Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:1411.0013 · Results in Physics

Insecurity of a relativistic quantum commitment scheme

Guang Ping He

Published May 27, 2023• 0 citations
arXivHTMLPDF

Abstract

We propose a cheating strategy to a relativistic quantum commitment scheme (Nadeem, 2014) which was claimed to be unconditionally secure. It is shown that the sender Alice can cheat successfully with probability 100%, thus disproving the security claim.
DOI
10.1016/j.rinp.2023.106568

Related papers

Comment on "Unconditionally secure commitment in position-based quantum cryptography"

Guang Ping He

We show that a recently proposed relativistic commitment scheme [Sci. Rep. 4, 6774 (2014). arXiv:1406.6679] is insecure against the cheating of the committer.

•Oct 31, 2014•0 citations

Is Quantum Bit Commitment Really Possible?

Hoi‐Kwong Lo, H. F. Chau

We show that all proposed quantum bit commitment schemes are insecure because the sender, Alice, can almost always cheat successfully by using an Einstein-Podolsky-Rosen--type of attack and delaying her measurement until she opens her commitment.

arXiv:quant-ph/9603004•Physical Review Letters•Apr 28, 1997•603 citations

Unconditionally Secure Quantum Bit Commitment is Simply Possible

Arindam Mitra

It has been claimed that unconditionally secure quantum bit commitment is impossible. This claim has been widely accepted and is commonly referred to as the no-go theorem. The no-go theorem implicitly raises the question of whether quantum mechanics can be collectively verified with unconditional security against cheating. We demonstrate that by following an alternative quantum encoding scheme, unconditionally secure quantum bit commitment can, in fact, be achieved.

arXiv:physics/0007089•Jul 28, 2000•1 citation

Why Quantum Bit Commitment And Ideal Quantum Coin Tossing Are Impossible

Hoi-kwong Lo, H. F. Chau

There had been well known claims of unconditionally secure quantum protocols for bit commitment. However, we, and independently Mayers, showed that all proposed quantum bit commitment schemes are, in principle, insecure because the sender, Alice, can almost always cheat successfully by using an Einstein-Podolsky-Rosen (EPR) type of attack and delaying her measurements. One might wonder if secure quantum bit commitment protocols exist at all. We answer this question by showing that the same type of attack by Alice will, in principle, break any bit commitment scheme. The cheating strategy generally requires a quantum computer. We emphasize the generality of this ``no-go theorem'': Unconditionally secure bit commitment schemes based on quantum mechanics---fully quantum, classical or quantum but with measurements---are all ruled out by this result. Since bit commitment is a useful primitive for building up more sophisticated protocols such as zero-knowledge proofs, our results cast very serious doubt on the security of quantum cryptography in the so-called ``post-cold-war'' applications. We also show that ideal quantum coin tossing is impossible because of the EPR attack. This no-go theorem for ideal quantum coin tossing may help to shed some lights on the possibility of non-ideal protocols.

•Jan 1, 1996•172 citations

Why quantum bit commitment and ideal quantum coin tossing are impossible

Hoi‐Kwong Lo, H. F. Chau

There had been well known claims of ``provably unbreakable'' quantum protocols for bit commitment and coin tossing. However, we, and independently Mayers, showed that all proposed quantum bit commitment (and therefore coin tossing) schemes are, in principle, insecure because the sender, Alice, can always cheat successfully by using an EPR-type of attack and delaying her measurements. One might wonder if secure quantum bit commitment and coin tossing protocols exist at all. Here we prove that an EPR-type of attack by Alice will, in principle, break {\em any} realistic quantum bit commitment and {\em ideal} coin tossing scheme. Therefore, provided that Alice has a quantum computer and is capable of storing quantum signals for an arbitrary length of time, all those schemes are insecure. Since bit commitment and coin tossing are useful primitives for building up more sophisticated protocols such as zero-knowledge proofs, our results cast very serious doubt on the security of quantum cryptography in the so-called ``post-cold-war'' applications.

arXiv:quant-ph/9605026•May 16, 1996•7 citations

Cheat Sensitive Quantum Bit Commitment

Lucién Hardy, Adrian Kent

We define cheat sensitive cryptographic protocols between mistrustful parties as protocols which guarantee that, if either cheats, the other has some nonzero probability of detecting the cheating. We describe an unconditionally secure cheat sensitive nonrelativistic bit commitment protocol which uses quantum information to implement a task which is classically impossible; we also describe a simple relativistic protocol.

arXiv:quant-ph/9911043•Physical Review Letters•Apr 16, 2004•98 citations
There had been well known claims of unconditionally secure quantum protocols for bit commitment. However, we, and independently Mayers, showed that all proposed quantum bit commitment schemes are, in principle, insecure because the sender, Alice, can almost always cheat successfully by using an Einstein-Podolsky-Rosen (EPR) type of attack and delaying her measurements. One might wonder if secure quantum bit commitment protocols exist at all. We answer this question by showing that the same type of attack by Alice will, in principle, break any bit commitment scheme. The cheating strategy generally requires a quantum computer. We emphasize the generality of this ``no-go theorem'': Unconditionally secure bit commitment schemes based on quantum mechanics---fully quantum, classical or quantum but with measurements---are all ruled out by this result. Since bit commitment is a useful primitive for building up more sophisticated protocols such as zero-knowledge proofs, our results cast very serious doubt on the security of quantum cryptography in the so-called ``post-cold-war'' applications. We also show that ideal quantum coin tossing is impossible because of the EPR attack. This no-go theorem for ideal quantum coin tossing may help to shed some lights on the possibility of non-ideal protocols.
There had been well known claims of ``provably unbreakable'' quantum protocols for bit commitment and coin tossing. However, we, and independently Mayers, showed that all proposed quantum bit commitment (and therefore coin tossing) schemes are, in principle, insecure because the sender, Alice, can always cheat successfully by using an EPR-type of attack and delaying her measurements. One might wonder if secure quantum bit commitment and coin tossing protocols exist at all. Here we prove that an EPR-type of attack by Alice will, in principle, break {\em any} realistic quantum bit commitment and {\em ideal} coin tossing scheme. Therefore, provided that Alice has a quantum computer and is capable of storing quantum signals for an arbitrary length of time, all those schemes are insecure. Since bit commitment and coin tossing are useful primitives for building up more sophisticated protocols such as zero-knowledge proofs, our results cast very serious doubt on the security of quantum cryptography in the so-called ``post-cold-war'' applications.