American universities, but FDR decided to centralize the research in a single location under a single director. The project, which started in 1942, was codenamed the Manhattan Project; it became what Oppenheimer was best known for.

General Leslie Groves, the program director, appointed Oppenheimer as the scientific director at the Los Alamos Laboratories in New Mexico. Oppenheimer pulled together a first-class team of scientists to test the possibilities of building a nuclear bomb. Across the country more than 120,000 people worked on the project, though Oppenheimer worked directly over 3,000. In all, nearly $2 billion was spent on the project.

Photo of the Trinity Explosion in Alamagordo, New Mexico
Trinity Explosion

The Atomic Bomb is Born

On July 16, 1945, in Alamogordo, New Mexico, the first ever atomic test was successfully detonated underground. Oppenheimer called the bomb 'Trinity.' A noted Sanskrit scholar, Oppenheimer quoted the following line from the Hindu Bhagavad Gita: 'I have become death, the destroyer of worlds', to capture the mood of the moment. The bomb was originally designed to be used on Nazi Germany, but Germany surrendered before the bombs were ready. On August 6, 1945, the first bomb, named 'Little Boy' was dropped on Hiroshima, and on August 9 the 'Fat Man' was dropped on Nagasaki. Collectively, the two bombs killed over 200,000 people in seconds.

Although it paled in number to the total number killed in conventional bombing campaigns, the speed and intensity in which it did frightened its own creators. Oppenheimer was shaken and later stated that, 'The atomic bomb made the prospect of future war unthinkable. It has led us up those last few steps to the mountain pass; and beyond there is a different country.' In fact, his growing doubts soon got him into trouble.

L-R: Robert Oppenheimer and General Leslie Groves
Oppenheimer and Groves

Late Career Troubles

In 1947, Oppenheimer was appointed head of the General Advisory Committee of the Atomic Energy Commission, which oversaw atomic research. In this role, Oppenheimer increasingly voiced his opposition to developing the newer hydrogen bomb. Over time he grew more reflective on the nature of his work. He once mused, 'When you see something that is technically sweet, you go ahead and do it and you argue about what to do about it only after you have had your technical success. That is the way it was with the atomic bomb.' His point was the scientists were so eager to see if the bomb was scientifically possible that they never bothered to ask whether it should be created in the first place.

L-R: Photo of the Atomic Bombs at Hiroshima and Nagasaki
The Atomic Bombs

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