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141.
H一射影循环Kaehler流形 总被引:2,自引:0,他引:2
李中林 《浙江大学学报(理学版)》1994,21(1):16-19
本文研究H一射影循环Kaehler流形的性质,导出了该流形曲率张量的代数结构,从而深化了这类流形的已有结果。 相似文献
142.
The symmetry orbital-symmetry orbital tensor method is applied to the evaluation of molecular integrals (one-electron and two-electron integrals) and the symmetry-orbital-tensor and self-consistent-field (SOT-SCF) calculations. A calculation scheme is proposed to simplify the evaluation of integrals and a key equation is derived to reduce the computation efforts in SCF iterations. According to the key equation, compared with the traditional SCF method, the computation efficiencies including CPU timing and external disk (or internal memory) requirement increase in the magnitude of the square of the order of a point group. The new SOT method is expected to be useful in the theoretical calculations of large molecular systems of high point group symmetries. 相似文献
143.
In this paper, a novel reconstruction of the gradient and Hessian tensors on an arbitrary unstructured grid, developed for implementation in a cell‐centered finite volume framework, is presented. The reconstruction, based on the application of Gauss' theorem, provides a fully second‐order accurate estimate of the gradient, along with a first‐order estimate of the Hessian tensor. The reconstruction is implemented through the construction of coefficient matrices for the gradient components and independent components of the Hessian tensor, resulting in a linear system for the gradient and Hessian fields, which may be solved to an arbitrary precision by employing one of the many methods available for the efficient inversion of large sparse matrices. Numerical experiments are conducted to demonstrate the accuracy, robustness, and computational efficiency of the reconstruction by comparison with other common methods. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
144.
Tzonka Mineva 《Journal of Chemical Sciences》2005,117(5):485-490
The third term in the Taylor expansion of the total energy functional around the number of electronsN is evaluated as the second-order derivative of orbital Kohn-Sham energies with respect to orbital occupancy. Present approach
is an extension of an efficient algorithm to compute densityfunctional based orbital reactivity indices. Various energy derivatives
used to approximate orbital reactivity indices are defined within the space spanned by the orbital occupation numbers and
the Kohn-Sham one-electron energies. The third-order energy functional derivative has to be considered for singular hardness
tensor ([η]). On the contrary, this term has negligible influence on the reactivity index values for atomic or molecular systems
with positively defined hardness tensors. In this context, stability of a system in equilibrium state estimated through the
eigenvalues of [η] is discussed. Numerical illustration of the Kohn-Sham energy functional derivatives in orbital resolution
up to the third order is shown for benchmark molecules such as H2O, H2S, and OH−. 相似文献
145.
John M. Myers 《Foundations of Physics》2006,36(7):1012-1035
Motivated by a recent proof of free choices in linking equations to the experiments they describe, I clarify some relations among purely mathematical entities featured in quantum mechanics (probabilities, density operators, partial traces, and operator-valued measures), thereby allowing applications of these entities to the modeling of a wider variety of physical situations. I relate conditional probabilities associated with projection-valued measures to conditional density operators identical, in some cases but not in others, to the usual reduced density operators. While a fatal obstacle precludes associating conditional density operators with general non-projective measures, tensor products of general positive operator-valued measures (POVMs) are associated with conditional density operators. This association together with the free choice of probe particles allows a postulate of state reductions to be replaced by a theorem. An application shows an equivalence between one form of quantum key distribution and another with respect to certain eavesdropping attacks. 相似文献
146.
A potential for the bounded part of the Maxwell tensor associated to the Liénard-Wiechert field has been obtained by van Weert.
In this paper we explicitly derive the non-local potential for the radiative part of such a tensor. 相似文献
147.
Philippe Delanoe 《Annals of Global Analysis and Geometry》1992,10(1):3-61
Existence, uniqueness and weighted regularity of solutions of linear and nonlinear second-order uniformly elliptic differential equations on complete punctured compact N-manifolds, N > 2. Application to prescribed curvature problems: scalar curvature in a quasi-isometry class (including a contribution to the Lichnérowicz-York equation of General Relativity); Ricci curvature in a weighted Kähler class (with a related result in equiaffine geometry). A new asymptonic behaviour is allowed throughout, called partial decay, which requires its own maximum principle.Current support: CNRS; partial support; CEE contract GADGET # SC1-0105-C. 相似文献
148.
Dae- Woong Lee 《数学物理学报(B辑英文版)》2002,(1)
1 IntroductiouLet G and Z be an abelian group and the set Of all integers respectively And letC = (C., ft,', I') denote an inverse system of chain complexes C. and chain maPS I..1: Cv, -Ct,7 5 T' indexed by a directed set r. Strong homology groups HP(C) of the inverse systemC were defilled by J. T. Lisica and S. Mardedie[n. Using the ANRresOlution[9'l1I, algebraictopolOgists defined the strong homology group HP(X; G) of a topological space X with coefficient8 in G and gave exMPl… 相似文献
149.
From the comparison of correlation tensor in the theory of quantum network, the Alexander relation matrix in the theory of knot crystals and the identical inversion relations under the action of Pauli matrices, we show that there is a one to one correspondence between four Bell bases and four oriented links of the linkage 41 in knot theory. 相似文献
150.
王琪 《武汉大学学报(理学版)》2003,49(5):553-555
首先得到一个推广的Simons型积分不等式,然后用它给出共形平坦黎曼流形中紧致极小子流形对外围空间的一个拼挤定理. 相似文献