Multi-proxy quantum group signature scheme with threshold shared verification

A multi-proxy quantum group signature scheme with threshold shared verification is proposed. An original signer may authorize a proxy group as his proxy agent. Then only the cooperation of all the signers in the proxy group can generate the proxy signature on behalf of the original signer. In the scheme, any t or more of n receivers can verify the message and any t - 1 or fewer receivers cannot verify the validity of the proxy signature.

THE CANONICAL BASIS FOR THE QUANTUM GROUP OF TYPE B_2

We use the Ringel-Hall algebra approach to study the canonical basis elements for the quantum group of type B2 which are characterized in Xi [12]. However, our approach simplifies several computations there.

Cluster algebra structure on the finite dimensional representations of affine quantum group U_q(_3)

In this paper, we prove one case of conjecture given by Hemandez and Leclerc. We give a cluster algebra structuure on the Grothendieck ring of a full subcategory of the finite dimensional representations of affine quantum group Uq（A3）. As a conclusion, for every exchange relation of cluster algebra, there exists an exact sequence of the full subcategory corresponding to it.

Quantum Group Symmetry in Hofstadter Problem

We show that there is a quantum Sl_q(2) group symmetry in Hofstadter problem on square lattice.The cyclic representation of the quantum group is discussed and its application for computing the degeneracy density of the model is shown.

Tight Monomials with t-Value ≤ 9 for Quantum Group of Type D₄

All monomials with t-value ≤9 in Canonical basis of quantum group for type D4 are determined in this paper.

Tight Monomials in Quantum Group for Type <i>A</i>₅with <i>t</i>≤ 6

All tight monomials in quantum group for type A5 with t ≤ 6 are determined in this paper.

Quantum Group Signature Scheme Based on Chinese Remainder Theorem

A novel quantum group signature scheme is proposed based on Chinese Remainder Theorem (CRT), in order to improve the security of quantum signature. The generation and verification of the signature can be successfully conducted only if all the participants cooperate with each other and with the message owner's and the arbitrator's help. The quantum parallel algorithm is applied to efficiently compare the restored quantum message to the original quantum message. All the operations in signing and verifying phase can be executed in quantum circuits. It has a wide application to E-payment system, Online contract, Online notarization and etc.

A chaos-based quantum group signature scheme in quantum cryptosystem

A quantum group signature(QGS) scheme is proposed on the basis of an improved quantum chaotic encryption algorithm using the quantum one-time pad with a chaotic operation string. It involves a small-scale quantum computation network in three phases, i.e. initializing phase, signing phase and verifying phase. In the scheme, a member of the group signs the message on behalf of the group while the receiver verifies the signature's validity with the aid of the trusty group manager who plays a crucial role when a possible dispute arises. Analysis result shows that the signature can neither be forged nor disavowed by any malicious attackers.

Differential Operator Approach to■quantum Groups and Their Oscillator Representations

For a quasi-split Satake diagram,we define a modified q-Weyl algebra,and show that there is an algebra homomorphism between it and the corresponding■quantum group.In other words,we provide a differential operator approach to■quantum groups.Meanwhile,the oscillator representations of■quantum groups are obtained.The crystal basis of the irreducible subrepresentations of these oscillator representations are constructed.

Convex PBW-type Lyndon Bases and Restricted Two-parameter Quantum Group of Type F_(4)

The convex PBW-type Lyndon basis for two-parameter quantum group U_(r,s)(F_(4))is given.Assume thatrs^(-1)is a primitive l-th root of unity with l odd,then the restricted quantum group u_(r,s)(F_(4))as a quotient of U_(r,s)(F_(4))is pointed,and of a Drinfel’d double structure under a certain condition.All of Hopf isomorphisms of u_(r,s)(F_(4))are determined,and the necessary and sufficient condition for u_(r,s)(F_(4))to be a ribbon Hopf algebra is singled out by describing the left and right integrals.

Explicit Generators of the Centre of the Quantum Group

A finite generating set of the centre of any quantum group is obtained,where the generators are given by an explicit formulae.For the slightly generalised version of the quantum group which we work with,we show that this set of generators is algebraically independent,thus the centre is isomorphic to a polynomial algebra.

Differential Calculus on Compact Quantum Group U_θ(2) and its Applications

In this paper, via constructing special matrices, we will show that there exists a differential calculus on Uθ（2）, where θ is an irrational number. Then using the above results, we shall discuss the properties of infinitesimal generators of corepresentations of Uθ（2）. And in the final, we shall discuss its irreducible corepresentations and give the Peter-Weyl theorem explicitly for compact quantum group Uθ（2）.

The Compact Quantum Group Uq（2） （Ⅱ）

In this paper, we first prove that the θ-deformation Uθ（2） of U（2） constructed by Connes and Violette is our special case of the quantum group Uq（2） constructed in our previous paper. Then we will show that the set of truces on the C^＊ -algebra Uθ, θ irrational, is determined by the set of the truces on a subalgebra of Uθ.

q-Deformation of W (2 , 2) Lie Algebra Associated with Quantum Groups

The q-deformation of W（2, 2） Lie algebra is well defined based on a realization of this Lie algebra by using the famous bosonic and fermionic oscillators in physics. Furthermore, the quantum group structures on the q-deformation of W（2, 2） Lie algebra are completely determined. Finally, the 1-dimensional central extension of the q-deformed W（2, 2） Lie algebra is studied, which turns out to be coincided with the conventional W（2, 2） Lie algebra in the q → 1 limit.

Derivations and Automorphisms of the Positive Part of the Two-parameter Quantum Group U_(r,s)(B_3)

We compute the derivations of the positive part of the two-parameter quantum group Ur,s（B3） and show that the Hochschild cohomology group of degree 1 of this algebra is a three- dimensional vector space over the base field C. We also compute the groups of （Hopf） algebra automorphisms of the augmented two-parameter quantized enveloping algebra Ur,s（B3）.

R-Matrix Realization of Two-Parameter Quantum Group Ur,s(gln)

We provide a Faddeev–Reshetikhin–Takhtajan’sRTT approach to the quantum group Fun(GLr,s(n))and the quantum enveloping algebra Ur,s(gln)corresponding to the two-parameter R-matrix.We prove that the quantum determinant detr,sT is a quasi-central element in Fun(GLr,s(n))generalizing earlier results of Dipper–Donkin and Du–Parshall–Wang.The explicit formulation provides an interpretation of the deforming parameters,and the quantized algebra Ur,s(R)is identified to Ur,s(gln)as the dual algebra.We then construct n−1 quasi-central elements in Ur,s(R)which are analogs of higher Casimir elements in Uq(gln).

Quantum Double Constructions for Compact Quantum Group

For a non-degenerate pair of compact quantum groups, we first construct the quantum double as an algebraic compact quantum group in an algebraic framework. Then by adopting some completion procedure, we give the universal and reduced quantum double constructions in the correspondence C＊-algebraic settings, which generalize Drinfeld＇s quantum double construction and yield new C＊-algebraic compact quantum groups.

Categorification of Integrable Representations of Quantum Groups

We categorify the highest weight integrable representations and their tensor products of a symmetric quantum Kac–Moody algebra. As a byproduct, we obtain a geometric realization of Lusztig＇s canonical bases of these representations as well as a new positivity result. The main ingredient in the underlying geometric construction is a class of micro-local perverse sheaves on quiver varieties.

Classification on irreducible Whittaker modules over quantum group Uq(sl3,∧)

We define the Whittaker modules over the simply-connected quantum group U_(q)(sl3,∧),where A is the weight lattice of Lie algebra sl3.Then we completely classify all those simple ones.Explicitly,a simple Whittaker module over U_(q)(sl3,∧)is either a highest weight module,or determined by two parameters z∈C andγ∈C^(*)(up to a Hopf automorphism).

Characterization of compact quantum group

Given a C^＊-algebra A and a comultiplication Ф on A, we show that the pair （A, Ф） is a compact quantum group if and only if the associated multiplier Hopf ^＊-algebra （A, ФA） is a compact Hopf ^＊-algebra.