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1.
Banach压缩映象原理与空间完备性   总被引:3,自引:0,他引:3  
本文进一步揭示了Banach压缩映象原理与完备性的关系,指出:一般地,Banach压缩映象原理等价于道路完备性,在一定条件下才等价于完备性,进一步给出了这一等价性成立的充要条件  相似文献   

2.
The paper addresses the completeness of sines and cosines with non-integer indices in the space of Lebesgue-integrable functions. The criteria for the variation from the integer value have been found such that sine and cosine systems are complete.  相似文献   

3.
We study the following question: does a compact nonpositively curved space have a totally geodesic core?  相似文献   

4.
We propose geometric conditions equivalent to the discreteness of the spectrum of the Laplacian on a class of Riemannian manifolds with ends close to warped products. For this class of manifolds we establish a relationship between discreteness of the spectrum and stochastic incompleteness.   相似文献   

5.
We prove that the stochastic completeness of a Riemannian manifold is equivalent to the validity of a weak form of the Omori-Yau maximum principle. Some geometric applications of this result are also presented.

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6.
Given a bounded convex domain Ω with C∞ boundary and a function ψ∈C∞(δΩ), Li-Simon-Chen can construct an Euclidean complete and W-complete convex hypersurface M with constant affine Gauss-Kronecker curvature, and they guess the M is also affine complete. In this paper, we give a confirmation answer.  相似文献   

7.
We survey algebraic results on combinatorial circuits constructed from many-valued uniformly delayed gates. These involve the composition of uniformly delayed operations, the lattice of uniform clones, the corresponding relational theory, uniform completeness and the search for an effective completeness criterion.  相似文献   

8.
We look at geodesic foliations on the Lorentzian 2-tori which are lightlike on a proper subset. We prove that they do not exist if the torus is geodesically complete. We describe some properties of their orthogonal foliations and we give several new examples.   相似文献   

9.
An algebraic setting for the validity of Pavelka style completeness for some natural expansions of Łukasiewicz logic by new connectives and rational constants is given. This algebraic approach is based on the fact that the standard MV-algebra on the real segment [0, 1] is an injective MV-algebra. In particular the logics associated with MV-algebras with product and with divisible MV-algebras are considered. The author express his gratitude to Roberto Cignoli, for his advice during the preparation of this paper.  相似文献   

10.
We prove an extension of Ekeland's variational principle to locally complete spaces which uses subadditive, strictly increasing continuous functions as perturbations.  相似文献   

11.
We study the completeness properties of the set of wavelets in . It is well-known that this set is not closed in the unit ball of . However, if one considers the metric inherited as a subspace (in the Fourier transform side) of , we do obtain a complete metric space.

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12.
距离空间X上,以M(X)记定义在X的Borel域上的具有有界支撑的概度测度全体,R(X)记M(X)中所有Radon测度,M(X),R(X)均赋予Hutchison度量,本文得到:R(X)完备当且仅当X完备且有界,若X可分,则:M(X)完备当且仅当X完备且有界。  相似文献   

13.
We consider some systems of exponential functions, cosines, and sines with complex-valued coefficients and establish a necessary and sufficient condition for completeness and minimality of these systems in Lebesgue spaces.  相似文献   

14.
For , the eigenfunctions of the non-linear eigenvalue problem for the -Laplacian on the interval are shown to form a Riesz basis of and a Schauder basis of whenever .

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15.
杨舟  宁刚 《大学数学》2012,28(2):121-125
从"距离"的角度来描述和理解数学分析中有关实数的一些概念和定理,并作出相关的证明,特别给出实数完备性的一个新的描述.  相似文献   

16.
We prove in the framework of Bishop's constructive mathematics that the sequential completion $ \tilde {\cal D} $(?) of the space ??(?) is filter‐complete. Then it follows as a corollary that the filter‐completeness of ??(?) is equivalent to the principle BD‐?, which can be proved in classical mathematics, Brouwer's intuitionistic mathematics and constructive recursive mathematics of Markov's school, but does not in Bishop's constructive mathematics. We also show that $ \tilde {\cal D} $(?) is identical with the filter‐completion which was provided by Bishop. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

17.
Let B be an unbounded domain located outside an angle domain with vertex at the origin, A ={λn}(n = 1,2,...) be a sequence of complex numbers satisfying sup | arg(λn)| 〈 α 〈 π/2 and denote by M(∧) = {z^λ, λ ∈ ∧} the corresponding system of functions z^λ(λ∈∧). Let α0(z) be a weight function defined on B. We obtain a completeness theorem for the system M(∧) in the Hilbert space L^2 [B, α0].  相似文献   

18.
Weighted exponential polynomial approximation   总被引:7,自引:0,他引:7  
A necessary and sufficient condition for completeness of systems of exponentials with a weight in Lp is established and a quantitative relation between the weight and the system of exponential in Lp is obtained by using a generalization of Malliavin's uniqueness theorem about Watson's problem.  相似文献   

19.
本文研究了标的资产价格服从连续时间It过程模型的金融市场的完备性问题。在允许有摩擦的金融市场中,当可允许投资策略取值于一个非空凸闭集时,给出了金融市场在内蕴完备条件下广义不完备的充分必要条件.  相似文献   

20.
A necessary and sufficient condition is obtained for the complex exponential system to be dense in the weighted Banach space Lpα = {f : f∞-∞ |f(t)e-α(t)|pdt ∞}, where 1 ≤ p + ∞and α(t) is a nonnegative continuous function on R.  相似文献   

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