Learn How Richard Feynman Cracked the Safes with Atomic Secrets at Los Alamos

The story has become part of physics lore: A young Richard Feynman, future Nobel winner, was bored with life in the remote New Mexico desert while working on the atomic bomb during World War II, so he amused himself by learning to pick the combination locks in the supposedly secure filing cabinets containing America’s nuclear secrets. As Feynman would later write in his essay, “Safecracker Meets Safecracker”:

To demonstrate that the locks meant nothing, whenever I wanted somebody’s report and they weren’t around, I’d just go in their office, open the filing cabinet, and take it out. When I was finished I would give it back to the guy: “Thanks for your report.”

“Where’d you get it?”

“Out of your filing cabinet.”

“But I locked it!”

“I know you locked it. The locks are no good.”

So the officials at Los Alamos installed cabinets with better locks. But Feynman studied the new ones systematically, and eventually, given a little time, he could open any lock at will. As a joke, he left a note in one cabinet that said, “I borrowed document no. LA4312–Feynman the safecracker.”

I opened the safes which contained all the secrets to the atomic bomb: the schedules for the production of the plutonium, the purification procedures, how much material is needed, how the bomb works, how the neutrons are generated, what the design is, the dimensions–the entire information that was known at Los Alamos: the whole schmeer!

To learn a bit about how Feynman did it, watch this fascinating little video by journalist Brady Haran of the YouTube-funded Numberphile. Haran interviews Roger Bowley, emeritus professor of physics at the University of Nottingham, who explains several of the ingenious methods used by Feynman to solve the problem of cracking a lock with (supposedly) a million possible combinations. And to learn more about Feynman’s adventure as a safecracker, be sure to read “Safecracker Meets Safecracker,” which is included in his book Surely You’re Joking, Mr. Feynman! and can be read on PDF by clicking here.

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Related Content:

Free: Richard Feynman’s Physics Course from Cornell (1964)

The Richard Feynman Trilogy: The Physicist Captured in Three Films

Richard Feynman’s Ode to a Flower: A Short Animation

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