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51.
Giacomo Fonte 《Theoretical chemistry accounts》1981,59(5):533-549
We investigate the analytical convergence of SCF and MCSCF calculations, when the dimension of the subspaces to which the orbitals are restricted tends to infinity. We show that the completeness only inL
2(R
3;C
2) of the orbital bases does not ensure the convergence of the Ritz-energy, neither in SCF nor in MCSCF calculations, but that this convergence — as well as the convergence of the Ritz-orbitals in SCF calculations — is on the contrary guaranteed if the orbital bases are complete in the Sobolev spaceW
1,2(R
3;C
2). Some consequences on the choice of the orbital exponents of Slater and Gauss functions are also discussed. 相似文献
52.
Carsten Held 《Foundations of Physics》2008,38(8):707-732
The standard axiomatization of quantum mechanics (QM) is not fully explicit about the role of the time-parameter. Especially,
the time reference within the probability algorithm (the Born Rule, BR) is unclear. From a probability principle P1 and a
second principle P2 affording a most natural way to make BR precise, a logical conflict with the standard expression for the
completeness of QM can be derived. Rejecting P1 is implausible. Rejecting P2 leads to unphysical results and to a conflict
with a generalization of P2, a principle P3. All three principles are shown to be without alternative. It is thus shown that
the standard expression of QM completeness must be revised. An absolutely explicit form of the axioms is provided, including
a precise form of the projection postulate. An appropriate expression for QM completeness, reflecting the restrictions of
the Gleason and Kochen-Specker theorems is proposed. 相似文献
53.
Direct and inverse problems of spectral analysis are studied for an indefinite singular boundary value problem coming from astrophysics. We establish properties of the spectrum, prove completeness and expansion theorems and investigate the inverse problem of recovering the differential equation from the given spectral characteristics. 相似文献
54.
研究了一个基于模糊偏好关系的模糊选择函数。首先对文献中基于普通关系的最好元集所确定的选择函数进行了回顾,并给出了进一步结果。然后,讨论了该选择函数的模糊化形式,给出了基于模糊偏好的选择集确定模糊选择函数的充要条件,同时研究了该选择函数的合理性性质。 相似文献
55.
56.
This paper introduces the concept of the square-mean pseudo almost automorphy for a stochastic process. Also it introduces the properties on the completeness and the composition of the space that consists of such processes. With appropriate settings and by virtue of the theory of the semigroups of the operators to an evolution family, the Banach fixed point theorem and the stochastic analysis techniques, this paper investigates the existence, the uniqueness and the global stability of the square-mean pseudo almost automorphic solutions for a general class of stochastic evolution equations. Finally, this paper provides an illustrative example to justify the practical usefulness of the established theoretical results. 相似文献
57.
In this article, singular dissipative operators with finite impulsive conditions are investigated. In particular, after passing to the inverse operators, it is obtained that the imaginary parts of the inverse operators are nuclear. Finally, using Krein's theorem, it is proved that all root vectors of the singular dissipative operators with finite impulsive conditions are complete in the Hilbert space. 相似文献
58.
We set up a generic framework for proving completeness results for variants of the modal mu-calculus, using tools from coalgebraic modal logic. We illustrate the method by proving two new completeness results: for the graded mu-calculus (which is equivalent to monadic second-order logic on the class of unranked tree models), and for the monotone modal mu-calculus.Besides these main applications, our result covers the Kozen–Walukiewicz completeness theorem for the standard modal mu-calculus, as well as the linear-time mu-calculus and modal fixpoint logics on ranked trees. Completeness of the linear-time mu-calculus is known, but the proof we obtain here is different and places the result under a common roof with Walukiewicz' result.Our approach combines insights from the theory of automata operating on potentially infinite objects, with methods from the categorical framework of coalgebra as a general theory of state-based evolving systems. At the interface of these theories lies the notion of a coalgebraic modal one-step language. One of our main contributions here is the introduction of the novel concept of a disjunctive basis for a modal one-step language. Generalizing earlier work, our main general result states that in case a coalgebraic modal logic admits such a disjunctive basis, then soundness and completeness at the one-step level transfer to the level of the full coalgebraic modal mu-calculus. 相似文献
59.
It is known since 1973 that Lawvere’s notion of Cauchy-complete enriched category is meaningful for metric spaces: it captures
exactly Cauchy-complete metric spaces. In this paper, we introduce the corresponding notion of Lawvere completeness for
(\mathbbT,V)(\mathbb{T},\mathsf{V})-categories and show that it has an interesting meaning for topological spaces and quasi-uniform spaces: for the former ones
it means weak sobriety while for the latter it means Cauchy completeness. Further, we show that V\mathsf{V} has a canonical
(\mathbbT,V)(\mathbb{T},\mathsf{V})-category structure which plays a key role: it is Lawvere-complete under reasonable conditions on the setting; this structure
permits us to define a Yoneda embedding in the realm of
(\mathbbT,V)(\mathbb{T},\mathsf{V})-categories. 相似文献
60.
In this paper, we define a realizability semantics for the simply typed λμ-calculus. We show that, if a term is typable, then it inhabits the interpretation of its type. This result serves to give characterizations of the computational behavior of some closed typed terms. We also prove a completeness result of our realizability semantics using a particular term model. 相似文献