From 2000BC, cryptography used substitution ciphers and relied on a key exchange. With Public Key Cryptography, Mathematics enabled exchange of a secret message without sharing a secret key. Now, through Physics, cryptography is literally awaiting a quantum leap: Can you transmit a key in the open without risk of eavesdropping?

Prof. Kurt Langfeld explains concepts from Free Mason ciphers through to RSA, before explaining and illustrating Quantum Cryptography.

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