What was J Robert Oppenheimer's relationship to Albert Einstein?

Across an epic three-hour runtime, a number of Oppenheimer's personal and professional relationships are put under the microscope, with Emily Blunt, Matt Damon, Florence Pugh and Robert Downey Jr among the big names to play key figures in his life.

And one character who plays a pivotal role in the film – even if his actual screen time is relatively limited – is perhaps the most famous scientist of all: Albert Einstein.

The German-born theoretical physicist is played by Tom Conti and has a number of exchanges with Oppenheimer, at one point declaring that the only thing the two have in common is a "disdain for mathematics", and even uttering the crucial closing line of the entire film.

But how close were Einstein and Oppenheimer in real life? Read on for everything you need to know.

What was J Robert Oppenheimer's relationship to Albert Einstein?

As the film suggests, Oppenheimer and Einstein did know each other in real life – and the pair were initially at odds regarding the field of quantum mechanics and the development of nuclear weapons.

They were said to have had their first encounter when Einstein embarked on a round-the-world tour in 1932 and visited Caltech (where Oppenheimer was based at the time), and they would interact several times more before the latter started work on the Manhattan Project.

While working on the Manhattan Project – as is shown in the film – Oppenheimer would occasionally ask Einstein for advice, although the German was not permitted to have a formal role in the project due to being deemed a security risk by the US government.

Although Einstein was always a vocal critic of nuclear weapons, he broke from this stance in 1939 when he signed a letter encouraging the US to begin research in the area – believing at the time that it was necessary to do so before the Germans.

This was a moment that he went on to deeply regret, and he is quoted as having said "Woe is me" following the news that the bomb had been dropped on Hiroshima.

Of course, despite playing the key role in creating the bomb, Oppenheimer himself would go on to become a staunch opponent to the proliferation of nuclear weapons, and it was at this time that he and Einstein could be said to have built up an alliance and become friends.

From 1947, the pair both worked at the Institute for Advanced Study in Princeton, where they remained colleagues until Einstein's death in 1955. During this time, both men played a crucial role in creating what would eventually become the World Academy of Art and Science, while they also continued to voice their opposition to furthering the nuclear program.

In 1965, a decade after Einstein's death, Oppenheimer gave a memorial lecture at UNESCO headquarters during which he made his views on Einstein clear.

He began his speech by declaring: "Though I knew Einstein for two or three decades, it was only in the last decade of his life that we were close colleagues and something of friends" and went on to discredit the notion that Einstein – specifically his writing of the aforementioned letter – was to blame for the advent of "these miserable bombs".

In the same speech, he said of the German: "He was almost wholly without sophistication and wholly without worldliness... there was always with him a wonderful purity at once childlike and profoundly stubborn."

So, while the scenes between Einstein and Oppenheimer shown in Nolan's film might not have happened exactly as they appear, they are certainly representations of the true dynamic between the men and the opinions they held.

Read More

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Oppenheimer is now showing in UK cinemas. Check out more of our Film coverage or visit our TV Guide to see what's on tonight.

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