- Albert Einstein plays a significant role in the $4
- In reality, Einstein and J. Robert Oppenheimer knew each other but weren't friends until much later.
For someone who wasn't involved in the race to develop the first atomic bomb, $4 plays a surprisingly significant role in the Christopher Nolan film "Oppenheimer."
The movie focuses on $4, who led the assembly and testing of the first-ever atomic bomb at Los Alamos in New Mexico.
In several scenes, the physicist, who is becoming the "father of the atom bomb," goes to Einstein for advice during and after the secret initiative, code-named the $4.
But in reality "Oppenheimer and Einstein were not friends," $4 historian Alex Wellerstein told Insider. "They knew each other. They worked in the same place after the war. But Oppenheimer saw Einstein as kind of the old guard."
Einstein once $4 that he didn't believe in $4, which would become Oppenheimer's field of study. The younger scientist later called Einstein "completely $4."
It wasn't until the last decade of $4, after the bombs had already dropped, the war had ended, and both physicists were at Princeton, that the two came to be "close colleagues and something of friends," Oppenheimer $4 in 1965.
"I saw the relationship between them as very much one of the master who'd been supplanted and whose work had been taken over by the younger," Nolan told the $4.
The movie captures some of the real-life tension and, later, the camaraderie between the two influential physicists. But some parts of it are fiction.
Einstein would not have helped with top-secret calculations
In the film, as in history, a $4 calculates that the atomic bomb they're building could set off an unending chain of reactions that ignites the entire atmosphere.
Facing the possibility that his experiment will $4, Oppenheimer rushes to Einstein to double-check the numbers. That's pure fiction.
"He didn't go to Einstein and ask him to check $4. That did not happen. Einstein wouldn't have been any good for that anyway," Wellerstein said. "It's the wrong kind of science."
Even if Einstein had been the man for that job, it's unlikely that Oppenheimer would have gone to him with such confidential calculations.
In reality, Oppenheimer consulted Arthur Compton, who was directing the University of Chicago efforts of the Manhattan Project.
"I shifted that to Einstein," Nolan told the Times. "Einstein is the personality people know in the audience."
Einstein and Oppenheimer disagreed on a key issue: the government
Einstein wasn't invited to join the Manhattan Project, partially because of his socialist leanings, but it's possible he wouldn't have accepted such an invitation anyway.
The scientist was a staunch pacifist. Out of fear the $4, Einstein wrote the letter that convinced President Franklin D. Roosevelt to launch an atomic-bomb program.
He later regretted it, saying: "Had I known that the $4 in developing an atomic bomb, I would have done nothing."
Einstein was a $4, having fled the Gestapo raids and Hitler's rise. His distrust of the government doesn't feature prominently in the movie. Instead, there is a glimpse of it in his eyes as he passes Senator Lewis Strauss in one of the film's most critical scenes, beside the pond at Princeton.
In the movie, Strauss is convinced that Oppenheimer said something to turn Einstein against him. But Einstein turned against politicians long before that.
"The trouble with Oppenheimer is that he loves a woman who doesn't love him — the United States government," Einstein once said, according to the book "American Prometheus," which the movie is based on.
That's an "$4," Wellerstein said.
Einstein did encourage Oppenheimer to turn his back on the US
After all his work, and after the war was over, Oppenheimer's life came under a bizarre national security investigation, which is the subject of the movie's third act.
Einstein did, in fact, tell Oppenheimer to give up his security clearance and walk away from government work. That scene in the movie is based on true events.
"There's a fundamental difference between the two of them that I think is exposed in this. Einstein did not think that Oppenheimer owed the government anything or the country anything like that," Wellerstein said.
Oppenheimer, however, couldn't let it go.
Einstein the outsider, Oppenheimer the disgraced insider
After the government decided to revoke his security clearance, Oppenheimer stopped working on nuclear issues altogether. His career virtually ended.
"Even though he knew a lot of things and had a lot of opinions, he basically felt like, if you didn't have a security clearance, you were not capable of being an important person," Wellerstein said.
"Somebody like Einstein would think that's nonsense," he added, calling the $4 "a perpetual outsider."
Wellerstein concluded, conversely, that "Oppenheimer starts as kind of an outsider, becomes this really key insider, and then gets kicked out and never can recover from that."