Stephen Wiesner

research physicist

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July 22, 2026

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Stephen Wiesner was a research physicist who proposed an idea for creating unforgeable money using quantum mechanics. He envisioned a "quantum banknote" that would contain quantum systems. Any attempt to measure or duplicate these systems would alter their original state, thus revealing any counterfeiting attempt.12

While Wiesner's paper on this concept was not initially published, his idea inspired Charles Bennett and Gilles Brassard. They developed the first quantum cryptography scheme, known as BB84, based on Wiesner's concept. This scheme uses polarized photons to securely transmit information, with any eavesdropping attempt altering the data and alerting the intended recipients.12

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Charles H. Bennett
…became friends with fellow student Stephen Wiesner. They kept in touch while Wiesner went to graduate school at Columbia, and Wiesner told Bennett about his idea for using quantum mechanics to create money that could not be counterfeited. Such a “quantum” banknote would contain 20 two-state quantum systems in which…
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…became friends with fellow student Stephen Wiesner. They kept in touch while Wiesner went to graduate school at Columbia, and Wiesner told Bennett about his idea for using quantum mechanics to create money that could not be counterfeited. Such a “quantum” banknote would contain 20 two-state quantum systems in which…
Read More