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arXiv: Functional Analysis最新文献

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Monotone iterative schemes for positive solutions of a fractional differential system with integral boundary conditions on an infinite interval 无穷区间上具有积分边界条件的分数阶微分系统正解的单调迭代格式
Pub Date : 2020-05-18 DOI: 10.2298/FIL2013399L
Yaohong Li, W. Cheng, Jiafa Xu
In this paper, using the monotone iterative technique and the Banach contraction mapping principle, we study a class of fractional differential system with integral boundary on an infinite interval. Some explicit monotone iterative schemes for approximating the extreme positive solutions and the unique positive solution are constructed.
本文利用单调迭代技术和Banach收缩映射原理,研究了一类在无穷区间上具有积分边界的分数阶微分系统。构造了逼近极值正解和唯一正解的显式单调迭代格式。
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引用次数: 1
Jackson theorem and modulus of continuity in Hilbert spaces and on homogeneous manifolds Jackson定理与Hilbert空间和齐次流形上的连续性模
Pub Date : 2020-05-17 DOI: 10.1007/s10476-022-0176-0.pdf
I. Pesenson
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引用次数: 0
Birkhoff–James Orthogonality and Applications: A Survey Birkhoff-James正交性及其应用综述
Pub Date : 2020-05-15 DOI: 10.1007/978-3-030-51945-2_15
Priyanka Grover, Sushil Singla
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引用次数: 8
Hausdorff measure of critical set for Luzin N condition Luzin N条件下临界集的Hausdorff测度
Pub Date : 2020-05-13 DOI: 10.1016/j.jmaa.2020.124528
Anna Doležalová, Marika Hrubešová, T. Roskovec
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引用次数: 0
Some bounds for the $mathbb{A}$-numerical radius of certain $2 times 2$ operator matrices 某些$2 乘以2$算子矩阵的$mathbb{A}$数值半径的一些界
Pub Date : 2020-05-12 DOI: 10.15672/HUJMS.730574
Kais Feki
For a given bounded positive (semidefinite) linear operator $A$ on a complex Hilbert space $big(mathcal{H}, langle cdotmid cdotrangle big)$, we consider the semi-Hilbertian space $big(mathcal{H}, langle cdotmid cdotrangle_A big)$ where ${langle xmid yrangle}_A := langle Axmid yrangle$ for every $x, yinmathcal{H}$. The $A$-numerical radius of an $A$-bounded operator $T$ on $mathcal{H}$ is given by begin{align*} omega_A(T) = supBig{big|{langle Txmid xrangle}_Abig|,; ,,xin mathcal{H}, ,{langle xmid xrangle}_A= 1Big}. end{align*} Our aim in this paper is to derive several $mathbb{A}$-numerical radius inequalities for $2times 2$ operator matrices whose entries are $A$-bounded operators, where $mathbb{A}=text{diag}(A,A)$.
对于给定的有界正(半定)线性算子 $A$ 在复希尔伯特空间上 $big(mathcal{H}, langle cdotmid cdotrangle big)$,我们考虑半希尔伯特空间 $big(mathcal{H}, langle cdotmid cdotrangle_A big)$ 在哪里 ${langle xmid yrangle}_A := langle Axmid yrangle$ 对于每一个 $x, yinmathcal{H}$. The $A$- an的数值半径 $A$-有界算子 $T$ on $mathcal{H}$ 是由 begin{align*} omega_A(T) = supBig{big|{langle Txmid xrangle}_Abig|,; ,,xin mathcal{H}, ,{langle xmid xrangle}_A= 1Big}. end{align*} 本文的目的是推导出几个 $mathbb{A}$-数值半径不等式 $2times 2$ 算子矩阵的项是 $A$-有界算子,其中 $mathbb{A}=text{diag}(A,A)$.
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引用次数: 5
A class of Integral Operators from Lebesgue spaces into Harmonic Bergman-Besov or Weighted Bloch Spaces 一类从Lebesgue空间到调和Bergman-Besov或加权Bloch空间的积分算子
Pub Date : 2020-05-10 DOI: 10.15672/HUJMS.768123
Ö. Doğan
We consider a class of two-parameter weighted integral operators induced by harmonic Bergman-Besov kernels on the unit ball of $mathbb{R}^{n}$ and characterize precisely those that are bounded from Lebesgue spaces $L^{p}_{alpha}$ into Harmonic Bergman-Besov $b^{q}_{beta}$ or weighted Bloch Spaces $b^{infty}_{beta} $, for $1leq pleqinfty$, $1leq q -1$ when $q
我们考虑了在$mathbb{R}^{n}$的单位球上由调和Bergman-Besov核诱导的一类两参数加权积分算子,并精确地描述了那些从Lebesgue空间$L^{p}_{alpha}$入调和Bergman-Besov $b^{q}_{beta}$或加权Bloch空间$b^{infty}_{beta} $的算子,对于$1leq pleqinfty$,通过将算子映射到这些空间而不是映射到Lebesgue类上的调和Bergman-Besov核诱导的一类积分算子$1leq q -1$ when $q
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引用次数: 0
A short proof of the infinitesimal Hilbertianity of the weighted Euclidean space 加权欧几里得空间的无穷小希尔伯性的一个简短证明
Pub Date : 2020-05-06 DOI: 10.5802/crmath.88
Simone Di Marino, Danka Luvci'c, Enrico Pasqualetto
We provide a quick proof of the following known result: the Sobolev space associated with the Euclidean space, endowed with the Euclidean distance and an arbitrary Radon measure, is Hilbert. Our new approach relies upon the properties of the Alberti-Marchese decomposability bundle. As a consequence of our arguments, we also prove that if the Sobolev norm is closable on compactly-supported smooth functions, then the reference measure is absolutely continuous with respect to the Lebesgue measure.
我们提供了以下已知结果的一个快速证明:索博列夫空间与欧几里得空间相关联,具有欧几里得距离和任意Radon测度,是希尔伯特。我们的新方法依赖于Alberti-Marchese分解束的性质。作为我们论证的结果,我们也证明了如果Sobolev范数在紧支持光滑函数上是闭的,那么参考测度相对于Lebesgue测度是绝对连续的。
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引用次数: 9
Invariant subspaces for positive operators on Banach spaces with unconditional basis 带无条件基的Banach空间上正算子的不变子空间
Pub Date : 2020-05-03 DOI: 10.1090/proc/16026
Eva A. Gallardo-Guti'errez, Javier Gonz'alez-Dona, P. Tradacete
We prove that every lattice homomorphism acting on a Banach space $mathcal{X}$ with the lattice structure given by an unconditional basis has a non-trivial closed invariant subspace. In fact, it has a non-trivial closed invariant ideal, which is no longer true for every positive operator on such a space. Motivated by these later examples, we characterize tridiagonal positive operators without non-trivial closed invariant ideals on $mathcal{X}$ extending to this context a result of Grivaux on the existence of non-trivial closed invariant subspaces for tridiagonal operators.
证明了作用于Banach空间$mathcal{X}$上的每个格同态具有一个非平凡闭不变子空间。事实上,它有一个非平凡的闭不变量理想,它不再对这样一个空间上的每一个正算子都成立。在这些例子的激励下,我们刻画了$mathcal{X}$上没有非平凡闭不变量理想的三对角正算子,将Grivaux关于三对角算子非平凡闭不变量子空间存在性的结论推广到这一背景下。
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引用次数: 0
Spaces 𝐶(𝐾) with an equivalent URED norm 用等价的URED范数空格(𝐾)
Pub Date : 2020-04-30 DOI: 10.1090/proc/15315
A. Avil'es, S. Troyanski
We prove that a Banach space of continuous functions $C(K)$ has a renorming that is uniformly rotund in every direction (URED) if and only if the compact space $K$ supports a strictly positive measure
我们证明了连续函数的Banach空间$C(K)$有一个在各方向上一致圆的重整当且仅当紧化空间$K$支持一个严格正测度
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引用次数: 1
Lipschitz free spaces over locally compact metric spaces 局部紧化度量空间上的Lipschitz自由空间
Pub Date : 2020-04-24 DOI: 10.4064/SM200511-10-10
C. Gartland
We prove that the Lipschitz free space over a certain type of discrete metric space has the Radon-Nikodým property. We also show that the Lipschitz free space over a complete, locally compact metric space has the Schur or approximation property whenever the Lipschitz free space over each compact subset also has this property.
证明了一类离散度量空间上的Lipschitz自由空间具有Radon-Nikodým性质。我们还证明了完备的,局部紧化度量空间上的Lipschitz自由空间具有舒尔或近似性质,而每个紧化子集上的Lipschitz自由空间也具有这个性质。
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引用次数: 2
期刊
arXiv: Functional Analysis
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