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1.
PREDUAL SPACES FOR Q SPACES   总被引:2,自引:2,他引:0  
To find the predual spaces Pα(R^n) of Qα(R^n) is an important motivation in the study of Q spaces. In this article, wavelet methods are used to solve this problem in a constructive way. First, an wavelet tent atomic characterization of Pα(Rn) is given, then its usual atomic characterization and Poisson extension characterization are given. Finally, the continuity on Pα of Calderon-Zygmund operators is studied, and the result can be also applied to give the Morrey characterization of Pα(Rn).  相似文献   

2.
《Quaestiones Mathematicae》2013,36(2):171-175
Abstract

If every infinite closed subset of the Wallman compactification, WX, of a space X must contain at least one element of X, then for any space Y intermediate between X and WX the Wallman compactification WY is homeomorphic to WX. This extends a property which characterizes normality inducing spaces. In the case where X is not normal, however, this is not a characterization, since there are nonnormal spaces for which all intermediate spaces are Wallman equivalent, but have infinite closed subsets contained in WX/X.  相似文献   

3.
Abstract

Császár generalized the uniform spaces, the proximity spaces and the topological spaces to syntopogenous spaces. Cook and Fischer generalized the uniform spaces to uniform limit spaces. Finally Marny generalized the proximity spaces to proximal limit spaces. Analogously we generalize the syntopogenous spaces to syntopoformic spaces (syntopogenous limit spaces). These spaces include all the above mentioned in a suitable sense. We extend some of the well-known results of compactness and completeness to syntopoformic spaces.  相似文献   

4.
5.
In this article, we give the sufficient and necessary conditions for which several important mapping spaces are weak dense in the corresponding completely bound mapping spaces.  相似文献   

6.
《Quaestiones Mathematicae》2013,36(2):201-212
Abstract

In this paper we define a special type of H-locally convex space—H-ultrabornological space -. We shall characterize those H-locally convex spaces in terms of linear maps and of inductive limits.  相似文献   

7.
Suppose μ is a Radon measure on Rd, which may be non doubling. The only condition assumed on μ is a growth condition, namely, there is a constant Co > 0 such that for all x ∈ supp(μ) and r > 0,μ(B(x,r)) ≤ Corn, where 0 < n ≤ d. We prove T1 theorem for non doubling measures with weak kernel conditions. Our approach yields new results for kernels satisfying weakened regularity conditions, while recovering previously known Tolsa's results. We also prove T1 theorem for Besov spaces on nonhomogeneous spaces with weak kernel conditions given in [7].  相似文献   

8.
1. IntroductionBy [111, a hypersurface in a symmetric space is called equifocal if every normal geodesicperpendiculajr to it is closed of constant length, say l, and contains Zg focal points for somepositive integer g. This is a natural generalization of isoparametric hypersurfaces in sphereswhere the illteger g is the number of distinct principal curvatures. In this note we considerequifocal hypersurfaces in simply connected rank one symmetric spaces, i.e. the complexprojective space CP", th…  相似文献   

9.
本文将Besov空间Bsp,q推广为精细Besov空间RBap q,其中s∈R,而α∈Rk+1,k为非负整数.给出了精细Besov空间的等价拟范数和嵌入定理.同时证明了在Bsp,q和∪ B;,q之间还存在无t>s穷多个精细Besov空间作为真子空间.  相似文献   

10.
Let(Φ, Ψ) be a pair of complementary N-functions and HΦ(A) and HΨ(A) be the associated noncommutative Orlicz-Hardy spaces. We extend the Riesz, Szeg and innerouter type factorization theorems of Hp(A) to this case.  相似文献   

11.
《Quaestiones Mathematicae》2013,36(1-3):23-43
A concept of normality for nearness spaces is introduced which agrees with the usual normality in the case of topological spaces, is hereditary, and is preserved under the taking of the nearness completion. It is proved that the nearness product of a regular contigual space and a normal nearness space is always normal. The locally fine nearness spaces are studied, particularly in relation to normality conditions.  相似文献   

12.
《代数通讯》2013,41(7):2961-2976
The aim of this paper is to study varieties with second Gauss map not birational. In particular we classify such varieties in dimension two. We prove that there are two types of surfaces S of P n (C), with n > 5, not satisfying Laplace equations, with second Gauss map t 2 not birational: i. surfaces such that the image of the second Gauss map is one-dimensional and containing a one-dimensional family of curves. Each curve of the family is contained in some P 3 ? P n .

ii. surfaces such that the second Gauss map is generically finite of degree at least two. In this case the image of the second Gauss map is two-dimensional, locally embedded in a Laplace congruence and meeting the general generatrix in more than one point.

  相似文献   

13.
《Quaestiones Mathematicae》2013,36(4):439-442
1. Abstract

Most of the well known perturbation results hold for linear operators whose nullity or defect is finite, which implies the existence of topological complements to the null and range spaces respectively. This paper investigates properties associated with the stability of the complementability of the range space under various perturbations.  相似文献   

14.
《Quaestiones Mathematicae》2013,36(4):443-452
Abstract

The proximal limit spaces are introduced which fill the gap arising from the existence of proximity spaces, uniform spaces, and uniform limit spaces. It is shown that the proximal limit spaces can be considered as a bireflective subcategory of the topological category of uniform limit spaces. A limit space is induced by a proximal limit space if and only if it is a S1-limit space.  相似文献   

15.
《Quaestiones Mathematicae》2013,36(3):215-228
Abstract

A categorical characterization of the category Haus of Hausdorft topological spaces within the category Top of topological spaces is given. A notion of a Hausdorff nearness space is then introduced and it is proved that the resulting subcategory Haus Near of the category Near of nearness spaces fulfills exactly the same characterization as derived for Haus in Top. Properties of Haus Near and relations to other important sub-categories of Near are studied.  相似文献   

16.
本文将Besov空间B_P~S,q推广为精细Besov空间RB_P~a,q,其中s∈R,而a∈R~(k+1),k为非负整数.给出了精细Besov空间的等价拟范数和嵌入定理.同时证明了在B_P~S,q和 UB_p~t,q之间还存在无穷多个精细Besov空间作为真子空间.  相似文献   

17.
1Introduction and PreliminariesThroughout this paper,we consider linear spaces over the complex numbers C.Given alinear space X and integers m and n,let Mm,n(X)=X?Mm,n denote the linear space ofm×n matricesx=?????x.x..m1,1,1.x..xm1,n,n?????with entries x…  相似文献   

18.
拟仿紧性与乘积空间   总被引:1,自引:0,他引:1  
本文证明了在V=L假定下,所有正规局部紧拟仿紧空间是仿紧的.并证明了正则拟仿紧性在有限 对一闭映射下是逆保持的.还研究了狭义拟仿紧性的有限乘积和逆极限定理.  相似文献   

19.
Let G be the group of unimodular automorphisms of a free associative ?-algebra on two generators. A theorem of G. Wilson and the first author [BW] asserts that the natural action of G on the Calogero-Moser spaces C n is transitive for all n ? ?. We extend this result in two ways: first, we prove that the action of G on C n is doubly transitive, meaning that G acts transitively on the configuration space of ordered pairs of distinct points in C n ; second, we prove that the diagonal action of G on \( {C}_{n_1}\times {C}_{n_2}\times \cdots \times {C}_{n_m} \) is transitive provided n 1,?n 2,?…,?n m are pairwise distinct numbers.  相似文献   

20.
《Quaestiones Mathematicae》2013,36(3):277-287
ABSTRACT

The purpose of this paper is to investigate pairwise almost compact bitopological spaces. These spaces satisfy a bitopological compactness criterion which is strictly weaker than pairwise C-compactness and is independent of other well-known bitopological compactness notions. Pairwise continuous maps from such spaces to pairwise Hausdorff spaces are pairwise almost closed, the property is invariant under suitably continuous maps, is inherited by regularly closed subspaces and may be characterized in terms of certain covers as well as the adherent convergence of certain open filter bases. Some new natural bitopological separation axioms are introduced and in conjunction with pairwise almost compactness yield interesting results, including a sufficient condition for the bitopological complete separation of disjoint regularly closed sets by semi-continuous functions.  相似文献   

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