English
Related papers

Related papers: Nonlinear aspects of super weakly compact sets

200 papers

Motivated by the equivalent definition of a continuous operator between Banach spaces in terms of weakly null nets, we introduce unbounded continuous operators by replacing weak convergence with the unbounded absolutely weak convergence (…

Functional Analysis · Mathematics 2020-08-11 Omid Zabeti

We list a number of problems in several topics related to compactness in nonseparable Banach spaces. Namely, about the Hilbertian ball in its weak topology, spaces of continuous functions on Eberlein compacta, WCG Banach spaces, Valdivia…

Functional Analysis · Mathematics 2010-11-08 Antonio Avilés , Ondřej F. K. Kalenda

The Banach space $E$ has the weakly compact approximation property (W.A.P. for short) if there is a constant $C < \infty$ so that for any weakly compact set $D \subset E$ and $\epsilon > 0$ there is a weakly compact operator $V: E \to E$…

Functional Analysis · Mathematics 2007-05-23 Edward Odell , Hans-Olav Tylli

In this paper we study different aspects of the representation of weak*-compact convex sets of the bidual $X^{**}$ of a separable Banach space $X$ via a nested sequence of closed convex bounded sets of $X$.

Functional Analysis · Mathematics 2014-06-27 Jesús M. F. Castillo , Manuel González , Pier Luigi Papini

Let X be a Banach space. Given a subset A of the dual space X* denote by $A_{(1)}$ the weak* sequential closure of A, i.e., the set of all limits of weak*-convergent sequences in A. The study of weak* sequential closures of linear subspaces…

Functional Analysis · Mathematics 2007-05-23 M. I. Ostrovskii

In this article we extend the notion of orthogonal metric space to weak orthogonal metric space. Then we establish fixed point results for a mapping satisfying a more general contraction condition. Several nontrivial examples are given in…

Functional Analysis · Mathematics 2018-06-27 Tanusri Senapati

It is shown that if $C$ is a nonempty convex and weakly compact subset of a Banach space $X$ with $M(X)>1$ and $T:C\rightarrow C$ satisfies condition $(C)$ or is continuous and satisfies condition $(C_{\lambda})$ for some $\lambda \in…

Functional Analysis · Mathematics 2015-11-24 Anna Betiuk-Pilarska , Andrzej Wiśnicki

In continuation of the paper [3], we discuss various consequences of Hahn-Banach theorem for bounded b-linear functional in linear n-normed space and describe the notion of reflexivity of linear n-normed space with respect to bounded…

Functional Analysis · Mathematics 2024-10-29 Prasenjit Ghosh , Tapas Kumar Samanta

Lecture notes on Weak Topologies: We discuss about the weak and weak star topologies on a normed linear space. Our aim is to prove the well known Banach-Alaouglu theorem and discuss some of its consequences, in particular, characterizations…

Functional Analysis · Mathematics 2020-10-06 G. Ramesh

A Banach space X is superreflexive if each Banach space Y that is finitely representable in X is reflexive. Superreflexivity is known to be equivalent to J-convexity and to the non-existence of uniformly bounded factorizations of the…

Functional Analysis · Mathematics 2016-09-07 Joerg Wenzel

A strong submeasure on a compact metric space X is a sub-linear and bounded operator on the space of continuous functions on X. A strong submeasure is positive if it is non-decreasing. By Hahn-Banach theorem, a positive strong submeasure is…

Dynamical Systems · Mathematics 2019-01-11 Tuyen Trung Truong

In a series of previous papers, we initiated a systematic study of semihypergroups and had a thorough discussion on certain analytic and algebraic aspects associated to this class of objects. In particular, we introduced the notion of…

Functional Analysis · Mathematics 2024-04-30 Choiti Bandyopadhyay

We characrterize extreme contractions defined between \ finite-dimensional polyhedral Banach spaces using $k$- smoothness of operators. We also explore weak L-P property, a recently introduced concept in the study of extreme contractions.…

Functional Analysis · Mathematics 2024-08-14 Arpita Mal , Kallol Paul , Subhrajit Dey

Fixed point theory studies conditions under which nonexpansive maps on Banach spaces have fixed points. This paper examines the open question of whether every reflexive Banach space has the fixed point property. After surveying classical…

Functional Analysis · Mathematics 2025-09-17 Faruk Alpay , Hamdi Alakkad

Reflexive cones in Banach spaces are cones with weakly compact intersection with the unit ball. In this paper we study the structure of this class of cones. We investigate the relations between the notion of reflexive cones and the…

Functional Analysis · Mathematics 2012-05-29 Emanuele Casini , Enrico Miglierina , Ioannis A. Polyrakis , Foivos Xanthos

We initiate a study of cohomological aspects of weakly almost periodic group representations on Banach spaces, in particular, isometric representations on reflexive Banach spaces. Using the Ryll-Nardzewski fixed point Theorem, we prove a…

Group Theory · Mathematics 2013-02-12 Uri Bader , Christian Rosendal , Roman Sauer

A topological space is said to be sequential if every sequentially closed subspace is closed. We consider Banach spaces with weak*-sequential dual ball. In particular, we show that if $X$ is a Banach space with weak*-sequentially compact…

Functional Analysis · Mathematics 2016-12-20 Gonzalo Martínez-Cervantes

We obtain some results for and further examples of subprojective and superprojective Banach spaces. We also give several conditions providing examples of non-reflexive superprojective spaces; one of these conditions is stable under…

Functional Analysis · Mathematics 2016-06-03 Elói M. Galego , Manuel González , Javier Pello

The concept of a profile decomposition formalizes concentration compactness arguments on the functional-analytic level, providing a powerful refinement of the Banach-Alaoglu weak-star compactness theorem. We prove existence of profile…

Functional Analysis · Mathematics 2015-02-03 Sergio Solimini , Cyril Tintarev

In this paper, we show that the sum of a compact convex subset and a simultaneously $\tau$-strongly proximinal convex subset (resp. simultaneously approximatively $\tau$-compact convex subset) of a Banach space X is simultaneously…

Functional Analysis · Mathematics 2020-02-28 Longfa Sun , Yuqi Sun , Wen Zhang , Zheming Zheng