Unconditionally secure quantum bit commitment based on the uncertainty principle

TL;DR

This paper proposes a new quantum bit commitment protocol that circumvents previous impossibility proofs by leveraging high-dimensional quantum states and the uncertainty principle, enabling unconditionally secure commitments.

Contribution

It introduces a QBC protocol that evades no-go proofs by exploiting chaos effects in high-dimensional systems and the uncertainty principle.

Findings

The protocol can achieve unconditional security against known attacks.

High-dimensional states introduce a chaos effect that prevents effective cheating.

The approach challenges previous assumptions about the impossibility of secure QBC.

Abstract

Unconditionally secure quantum bit commitment (QBC) was considered impossible. But the no-go proofs are based on the Hughston-Jozsa-Wootters (HJW) theorem (a.k.a. the Uhlmann theorem). Recently it was found that in high-dimensional systems, there exist some states which can display a chaos effect in quantum steering, so that the attack strategy based on the HJW theorem has to require the capability of discriminating quantum states with very subtle difference, to the extent that is not allowed by the uncertainty principle. With the help of this finding, here we propose a simple QBC protocol which manages to evade the no-go proofs.