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131.
A connection between Romanovski polynomials and those polynomials that solve the one-dimensional Schrödinger equation with the trigonometric Rosen-Morse and hyperbolic Scarf potential is established. The map is constructed by reworking the Rodrigues formula in an elementary and natural way. The generating function is summed in closed form from which recursion relations and addition theorems follow. Relations to some classical polynomials are also given.  相似文献   
132.
We show that the difference between the Schrödinger uncertainty relations (UR) and the Heisenberg UR is fundamental. We propose a modified version of stochastic mechanics that allows clearly demonstrating that the contributions from the anticommutator and the commutator to the Schrödinger UR are equally important. A classification of quantum states minimizing the Schrödinger UR at an arbitrary instant is proposed. We show that the correlation of the coordinate and momentum fluctuations in such correlated-coherent states (CCS) is largely determined by the contributions from not only the commutator but also the anticommutator of the corresponding operators. We demonstrate that the character of this correlation changes qualitatively in time from the antiphase correlation typical for the Heisenberg UR to the inphase correlation for which the contribution from the anticommutator is decisive. We comparatively analyze properties of a free microparticle and a quantum oscillator in CCS and show that the CCS correspond to traveling-standing de Broglie waves in both models.  相似文献   
133.
A forward dispersion calculation is implemented for the spin polarizabilities γ1,,γ4 of the proton and the neutron. These polarizabilities are related to the spin structure of the nucleon at low energies and are structure-constants of the Compton scattering amplitude at . In the absence of a direct experimental measurement of these quantities, a dispersion calculation serves the purpose of constraining the model building, and of comparing with recent calculations in heavy baryon chiral perturbation theory.  相似文献   
134.
We study here some linear recurrence relations in the algebra of square matrices. With the aid of the Cayley–Hamilton Theorem, we derive some explicit formulas for An (nr) and etA for every r×r matrix A, in terms of the coefficients of its characteristic polynomial and matrices Aj, where 0jr−1.  相似文献   
135.
This study examines a linear variation of the specific heat CP with the frequency shifts 1/ν(∂ν/∂T) for the Brillouin frequencies of the L-mode [010], [001] and [100] in the ferroelectric phase of NaNO2 according to our spectroscopically modified Pippard relation. We obtain this linear relationship for those modes studied and calculate dTC/dP in the ferroelectric phase of NaNO2. Our calculated values of dTC/dP for the [001] and [100] modes are in good agreement with the values given in the literature.  相似文献   
136.
137.
多晶金属弹粘塑性的取向元模型   总被引:2,自引:0,他引:2  
基于“三维组集式本构模型”[1~3],运用功共轭原理和场平均方法,发展了一种“取向元”概念——多晶聚集体内具有相同取向的滑移系集的一个体积平均意义上的代表性元素;由一维的率(粘性)敏感“取向元”,通过在取向空间里的积分,获得了三维的弹粘塑性本构方程式,并模拟了蠕变和松弛现象.与以往的粘塑性模型相比,本文模型不仅能同时考虑多晶金属材料的率相关性和路径相关性,而且由于引入了物理机制,因而具有较强的预测能力.数值算例也展示了该模型的合理性  相似文献   
138.
We present a new approach to study the convergence of Newton's method in Banach spaces, which relax the conditions appearing in the usual studies. The approach is based on the bound required for the second derivative of the operator involved. An application to a nonlinear integral equation is presented.  相似文献   
139.
利用母函数的方法,研究了第一类和第二类切比雪夫多项式,分别得到二类切比雪夫多项式积和式的几个有趣的恒等式.并利用切比雪夫多项式和Fibonacci数、Lucas数的内在联系,得到了Fibonacci数和Lucas数之间的一些有趣的恒等式.  相似文献   
140.
We consider a model of particle motion in the field of an electromagnetic monopole (in the Coulomb-Dirac field) perturbed by homogeneous and inhomogeneous electric fields. After quantum averaging, we obtain an integrable system whose Hamiltonian can be expressed in terms of the generators of an algebra with polynomial commutation relations. We construct the irreducible representations of this algebra and its hypergeometric coherent states. We use these states to represent the eigenfunctions of the original problem in terms of the solutions of the model ordinary differential equation. We also present the asymptotic approximations of the eigenvalues in the leading term of the perturbation theory, where the degeneration of the spectrum is removed completely.Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 142, No. 1, pp. 127–147, January, 2005.  相似文献   
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