Physicists have just invented a zero-knowledge warhead inspection system using physical encryption that allows warhead scanning without revealing too much. Inspectors would send a high-energy x-ray beam through a warhead in which some of the x-ray photons would be absorbed by nuclear materials.

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Physicists have just invented a zero-knowledge warhead inspection system using physical encryption that allows warhead scanning without revealing too much. Inspectors would send a high-energy x-ray beam through a warhead in which some of the x-ray photons would be absorbed by nuclear materials.