Quantum cryptography ( qc ) is the combination of classical cryptography and quantum mechanics . the characteristics of quantum mechanics , such as no - cloning theorem and heisenberg ' s uncertainty principle , provide the perfect secrecy for quantum cryptographic communication 量子密码学是密码学与量子力学结合的产物,利用量子不可克隆定理和海森堡测不准原理等量子特性，量子密码通信理论上已经证明是绝对安全。
The second chapter of the thesis discuss emphatically the development , algorithm , remarks and present problems of dmrg . besides , we try to add odd or even sites to the rung of a two - leg coupled spin ladder , and to calculate the energy and spin gap of the class of models 第二章主要讲述了dmrg的发展、方法步骤、应用评价，目前所面临的问题，并尝试在两条耦合海森堡链的阶梯模型的“横档”上分别加入奇数、偶数今格点。
The influences of the atomic coherence and the intensity of the field on the quantum information entropy squeezing of the atomic dipoles are investigated in detail . the comparing the numerical results obtained from the uncertainty relation of heisenberg ( hur ) to those from the uncertainty relation of the quantum information entropy ( eur ) proves the triviality of hur with exact examples 具体考虑原子相干性和光场强度对原子信息熵压缩的影响，并且比较了分别从基于信息熵测不准关系和海森堡测不准关系出发得出的结果，从实例中证明信息熵压缩克服了标准偏差压缩的平庸性。
This probability cloud obeys a quantum mechanical principle called heisenberg ' s uncertainty principle , which states that there is an uncertainty in the classical position of any subatomic particle , including the electron ; so instead of describing where an electron or other particle is , the entire range of possible values is used , describing a probability distribution 这个概率云服从所谓的海森堡测不准原理的量子力学原理，原理表明任何亚原子微粒包括电子经典位置具有不确定性；因而代替描述电子或其它微粒所处位置，用全部范围里的概率值描述概率分布。
In the first chapter , we introduce briefly the idea of the ed method and its advantages and limitations , meanwhile , by using ed , we investigate the total spin of ground state ( gs ) of the finite heisenberg antiferromagnet ( haf ) cluster and the effect of side spins on the spin - spin correlation on haf chain 本文第一章在简述了ed方法的思想及其它的优点和局限的同时，更重要的是运用它对有限海森堡反铁磁团簇的基态总自旋以及准? ?维反铁磁海森堡链的自旋-自旋关联进行了研究。
M . m . nessibi and k . trimeche studied the theory of generalized wavelet transform on the underlying manifold of square integrable radial functions space on the heisen - berg group hn . they constructed an inversion formula of the radon transform on the underlying manifold by means of generalized wavelet M . m . nessibi和k . trim che研究了海森堡群h _ n上平方可积径向函数空间，在其基础流形上建立了广义小波变换理论；并利用所引进的广义小波，得到radon变换在该空间上的一个逆公式
In chapter two , we first give the condition of generalized wavelets on l2 ( x ) by using the gelfand transform , where x = r + r denotes the underlying manifold of square integrable polyradial functions on the heisenberg group hn . then , we establish the theory of generalized wavelet transform and generalized wavelet packet transform on it 在第二章中，我们利用gelfand变换刻画了海森堡群h _ n上平方可积柱径向函数空间的基础流形laguerre超群x = r _ + ~ n r上的广义小波，讨论了该超群上的广义小波变换与广义小波包变换
