An Elementary Proof of Private Random Number Generation from Bell Inequalities

TL;DR

This paper presents a simplified, elementary proof that any bipartite Bell violation can be used to generate private random numbers, advancing the understanding of device-independent quantum cryptography.

Contribution

It introduces a short, self-contained proof leveraging the mirror adversary concept, simplifying previous complex security proofs in the field.

Findings

Any bipartite Bell violation can generate private randomness

The proof is elementary and self-contained

Simplifies existing security proofs in device-independent quantum cryptography

Abstract

The field of device-independent quantum cryptography has seen enormous success in the past several years, including security proofs for key distribution and random number generation that account for arbitrary imperfections in the devices used. Full security proofs in the field so far are long and technically deep. In this paper we show that the concept of the mirror adversary can be used to simplify device-independent proofs. We give a short proof that any bipartite Bell violation can be used to generate private random numbers. The proof is based on elementary techniques and is self-contained.