Quantum computers pose a big threat to the security of modern communications, deciphering cryptographic codes that would take regular computers forever to crack. But drawing on the properties of quantum behaviour could also provide a route to truly secure cryptography.
Defence, finance, social networking – communications everywhere rely on cryptographic security. Cryptography involves jumbling up messages according to a code, or key, that has too many combinations for even very powerful computers to try out.
But quantum computers have an advantage. Unlike regular computers, which process information in ‘bits’ of definite ones and zeros, quantum computers process information in ‘qubits’, the states of which remain uncertain until the final calculation.
The result is that a quantum computer can effectively try out many different keys in parallel. Cryptography that would be impenetrable to regular computers could take a quantum computer mere seconds to crack. […]
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