Non-secret correlations can be used to distribute secrecy

TL;DR

This paper demonstrates that non-secret correlations can be used to distribute secrecy, highlighting a classical analog to a quantum entanglement phenomenon and strengthening the link between entanglement and secrecy.

Contribution

It introduces a classical analog to a quantum entanglement result, showing secrecy can be distributed via non-secret correlations through a private channel.

Findings

Secrecy can be distributed by sending non-secret correlations.

Strengthens the analogy between entanglement and secrecy.

Highlights the close relation between quantum entanglement and classical secrecy.

Abstract

A counter-intuitive result in entanglement theory was shown in [PRL 91 037902 (2003)], namely that entanglement can be distributed by sending a separable state through a quantum channel. In this work, following an analogy between the entanglement and secret key distillation scenarios, we derive its classical analog: secrecy can be distributed by sending non-secret correlations through a private channel. This strengthens the close relation between entanglement and secrecy.