The dramatic account of the lethal harnessing of atomic power told in the 2023 blockbuster film Oppenheimer might have been nothing more than science fiction had a two-page letter, dated 2 August 1939, never been written.
"Recent work in nuclear physics made it probable that uranium may be turned into a new and important source of energy," reads a typed letter to US President Franklin D Roosevelt signed by hand by the esteemed physicist Albert Einstein. This energy, he continues, could be used "for the construction of extremely powerful bombs".
Expressing suspicion at Germany's decision to halt uranium sales in occupied Czechoslovakia, the letter was the impetus for a $2 billion top-secret research programme, the "Manhattan Project": a race to beat Germany in the development of atomic weapons. The three-year project, led by physicist Robert Oppenheimer, would propel the US into the nuclear age and lead to one of history's most significant – and destructive – inventions: the atomic bomb.
On 10 September 2024, Einstein's consequential and carefully worded letter will be auctioned at Christie's New York, and is expected to fetch in excess of $4m. Two versions of the letter were drafted: a shorter version, being auctioned by Christie's, and a more detailed version, delivered to the White House by hand, and now in the permanent collection of the Franklin D Roosevelt Library in New York.
"In so many ways, this letter marks a key inflection point in the history of science, technology and humanity," Peter Klarnet, senior specialist for Americana, books and manuscripts at Christie's, tells the BBC. "This is really the first time that the United States government becomes directly financially involved in major scientific research," he adds. "The letter set the ball rolling to allow the United States to take full advantage of the technological transformations that were taking place.
"Dr Bryn Willcock, the programme director for the Department of Politics, Philosophy, and International Relations at Swansea University and a lecturer and researcher in American and Nuclear History, agrees. "Most historical accounts of the origins of the bomb begin with a discussion of the letter," he tells the BBC. "The letter's contents were key to getting direct action from President Roosevelt," he says, emphasising that "the Atomic Heritage Foundation goes as far as to describe the letter… as 'vital' in pushing Roosevelt into undertaking atomic research.
"The award-winning film Oppenheimer, which is based on the story of the Manhattan Project and references the letter in a scene between Oppenheimer and physicist Ernest Lawrence, is expected to fuel additional interest in the auction. "This [letter] is something that has been part of the popular culture from 1945 onwards, so it already has a firm place, but I think the Oppenheimer movie brought it now to a new generation," says Klarnet.
Klarnet describes Einstein as "a mythical character" in popular culture. He certainly has that quality in Oppenheimer, lurking at the film's periphery, like a cameo role we eagerly await, his identity only revealed when his hat flies off and exposes that famous shock of white hair.
Though Einstein's equation E = mc2 explained the energy released in a nuclear reaction and paved the way for its sinister application, his role in the forging of an atomic bomb is perhaps overstated in the film. The poignant exchange between Oppenheimer and Einstein in the closing scene (Oppenheimer: "When I came to you with those calculations, we thought we might start a chain reaction that would destroy the entire world...") is "nonsense", says Klarnet.
Einstein, whose left-leaning views and German heritage surrounded him with suspicion, "did not have the security clearance for that", he says. In fact, the avowed pacifist distanced himself from the project and always insisted that his part in the release of atomic energy was "quite indirect".
If anyone was the instigator it was Leo Szilard, a former student of Einstein's. The letter, with Szilard's pencilled note "Original not sent!", would remain in Szilard's possession until his death in 1964. Both the German-born Einstein and the Hungarian-born Szilard were Jews who had fled to the US following the rise of Nazism and understood, better than anybody, the threat that Germany posed.