共查询到20条相似文献,搜索用时 31 毫秒
1.
V. B. Sherstyukov 《Siberian Mathematical Journal》2010,51(4):745-754
We establish a dual criterion for absolutely representing systems in the spaces of a sufficiently broad class of inductive
limits of sequences of Banach spaces. The result is stated without any additional restrictions on the system. We consider
applications to the systems of partial fractions in the spaces of locally analytic functions. 相似文献
2.
Jesús M. Fdez Castillo 《Monatshefte für Mathematik》1988,105(1):43-46
We give a new proof of a result of Benndorf about the convergence conditions one can obtain for sequences of operators defining the BAP (resp. FDD) in Fréchet Schwartz spaces. We also obtain an even stronger result for DF co-Schwartz spaces, dualizing in this way Benndorf's result. 相似文献
3.
Eugenio Hern��ndez Jos�� Mar��a Martell Maria de Natividade 《Constructive Approximation》2011,33(1):1-14
We study the efficiency of the greedy algorithm for wavelet bases in Lorentz spaces in order to give the near best approximation.
The result is used to give sharp inclusions for the approximation spaces in terms of discrete Lorentz sequence spaces. 相似文献
4.
We obtain continuous-time and discrete-time Lyapunov operator inequalities for the exponential stability of strongly continuous, one-parameter semigroups acting on Banach spaces. Thus we extend the classic result of Datko (1970) [2] from Hilbert spaces to Banach spaces. 相似文献
5.
Craig Westerland 《Topology and its Applications》2006,153(15):2834-2865
We study the homotopy type of mapping spaces from Riemann surfaces to spheres. Our main result is a stable splitting of these spaces into a bouquet of new finite spectra. From this and classical results, one may deduce splittings of the configuration spaces of surfaces. 相似文献
6.
证明了赋范空间单位球之间任意保一的1-Lipshcitz算子在假设像空间是严格凸的,或者算子是满的条件下是定义在全空间上的线性等距算子在单位球上的限制.同时,也给出了这个结果的一些应用,以及当两个赋范空间是严格凸时推广了的结果. 相似文献
7.
Positivity - We develop and apply a decomposition theory for generic local Morrey-type spaces. Our result is nonsmooth decomposition, which follows from the fact that local Morrey-type spaces are... 相似文献
8.
Frame multiresolution analysis and infinite trees in Banach spaces on locally compact abelian groups
S.S.Panday 《分析论及其应用》2004,20(3):231-241
We extend the concept of frame multiresolution analysis to a locally compact abelian group and use it to define certain weighted Banach spaces and the spaces of their antifunctionals. We define analysis and synthesis operators on these spaces and establish the continuity of their composition. Also, we prove a general result to characterize infinite trees in the above Banach spaces of antifunctionals. This paper paves the way for the study of corresponding problems associated with some other types of Banach spaceson locally compact abelian groups including modulation spaces. 相似文献
9.
Jérôme Poineau 《Mathematische Annalen》2014,358(3-4):949-970
We investigate affine Berkovich spaces over maximally complete fields and prove that they may be approximated by simpler spaces when the only functions we need to evaluate are polynomials with bounded degrees. We derive applications to semi-algebraic sets and recover a result of E. Hrushovski and F. Loeser claiming that points of Berkovich spaces give rise to definable types (a model-theoretic notion of tameness). 相似文献
10.
We prove an equivalence result between the validity of a pointwise Hardy inequality in a domain and uniform capacity density
of the complement. This result is new even in Euclidean spaces, but our methods apply in general metric spaces as well. We
also present a new transparent proof for the fact that uniform capacity density implies the classical integral version of
the Hardy inequality in the setting of metric spaces. In addition, we consider the relations between the above concepts and
certain Hausdorff content conditions. 相似文献
11.
Summary We present new properties of the Besov--Hankel spaces introduced in [10]. We prove a Hankel version of a result of Bui, Paluszyński
and Taibleson obtaining new norms that define the topology of the Besov--Hankel spaces. Also we get atomic representations
for the distributions in the spaces under consideration. 相似文献
12.
S. Dhompongsa A. Kaewkhao B. Panyanak 《Nonlinear Analysis: Theory, Methods & Applications》2012,75(2):459-468
We prove a strong convergence theorem for multivalued nonexpansive mappings which includes Kirk’s convergence theorem on CAT(0) spaces. The theorem properly contains a result of Jung for Hilbert spaces. We then apply the result to approximate a common fixed point of a countable family of single-valued nonexpansive mappings and a compact valued nonexpansive mapping. 相似文献
13.
A well-known result going back to the 1930s states that all bounded linear operators mapping scalar-valued L
1-spaces into L
∞-spaces are kernel operators and that in fact this relation induces an isometric isomorphism between the space of such operators
and the space of all bounded kernels. We extend this result to the case of spaces of vector-valued functions. A recent result
due to Arendt and Thomaschewski states that the local operators acting on L
p
-spaces of functions with values in separable Banach spaces are precisely the multiplication operators. We extend this result
to non-separable dual spaces. Moreover, we relate positivity and other order properties of the operators to corresponding
properties of the representations. 相似文献
14.
G. M. Kuz'mina 《Mathematical Notes》1974,16(4):961-963
We introduce a class of Riemann structures, called generalized Einstein structures of index 2e, of which Einstein spaces are a particular case. We show that these structures are stationary for functions introduced on a family of Riemann structures of the compact manifold of H. Weyl. This result solves a problem of M. Berger. As examples of structures which are generalized Einstein structures over all indices we cite homogeneous compact Riemann spaces with a nondecomposable isotropy group and products of such spaces. 相似文献
15.
Jos�� Luis Romero 《Journal of Fourier Analysis and Applications》2011,17(1):135-174
We prove a result about producing new frames for general spline-type spaces by piecing together portions of known frames. Using spline-type spaces as models for the range of certain integral transforms, we obtain results for time-frequency decompositions and sampling. 相似文献
16.
Nina Zorboska 《Proceedings of the American Mathematical Society》1998,126(7):2013-2023
We characterize bounded and compact composition operators on weighted Dirichlet spaces. The method involves integral averages of the determining function for the operator, and the connection between composition operators on Dirichlet spaces and Toeplitz operators on Bergman spaces. We also present several examples and counter-examples that point out the borderlines of the result and its connections to other themes.
17.
We prove the existence of continuous boundary extensions (Cannon-Thurston maps) for the inclusion of a vertex space into a
tree of (strongly) relatively hyperbolic spaces satisfying the qi-embedded condition. This implies the same result for inclusion
of vertex (or edge) subgroups in finite graphs of (strongly) relatively hyperbolic groups. This generalizes a result of Bowditch
for punctured surfaces in 3 manifolds and a result of Mitra for trees of hyperbolic metric spaces. 相似文献
18.
A result of Aliprantis and Burkinshaw shows that weakly compact operators from an AL-space into a KB-space have a weakly compact modulus. Groenewegen characterised the largest class of range spaces for which this remains true whenever the domain is an AL-space and Schmidt proved a dual result. Both of these authors used vector-valued integration in their proofs. We give elementary proofs of both results and also characterise the largest class of domains for which the conclusion remains true whenever the range space is a KB-space. We conclude by studying the order structure of spaces of weakly compact operators between Banach lattices to prove results analogous to earlier results of one of the authors for spaces of compact operators.
19.
We derive Banach-Stone theorems for spaces of homogeneous polynomials. We show that every isometric isomorphism between the spaces of homogeneous approximable polynomials on real Banach spaces E and F is induced by an isometric isomorphism of E′ onto F′. With an additional geometric condition we obtain the analogous result in the complex case. Isometries between spaces of homogeneous integral polynomials and between the spaces of all n-homogeneous polynomials are also investigated. 相似文献
20.
Vladislav Chernysh 《Proceedings of the American Mathematical Society》2006,134(9):2771-2777
In this paper we show that for Riemannian manifolds with boundary the natural restriction map is a quasifibration between spaces of metrics of positive scalar curvature. We apply this result to study homotopy properties of spaces of such metrics on manifolds with boundary.