Zero-knowledge convincing protocol on quantum bit is impossible

Consider two parties: Alice and Bob and suppose that Bob is given a qubit system in a quantum state ϕ, unknown to him. Alice knows ϕ and she is supposed to convince Bob that she knows ϕ sending some test message. Is it possible for her to convince Bob providing him "zero knowledge" i. e. no information about ϕ he has? We prove that there is no "zero knowledge" protocol of that kind. In fact it turns out that basing on Alice message, Bob (or third party - Eve - who can intercept the message) can synthetize a copy of the unknown qubit state ϕ with nonzero probability. This "no-go" result puts general constrains on information processing where information about quantum state is involved.

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An access control model for the Internet of Things based on zero-knowledge token and blockchain

EURASIP Journal on Wireless Communications and Networking ◽

10.1186/s13638-021-01986-4 ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

Lihua Song ◽

Xinran Ju ◽

Zongke Zhu ◽

Mengchen Li

Keyword(s):

Internet Of Things ◽

Access Control ◽

Single Point ◽

Control Model ◽

Third Party ◽

Security Level ◽

Zero Knowledge ◽

Access Control Model ◽

Test Analysis ◽

Zero Knowledge Proof

AbstractInformation security has become a hot topic in Internet of Things (IoT), and traditional centralized access control models are faced with threats such as single point failure, internal attack, and central leak. In this paper, we propose a model to improve the access control security of the IoT, which is based on zero-knowledge proof and smart contract technology in the blockchain. Firstly, we deploy attribute information of access control in the blockchain, which relieves the pressure and credibility problem brought by the third-party information concentration. Secondly, encrypted access control token is used to gain the access permission of the resources, which makes the user's identity invisible and effectively avoids attribute ownership exposure problem. Besides, the use of smart contracts solves the problem of low computing efficiency of IoT devices and the waste of blockchain computing power resources. Finally, a prototype of IoT access control system based on blockchain and zero-knowledge proof technology is implemented. The test analysis results show that the model achieves effective attribute privacy protection, compared with the Attribute-Based Access Control model of the same security level, the access efficiency increases linearly with the increase of access scale.

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Quantum Bit Commitment and the Reality of the Quantum State

Foundations of Physics ◽

10.1007/s10701-017-0130-3 ◽

2018 ◽

Vol 48 (1) ◽

pp. 92-109 ◽

Cited By ~ 2

Author(s):

R. Srikanth

Keyword(s):

Quantum State ◽

Quantum Bit ◽

Bit Commitment

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On the classical character of control fields in quantum information processing

Quantum Information and Computation ◽

10.26421/qic2.1-1 ◽

2002 ◽

Vol 2 (1) ◽

pp. 1-13

Author(s):

S.J. van Enk ◽

H.J. Kimble

Keyword(s):

Quantum Computing ◽

Information Processing ◽

Quantum Information ◽

Laser Beam ◽

Quantum State ◽

Quantum Communication ◽

Quantum Information Processing ◽

Laser Fields ◽

Undesirable Property

Control fields in quantum information processing are almost by definition assumed to be classical. In reality, however, when such a field is used to manipulate the quantum state of qubits, the qubits always become slightly entangled with the field. For quantum information processing this is an undesirable property, as it precludes perfect quantum computing and quantum communication. Here we consider the interaction of atomic qubits with laser fields and quantify atom-field entanglement in various cases of interest. We find that the entanglement decreases with the average number of photons \bar{n} in a laser beam as $E\propto\log_2 \bar{n}/\bar{n}$ for $\bar{n}\rightarrow\infty$.

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EFFICIENT ALGORITHM FOR INITIALIZING AMPLITUDE DISTRIBUTION OF A QUANTUM REGISTER

Modern Physics Letters B ◽

10.1142/s0217984901003093 ◽

2001 ◽

Vol 15 (27) ◽

pp. 1259-1264 ◽

Cited By ~ 1

Author(s):

M. ANDRECUT ◽

M. K. ALI

Keyword(s):

Information Processing ◽

Quantum Information ◽

Quantum Computation ◽

Quantum State ◽

Efficient Algorithm ◽

Quantum Information Processing ◽

Amplitude Distribution ◽

Quantum Register

The preparation of a quantum register in an arbitrary superposed quantum state is an important operation for quantum computation and quantum information processing. Here, we present an efficient algorithm which requires a polynomial number of elementary operations for initializing the amplitude distribution of a quantum register.

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An efficient scheme for five-party quantum state sharing of an arbitrary m-qubit state using multiqubit cluster states

Quantum Information Processing ◽

10.1007/s11128-010-0211-0 ◽

2010 ◽

Vol 10 (4) ◽

pp. 463-473 ◽

Cited By ~ 43

Author(s):

Kui Hou ◽

Guo-Hong Liu ◽

Xue-Yong Zhang ◽

Shou-Qi Sheng

Keyword(s):

Quantum State ◽

Qubit State ◽

Quantum State Sharing ◽

Cluster States ◽

Efficient Scheme

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Proposal for dimensionality testing in QPQ

Quantum Information and Computation ◽

10.26421/qic18.13-14-4 ◽

2018 ◽

Vol 18 (13&14) ◽

pp. 1125-1142

Author(s):

Arpita Maitra ◽

Bibhas Adhikari ◽

Satyabrata Adhikari

Keyword(s):

Information Processing ◽

Quantum Information ◽

Quantum System ◽

Quantum State ◽

Quantum Information Processing ◽

Quantum States ◽

Quantum Private Query ◽

Unfair Advantage ◽

Security Proofs

Recently, dimensionality testing of a quantum state has received extensive attention (Ac{\'i}n et al. Phys. Rev. Letts. 2006, Scarani et al. Phys. Rev. Letts. 2006). Security proofs of existing quantum information processing protocols rely on the assumption about the dimension of quantum states in which logical bits are encoded. However, removing such assumption may cause security loophole. In the present paper, we show that this is indeed the case. We choose two players' quantum private query protocol by Yang et al. (Quant. Inf. Process. 2014) as an example and show how one player can gain an unfair advantage by changing the dimension of subsystem of a shared quantum system. To resist such attack we propose dimensionality testing in a different way. Our proposal is based on CHSH like game. As we exploit CHSH like game, it can be used to test if the states are product states for which the protocol becomes completely vulnerable.

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Quantum-inspired learning vector quantizers for prototype-based classification

Neural Computing and Applications ◽

10.1007/s00521-020-05517-y ◽

2020 ◽

Author(s):

Thomas Villmann ◽

Alexander Engelsberger ◽

Jensun Ravichandran ◽

Andrea Villmann ◽

Marika Kaden

Keyword(s):

State Space ◽

Quantum State ◽

Inner Product ◽

Mathematical Framework ◽

Feature Mapping ◽

Quantum Bit ◽

Vector Quantizers ◽

New Ideas ◽

Learning Scenarios ◽

Bit Vector

AbstractPrototype-based models like the Generalized Learning Vector Quantization (GLVQ) belong to the class of interpretable classifiers. Moreover, quantum-inspired methods get more and more into focus in machine learning due to its potential efficient computing. Further, its interesting mathematical perspectives offer new ideas for alternative learning scenarios. This paper proposes a quantum computing-inspired variant of the prototype-based GLVQ for classification learning. We start considering kernelized GLVQ with real- and complex-valued kernels and their respective feature mapping. Thereafter, we explain how quantum space ideas could be integrated into a GLVQ using quantum bit vector space in the quantum state space $${\mathcal {H}}^{n}$$ H n and show the relations to kernelized GLVQ. In particular, we explain the related feature mapping of data into the quantum state space $${\mathcal {H}}^{n}$$ H n . A key feature for this approach is that $${\mathcal {H}}^{n}$$ H n is an Hilbert space with particular inner product properties, which finally restrict the prototype adaptations to be unitary transformations. The resulting approach is denoted as Qu-GLVQ. We provide the mathematical framework and give exemplary numerical results.

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