共查询到20条相似文献,搜索用时 15 毫秒
1.
Spiros A. Argyros 《Proceedings of the American Mathematical Society》2001,129(11):3231-3239
It is shown that every separable Banach space universal for the class of reflexive Hereditarily Indecomposable space contains isomorphically and hence it is universal for all separable spaces. This result shows the large variety of reflexive H.I. spaces.
2.
利用S. Brown技巧,在稍微增加了一点谱的厚度的情形下证明了Mohebi-Radjabalipour猜想,得到了序列次可分解算子的两个不变子空间定理. 作为特殊情形该结果包含了H. Mohebi 和 M. Radjabalipour得到的一个重要的不变子空间定理. 相似文献
3.
Niels Jakob Laustsen 《K-Theory》2001,22(3):241-249
Let
Figiel's reflexive Banach space which is not isomorphic to its Cartesian square. We show that the K
0group of the algebra
of continuous, linear operators on
contain a subgroup isomorphic to the group c
00(
) of sequences
rational numbers with z
n=0 eventually. 相似文献
4.
On K_0-groups of operator algebras on Banach spaces 总被引:1,自引:0,他引:1
ZHANG Yunnan ZHONG Huaijie & SU Weigang School of Mathematics Computer Science Fujian Normal University Fuzhou China 《中国科学A辑(英文版)》2006,49(2)
This paper merges some classifications of G-M-type Banach spaces simplifically, discusses the condition of K0(B(X)) = 0 for operator algebra B(X) on a Banach space X, and obtains a result to improve Laustsen's sufficient condition, gives an example to show that X ≈ X2 is not a sufficient condition of K0(B(X)) = 0. 相似文献
5.
B. S. Zakirov 《Siberian Advances in Mathematics》2009,19(2):128-149
We consider the Orlicz-Kantorovich modules L M (?,m) associated with a complete Boolean algebra ?, an N-function M, and a measure m defined on ? and taking values in the algebra L 0 of all measurable real functions. We obtain an analytic representation of the continuous L 0-valued homomorphisms defined on such modules. 相似文献
6.
A clarified study on the G-complete symmetry Banach algebra is given. A Wiener type Banach algebra as well as its stucture is introduced and studied. An application of this algebra is presented. 相似文献
7.
Huang Jianfeng Wang Yuanheng 《高校应用数学学报(英文版)》2007,22(3):311-315
This paper studies the convergence of the sequence defined by x0∈C,xn 1=αnu (1-αn)Txn,n=0,1,2,…, where 0 ≤αn ≤ 1, limn→∞αn = 0, ∑∞n=0 αn = ∞, and T is a nonexpansive mapping from a nonempty closed convex subset C of a Banach space X into itself. The iterative sequence {xn} converges strongly to a fixed point of T in the case when X is a uniformly convex Banach space with a uniformly Gateaux differentiable norm or a uniformly smooth Banach space only. The results presented in this paper extend and improve some recent results. 相似文献
8.
《Indagationes Mathematicae》2019,30(5):930-942
We extend the notions of -convexity and -concavity for Banach ideals of measurable functions following an asymptotic procedure. We prove a representation theorem for the spaces satisfying both properties as the one that works for the classical case: each almost -convex and almost -concave space is order isomorphic to an almost--space. The class of almost--spaces contains, in particular, direct sums of (infinitely many) -spaces with different norms, that are not in general -convex – nor -concave –. We also analyze in this context the extension of the Maurey–Rosenthal factorization theorem that works for -concave operators acting in -convex spaces. In this way we provide factorization results that allow to deal with more general factorization spaces than -spaces. 相似文献
9.
10.
Niels Jakob Laustsen 《K-Theory》2001,23(2):115-127
We prove that the K-groups of the Banach algebra
of bounded, linear operators on the pth James space
, where 1 < p < , are given by
and
. Moreover, for each Banach space
and each non-zero, closed ideal
contained in the ideal of inessential operators, we show that
and
. This enables us to calculate the K-groups of
for each Banach space
which is a direct sum of finitely many James spaces and
-spaces. 相似文献
11.
In this note we give generalizations of Noguchi's convergence-extension theorem to the case of infinite dimension.
12.
Jean B. Lasserre 《Proceedings of the American Mathematical Society》1998,126(1):189-194
We consider a linear sytem in a Banach lattice and provide a simple theorem of the alternative (or Farkas lemma) without the usual closure condition.
13.
Valentin Ferenczi 《Journal of Functional Analysis》2009,257(1):149-1060
We prove three new dichotomies for Banach spaces à la W.T. Gowers' dichotomies. The three dichotomies characterise respectively the spaces having no minimal subspaces, having no subsequentially minimal basic sequences, and having no subspaces crudely finitely representable in all of their subspaces. We subsequently use these results to make progress on Gowers' program of classifying Banach spaces by finding characteristic spaces present in every space. Also, the results are used to embed any partial order of size ℵ1 into the subspaces of any space without a minimal subspace ordered by isomorphic embeddability. 相似文献
14.
ZHONG Huaijie CHEN Dongxiao CHEN Jianlan Department of Mathematics Fujian Normal University Fuzhou China 《中国科学A辑(英文版)》2004,47(3):372-392
By providing several new varieties of G-M-type Banach spaces according todecomposable and compoundable properties, this paper discusses the operator structuresof these spaces and the K-theory of the algebra of the operators on these G-M-type Ba-nach spaces through calculation of the K-groups of the operator ideals contained in theclass of Riesz operators. 相似文献
15.
Banach空间单位球面的球覆盖性质 总被引:5,自引:2,他引:3
证明了n维Banach空间的单位球面最少可被2n个不含原点的半径相同的球对称覆盖,并计算了空间(Rn,‖·‖2)中,单位球面可被∪in=1B(±rxi,r)(其中r∈R ,xi∈SX)覆盖时,r的最小值是2n,且球心{xi}ni=1构成了Rn的一组正交基. 相似文献
16.
本文的目标是利用凸性指标给出Banach空间具有Banach-Sake性质的一个充分条件,从而推广Kankutani定理。 相似文献
17.
Fré dé ric Gourdeau Michael C. White 《Transactions of the American Mathematical Society》2001,353(5):2003-2017
We show that . We first use the Connes-Tzygan exact sequence to prove that this is equivalent to the vanishing of the third cyclic cohomology group , where is the non-unital Banach algebra , and then prove that .
18.
For any finite commutative idempotent semigroup S, a semilattice, we show how to compute the amenability constant of its semigroup algebra ℓ
1(S). This amenability constant is always of the form 4n+1. We then show that these give lower bounds to amenability constants of certain Banach algebras graded over semilattices.
We also give example of a commutative Clifford semigroups G
n
whose semigroup algebras ℓ
1(G
n
) admit amenability constants of the form 41+4(n−1)/n. We also show there is no commutative semigroup whose semigroup algebra has an amenability constant between 5 and 9.
N. Spronk’s research was supported by NSERC Grant 312515-05. 相似文献
19.
20.
We study relations between Schatten classes and product operator ideals, where one of the factors is the Banach ideal ΠE,2 of (E, 2)‐summing operators, and where E is a Banach sequence space with ?2 ? E. We show that for a large class of 2‐convex symmetric Banach sequence spaces the product ideal ΠE,2 ○ ??aq,s is an extension of the Schatten class ??F with a suitable Lorentz space F. As an application, we obtain that if 2 ≤ p, q < ∞, 1/r = 1/p + 1/q and E is a 2‐convex symmetric space with fundamental function λE(n) ≈? n1/p, then ΠE,2 ○ Πq is an extension of the Schatten class ??r,q (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献