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71.
Michał Dobrski 《Central European Journal of Physics》2007,5(3):313-323
In this paper we introduce a method for finding a time independent Hamiltonian of a given Hamiltonian dynamical system by
canonoid transformation of canonical momenta. We find a condition that the system should satisfy to have an equivalent time
independent formulation. We study the example of a damped harmonic oscillator and give the new time independent Hamiltonian
for it, which has the property of tending to the standard Hamiltonian of the harmonic oscillator as damping goes to zero.
相似文献
72.
The purpose of this paper is to generalize Yalçin's result [Trans. Amer. Math. Soc. 352 , 2689–2700 (2000)] from tori to solvmanifolds. As a result, we prove that if (?p)r acts freely on a solvmanifold M of dimension n, then r ≤ n (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
73.
74.
该文证明了随机元序列的一个一般的几乎处处中心极限定理, 并把这一结论应用于随机变量序列的函数. 相似文献
75.
Under the conditions of a strong Coulomb repulsion between electrons at a lattice site, we now study the equations for the
self-energy part of the electron Green’s function, which we previously obtained using the generating functional method. These
equations have a form close to that corresponding to the self-consistent Born approximation in the weak-coupling theory. In
these equations, we omit the dependence of the self-energy on the momentum, which corresponds to the infinite-dimensional
space limit. We then numerically solve the integral equations, where all the variables depend only on the frequency, and obtain
results consistent with the dynamical mean field theory. In particular, we show that as the Coulomb repulsion increases, the
three-peak structure of the quasiparticle spectrum changes into a two-peak structure and the metal–insulator phase transition
occurs. The proposed method can be used to study other models of the theory of strongly correlated systems.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 154, No. 1, pp. 63–76, January, 2008. 相似文献
76.
Abstract: We consider an approximation problem related to strongly irreducible operators, that is, does the direct sum of a strongly irreducible operator in B∞(Ω) and certain operator have a small compact perturbation which is a strongly irreducible operator in B∞(Ω)? In this paper, we prove that the direct sum of any strongly irreducible operator in B∞(Ω) and certain biquasitriangular operator have small compact perturbations which are strongly irreducible operators in B∞(Ω). 相似文献
77.
高正晖 《数学的实践与认识》2008,38(11):178-183
研究了一类含连续分布滞量和阻尼项的非线性双曲型偏微分方程组运用黎卡提变换获得了该方程组在两类边值条件下解振动的充分条件. 相似文献
78.
The paper is devoted to a careful analysis of the shape-preserving properties of the strongly continuous semigroup generated
by a particular second-order differential operator, with particular emphasis on the preservation of higher order convexity
and Lipschitz classes. In addition, the asymptotic behaviour of the semigroup is investigated as well. The operator considered
is of interest, since it is a unidimensional Black-Scholes operator so that our results provide qualitative information on
the solutions of classical problems in option pricing theory in Mathematical Finance.
The paper is dedicated to Professor Luigi Albano on the occasion of his 70th birthday. 相似文献
79.
In this paper, a kind of optimization problems with nonlinear inequality constraints is discussed. Combined the ideas of norm-relaxed SQP method and strongly sub-feasible direction method as well as a pivoting operation, a new fast algorithm with arbitrary initial point for the discussed problem is presented. At each iteration of the algorithm, an improved direction is obtained by solving only one direction finding subproblem which possesses small scale and always has an optimal solution, and to avoid the Maratos effect, another correction direction is yielded by a simple explicit formula. Since the line search technique can automatically combine the initialization and optimization processes, after finite iterations, the iteration points always get into the feasible set. The proposed algorithm is proved to be globally convergent and superlinearly convergent under mild conditions without the strict complementarity. Finally, some numerical tests are reported. 相似文献
80.
刻划了赋序列范数的矢值B anach序列空间ss(E)的强暴露性和暴露性,给出了它们的判据. 相似文献