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A digitally colourised photograph of Robert Oppenheimer

The father of the atomic bomb: Who was Robert Oppenheimer?

Image Credits: Public Domain (Ed Westcott) / | Above (Left): A digitally colourised photograph of Robert Oppenheimer (Right) A photograph of an atomic bomb called 'Little Boy'

During World War Two, J. Robert Oppenheimer led a team of scientists who were tasked with creating a weapon that would alter the course of the war. What they built changed the world forever and continues to shape the geopolitical landscape in the 21st century.

Known as the ‘father of the atomic bomb’, Oppenheimer was a remarkable theoretical physicist whose exceptional scientific brilliance was clear from a young age. Although his career was much lauded, his relationship with the American government and military was far from smooth sailing.

Born in New York City on 22nd April 1904 to German Jewish immigrants, Oppenheimer was a natural scientist. An early love of minerals led him to correspond with the New York Mineralogical club who were so impressed with his writings that they invited him to deliver a lecture, unaware he was just 12-years-old at the time.

He attended Harvard University to study chemistry in 1922. Although he graduated top of his class three years later, a love of physics drew the young Oppenheimer down a different scientific path.

He then travelled to Cambridge in the UK to begin his graduate work in physics. Working at Cavendish Laboratory under Nobel Prize winner J.J. Thomson - the man who detected the electron – Oppenheimer began his atomic research.

A year later, Oppenheimer found himself in Germany studying at the University of Göttingen, one of the world’s leading centres for theoretical physics. He’d been invited there by Max Born, the director of the Institute of Theoretical Physics, and was soon mingling with future world-renowned scientists.

During his time in Germany, he published many papers contributing to the newly developed quantum theory. One notable piece of work was the Born-Oppenheimer approximation for molecular wave functions, an important contribution to the quantum molecular theory that gained much fame within the scientific world.

By 1927, Oppenheimer had received his doctorate and undertaken professorships at both the University of California, Berkeley, and the California Institute of Technology. He spent the next 13 years commuting between the two schools conducting important research in a multitude of scientific fields including nuclear physics, quantum field theory, and astrophysics.

Oppenheimer and another of his students, Hartland Snyder, produced a paper in 1939 that predicted the existence of black holes. This, along with the Born-Oppenheimer approximation, remains two of his most cited papers. Although he was nominated for a Nobel Prize three times, he never won one.

Oppenheimer began to awaken politically in the 1930s and realised that Hitler's Nazi Germany could well develop the world's first nuclear weapon. As war broke out across Europe in September 1939, America watched with a fearful eye. Oppenheimer eagerly joined the early efforts his country was making to develop a nuclear weapon.

In 1940, Oppenheimer married Katherine ‘Kitty’ Puening, a radical Berkeley student and former Communist Party member. The pair had their first child, Peter, in 1941, and their second, Katherine, was born three years later.

In 1942, General Leslie Groves invited Oppenheimer to become the scientific director of the Manhattan Project, the top-secret U.S. project to develop the atomic bomb. After Oppenheimer had selected a location in Los Alamos, New Mexico, the U.S. Army went about constructing a series of laboratories there.

The best minds in physics across America and Europe were brought to Los Alamos and tasked with creating a bomb like no other the world had ever seen. Oppenheimer’s team of just a few hundred soon grew to several thousand, all under his direction, as American taxpayer money flooded into the project. Although Oppenheimer had little experience managing a project of this scale, he quickly learned the ropes, repaying the faith that General Groves had bestowed upon him.

Just three years after the project began, Oppenheimer and his team were ready to test their atomic bomb. The ‘Trinity’ test was conducted on 16th July 1945 at Alamogordo, New Mexico where an anxious Oppenheimer watched from a control bunker as the world’s first nuclear explosion erupted.

After the bright flash of light, it was observed that Oppenheimer breathed a huge sigh of relief; his team had done it. His first words reportedly were: “I guess it worked.” He later famously recalled that the history-defining moment had brought to mind words from a sacred Hindu text:

“We knew the world would not be the same. A few people laughed, a few people cried. Most people were silent. I remembered the line from the Hindu scripture, the Bhagavad Gita, ‘Now I am become Death, the destroyer of worlds’. I suppose we all thought that, one way or another.”

Less than a month later, America dropped two atomic bombs on the Japanese cities of Hiroshima and Nagasaki, effectively bringing an end to the Second World War. Oppenheimer was said to have been distraught that the bomb was used twice, believing the second bomb was unnecessary.

A few days later, he secured a meeting with President Truman where he expressed his revulsion at Nagasaki, telling the President that he felt there was “blood on [his] hands”. The President had little time for Oppenheimer’s moralistic stance and famously stated to his aides after the meeting, “I never want to see that son of a bitch in this office again.”

After the war, Oppenheimer became a household name and featured on the covers of both Life and Time magazines. In 1947, he became chairman of the General Advisory Committee of the Atomic Energy Commission (AEC). During his time there, Oppenheimer opposed the development of the more powerful hydrogen bomb, a position that put him in the firing line of those who wanted to take a firm stance against the growing Soviet threat.

It wasn’t long before his enemies got their way. Denounced as having Communist sympathies, Oppenheimer was removed from his role at the AEC in 1954 and stripped of all security clearances, effectively losing his political influence at the same time. The move shocked the scientific community, and it took nearly a decade before amends were made.

In 1963, President John F. Kennedy awarded Oppenheimer the Enrico Fermi Award, although President Lyndon B. Johnson presented him with it after JFK’s assassination. The award was not only an apologetic gesture but also one that signified political rehabilitation for the famed scientist.

In his later years, Oppenheimer continued to lobby for international control of nuclear weapons and atomic energy. On 18th February 1967, he died of throat cancer in Princeton, New Jersey, just a year after retiring.