# Strong no-go theorem for Gaussian quantum bit commitment

@article{Magnin2010StrongNT, title={Strong no-go theorem for Gaussian quantum bit commitment}, author={Lo{\"i}ck Magnin and Fr{\'e}d{\'e}ric Magniez and Anthony Leverrier and Nicolas J. Cerf}, journal={Physical Review A}, year={2010}, volume={81}, pages={010302} }

Unconditionally secure bit commitment is forbidden by quantum mechanics. We extend this no-go theorem to continuous-variable protocols where both players are restricted to use Gaussian states and operations, which is a reasonable assumption in current-state optical implementations. Our Gaussian no-go theorem also provides a natural counter-example to a conjecture that quantum mechanics can be rederived from the assumption that key distribution is allowed while bit commitment is forbidden in…

## 27 Citations

Quantum bit commitment under Gaussian constraints

- Computer Science
- 2012

A quantum bit commitment protocol is introduced and it is proved that it is asymptotically secure if cheating is restricted to Gaussian operations.

Quantum key distribution based on orthogonal states allows secure quantum bit commitment

- Computer Science
- 2011

A QBC protocol is built in which the density matrices of the quantum states encoding the commitment do not satisfy a crucial condition on which the no-go proofs of QBC are based, so that theNo- go proofs could be evaded.

Unconditionally secure quantum bit commitment based on the uncertainty principle

- Computer ScienceProceedings of the Royal Society A
- 2019

A simple QBC protocol is proposed which manages to evade the no-go proofs and is found that in high-dimensional systems, there exist some states which can display a chaos effect in quantum steering.

Simplified quantum bit commitment using single photon nonlocality

- PhysicsQuantum Inf. Process.
- 2014

We simplified our previously proposed quantum bit commitment (QBC) protocol based on the Mach–Zehnder interferometer, by replacing symmetric beam splitters with asymmetric ones. It eliminates the…

Quantum bit commitment is weaker than quantum bit seals

- Computer Science
- 2014

It is shown that secure QBC can be built upon secure QBS, but not vice versa, which seems that QBC is strictly weaker than QBS in security requirement.

Practical Quantum Bit Commitment Protocol Based on Quantum Oblivious Transfer

- Computer Science, MathematicsApplied Sciences
- 2018

This paper proposes three practical quantum cryptographic protocols and gives a definition of physical security for QBC protocols and proves that the practical QBC protocol is physically secure and can be implemented in the real world.

Semi-Counterfactual Quantum Bit Commitment Protocol

- Computer ScienceScientific Reports
- 2020

A semi-counterfactual quantum bit commitment (SCQBC) protocol is presented here for the first time, which makes use of counterfactual property, and a general bit commitment framework can be extracted from the SCQBC scheme, which opens up a new class of cryptographic protocols inCounterfactual cryptography.

Oblivious transfer based on quantum state computational distinguishability

- Computer Science, MathematicsArXiv
- 2014

This paper presents a quantum computationally secure protocol for oblivious transfer between two parties, under the assumption of quantum hardness of state distinguishability, and it is feasible, in the sense that it is implementable in polynomial time.

Theoretical study of continuous-variable quantum key distribution

- Computer Science, Mathematics
- 2009

This thesis develops an optimal reconciliation algorithm for the initial protocol, then introduces a new protocol for which the reconciliation problem is automatically taken care of thanks to a discrete modulation, and introduces and study a class of symmetries in phase space, which is particularly relevant for continuous-variable QKD.

Distributing Secret Keys with Quantum Continuous Variables: Principle, Security and Implementations

- Computer ScienceEntropy
- 2015

The principle of continuous-variable quantum key distribution is described, focusing in particular on protocols based on coherent states, and the security of these protocols is discussed and the state-of-the-art in experimental implementations are reported, including the issue of side-channel attacks.

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