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Leó Szilárd had just read H.G. Wells' novel 'The World Set Free,' which describe
1933 Event

September 12

Szilard Envisions Chain Reaction: Nuclear Age Dawns

Leó Szilárd had just read H.G. Wells' novel 'The World Set Free,' which described atomic bombs destroying cities, when he stepped off the curb at Southampton Row. The traffic light turned red. He waited. And standing there, he worked out that if a neutron could split an atom and release two neutrons, those two could split two more atoms, releasing four — and so on, indefinitely. He filed a patent on the chain reaction in 1934 and assigned it to the British Admiralty to keep it secret. He'd just invented the theoretical basis for both nuclear power and the atomic bomb, at a traffic light.

September 12, 1933

93 years ago

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