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Related papers: Boundedness and closedness of linear relations

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In this paper, we prove that the Cauchy integral operators (or Cauchy transforms) define continuous linear operators on the Smirnov classes for some certain domain with closed analytic boundary.

Functional Analysis · Mathematics 2018-09-05 Yüksel Soykan

Following several papers in the prior literature, we study the relationship between order bounded operators, topologically bounded operators and topologically continuous operators. Our main contribution is two folded: (i) we provide a set…

Functional Analysis · Mathematics 2018-04-12 Liang Hong

We examine the group of isometries of the open unit ball of a complex Banach space of certain bounded linear operators equipped with the Carath\'eodory metric. Therein we obtain a charactrization of the normal isometries in terms of their…

Functional Analysis · Mathematics 2023-03-08 Rachna Aggarwal , Krishnendu Gongopadhyay , Mukund Madhav Mishra

We study properties of classes of closure operators and closure systems parameterized by systems of isotone Galois connections. The parameterizations express stronger requirements on idempotency and monotony conditions of closure operators.…

Logic in Computer Science · Computer Science 2017-01-11 Vilem Vychodil

There are numerous cases of discrepancies between results obtained in the setting of real Banach spaces and those obtained in the complex context. This article is a modern exposition of the subtle differences between key results and…

Functional Analysis · Mathematics 2022-02-25 M. S. Moslehian , G. A. Muñoz-Fernández , A. M. Peralta , J. B. Seoane-Sepúlveda

We carry the index theory for manifolds with boundary of B\"ar and Ballmann over to first order differential operators on metric graphs. This approach results in a short proof for the index of such operators. Then the self-adjoint…

Spectral Theory · Mathematics 2024-03-20 Alberto Richtsfeld

We develop elements of a general dilation theory for operator-valued measures and bounded linear maps between operator algebras that are not necessarily completely-bounded. We prove our main results by extending and generalizing some known…

Operator Algebras · Mathematics 2012-07-23 Deguang Han , David R. Larson , Bei Liu , Rui Liu

We study uniform $\epsilon-$BPB approximations of bounded linear operators between Banach spaces from a geometric perspective. We show that for sufficiently small positive values of $\epsilon,$ many geometric properties like smoothness,…

Functional Analysis · Mathematics 2024-08-14 Debmalya Sain , Arpita Mal , Kalidas Mandal , Kallol Paul

This paper studies approximation properties of linear sampling operators in general Banach lattices $X$. We obtain matching direct and inverse approximation estimates, convergence criteria, equivalence results involving special…

Functional Analysis · Mathematics 2026-01-28 Yurii Kolomoitsev

The scaled relative graph (SRG) of an operator is a subset of the complex plane. It captures several salient features of an operator, such as contractiveness, and can be used to reveal the geometric nature of many of the inequality based…

Optimization and Control · Mathematics 2021-08-05 Richard Pates

The essence of the notion of lineability and spaceability is to find linear structures in somewhat chaotic environments. The existing methods, in general, use \textit{ad hoc} arguments and few general techniques are known. Motivated by the…

Functional Analysis · Mathematics 2015-10-01 Tony K. Nogueira , Daniel Pellegrino

We introduce the class of unbounded $M$-weakly operators and the class of unbounded $L$-weakly compact operators. We investigate some properties for these new classification of operators and we study relation between them and $M$-weakly…

Functional Analysis · Mathematics 2021-09-16 Zahra Niktab , Kazem Haghnejad Azar , Razi Alavizadeh , Saba Sadeghi Gavgani

A banach space X is a normed vector space, which is complete with respect to the metric induced by the norm. Given a bounded linear operator T acting on a banach space X, T is said to attain its norm if there is a unit vector z in X, such…

Functional Analysis · Mathematics 2019-07-30 Samuel Gomez , James Rose , Ryan Maguire

In previous work we established a multilinear duality and factorisation theory for norm inequalities for pointwise weighted geometric means of positive linear operators defined on normed lattices. In this paper we extend the reach of the…

Functional Analysis · Mathematics 2023-05-10 Anthony Carbery , Timo S. Hänninen , Stefán Ingi Valdimarsson

We explain some interesting relations in the degree three bounded cohomology of surface groups. Specifically, we show that if two faithful Kleinian surface group representations are quasi-isometric, then their bounded fundamental classes…

Geometric Topology · Mathematics 2020-05-13 James Farre

We explore the relation between lattice versions of strict singularity for operators from a Banach lattice to a Banach space. In particular, we study when the class of disjointly strictly singular operators, those not invertible on the span…

Functional Analysis · Mathematics 2014-10-20 Julio Flores , Jordi López-Abad , Pedro Tradacete

We apply the Ramsey theory to the analysis of geometrical properties of closed contours. Consider a set of six points placed on a closed contour. The straight lines connecting these points are y_ik (x)={\alpha}_ik x+\b{eta}_ik (i,k=1...6),…

Dynamical Systems · Mathematics 2022-12-21 Nir Shvalb , Mark Frenkel , Shraga Shoval , Edward Bormashenko

In this paper, the problems of perturbation and expression for the Moore--Penrose metric generalized inverses of bounded linear operators on Banach spaces are further studied. By means of certain geometric assumptions of Banach spaces, we…

Functional Analysis · Mathematics 2013-02-14 Jianbing Cao , Yifeng Xue

The aim of this manuscript is to study \emph{spear operators}: bounded linear operators $G$ between Banach spaces $X$ and $Y$ satisfying that for every other bounded linear operator $T:X\longrightarrow Y$ there exists a modulus-one scalar…

Functional Analysis · Mathematics 2018-04-19 Vladimir Kadets , Miguel Martin , Javier Meri , Antonio Perez

Notion of frames and Bessel sequences for metric spaces have been introduced. This notion is related with the notion of Lipschitz free Banach spaces. \ It is proved that every separable metric space admits a metric $\mathcal{M}_d$-frame.…

Functional Analysis · Mathematics 2024-08-09 K. Mahesh Krishna