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81.
三体纯态的纠缠度与量子控制隐形传送的理论分析   总被引:1,自引:0,他引:1  
对三体纯态,V.Coffman等提出了分布纠缠的概念及纠缠的度量"tangle".本文由变换算符出发,以三粒子作为量子通道对一个任意的粒子态实现控制隐形传送为例,给出纠缠度与量子控制隐形传态之间满足的关系.  相似文献   
82.
The derivation of the statistical nature of the quantum mechanical wave function is presented within the formalism of quantum mechanics and the second quantization. The statistical wave function may be derived for non relativistic bosons, non relativistic fermions, and relativistic bosons by employing the commuting field operator . For relativistic electrons a strictly anticommuting must be employed to derive the statistical wave function (spinor). The discussion at the end of the paper aims to show the physical plausibility of a statistical wave function.  相似文献   
83.
一阶变系数滞后型微分方程解的振动性积分条件与渐近性   总被引:2,自引:0,他引:2  
本文给出了一阶变系数滞后型微分方程振动解存在的积分条件,同时利用Banach不动点定理讨论了该类方程解的渐近性。  相似文献   
84.
In a Hilbert space L 2,α := L 2(?, |x|2α+1 dx), α > ? 1/2, we study the generalized Dunkl translations constructed by the Dunkl differential-difference operator. Using the generalized Dunkl translations, we define generalized modulus of smoothness in the space L 2,α . Based on the Dunkl operator we define Sobolev-type spaces and K-functionals. The main result of the paper is the proof of the equivalence theorem for a K-functional and a modulus of smoothness.  相似文献   
85.
We prove that maps into if and only if belongs to . In the case β < 1, we give another two equivalent conditions. Supported by MNZŽS Serbia, Project No. ON144010.  相似文献   
86.
Let be a conformal automorphism on the unit disk and be the composition operator on the Dirichlet space induced by . In this article we completely determine the point spectrum, spectrum, essential spectrum and essential norm of the operators and self-commutators of , which expose that the spectrum and point spectrum coincide. We also find the eigenfunctions of the operators.

  相似文献   

87.
We study those functions that can be written as a finite sum of periodic integer valued functions. On ℤ we give three different characterizations of these functions. For this we prove that the existence of a real valued periodic decomposition of a ℤ → ℤ function implies the existence of an integer valued periodic decomposition with the same periods. This result depends on the representation of the greatest common divisor of certain polynomials with integer coefficients as a linear combination of the given polynomials where the coefficients also belong to ℤ[x]. We give an example of an ℤ → {0, 1} function that has a bounded real valued periodic decomposition but does not have a bounded integer valued periodic decomposition with the same periods. It follows that the class of bounded ℤ → ℤ functions has the decomposition property as opposed to the class of bounded ℝ → ℤ functions. If the periods are pairwise commensurable or not prescribed, then we get more general results. Supported by OTKA grants T 43623 and K 61908.  相似文献   
88.
On the basis of the general framework of H-maximal monotonicity (also referred to as H-monotonicity in the literature), a generalization to Rockafellar’s theorem in the context of solving a general inclusion problem involving a set-valued maximal monotone operator using the proximal point algorithm in a Hilbert space setting is explored. As a matter of fact, this class of inclusion problems reduces to a class of variational inequalities as well as to a class of complementarity problems. This proximal point algorithm turns out to be of interest in the sense that it plays a significant role in certain computational methods of multipliers in nonlinear programming. The notion of H-maximal monotonicity generalizes the general theory of set-valued maximal monotone mappings to a new level. Furthermore, some results on general firm nonexpansiveness and resolvent mapping corresponding to H-monotonicity are also given.  相似文献   
89.
许业军  范洪义  刘秋宇 《中国物理 B》2010,19(2):20303-020303
By virtue of the completeness of Wigner operator and Weyl correspondence we construct a general equation for deriving pure state density operators. Several important examples are considered as the applications of this equation, which shows that our approach is effective and convenient for deducing these entangled state representations.  相似文献   
90.
The analysis of tautochrone problems involves the solution of integral equations. The paper shows how a reasonable assumption, based on experience with simple harmonic motion, allows one to greatly simplify such problems. Proposed solutions involve only mathematics available to students from first year calculus.  相似文献   
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