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Related papers: Linear $L$-positive sets and their polar subspaces

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Using a strengthening of the concept of $\K$ set, introduced in this paper, we study a certain subclass of the class of $\K$ Banach spaces; the so called strongly $\K$ Banach spaces. This class of spaces includes subspaces of strongly…

Functional Analysis · Mathematics 2013-04-25 K. K. Kampoukos , S. K. Mercourakis

The Hahn-Banach theorem is an extension theorem for linear functionals which preserves certain properties. Specifically, if a linear functional is defined on a subspace of a real vector space which is dominated by a sublinear functional on…

Functional Analysis · Mathematics 2016-11-09 A. T. Diab , S. I. Nada , D. L. Fearnley

We study long chains of iterated weak* derived sets, that is sets of all weak* limits of bounded nets, of subspaces with the additional property that the penultimate weak* derived set is a proper norm dense subspace of the dual. We extend…

Functional Analysis · Mathematics 2024-08-05 Zdeněk Silber

Many of the known complemented subspaces of L_p have realizations as sequence spaces. In this paper a systematic approach to defining these spaces which uses partitions and weights is introduced. This approach gives a unified description of…

Functional Analysis · Mathematics 2007-05-23 Dale Alspach , Simei Tong

The notions of column and row operator space were extended by A. Lambert from Hilbert spaces to general Banach spaces. In this paper, we use column and row spaces over quotients of subspaces of general $L_p$-spaces to equip several Banach…

Functional Analysis · Mathematics 2008-11-23 Matthias Neufang , Volker Runde

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 and study the notion of overcomplete set in a Banach space, that subsumes and extends the classical concept of overcomplete sequence in a (separable) Banach space. We give existence and non-existence results of overcomplete…

Functional Analysis · Mathematics 2021-01-13 Tommaso Russo , Jacopo Somaglia

Targeting at sparse learning, we construct Banach spaces B of functions on an input space X with the properties that (1) B possesses an l1 norm in the sense that it is isometrically isomorphic to the Banach space of integrable functions on…

Machine Learning · Statistics 2015-01-16 Guohui Song , Haizhang Zhang , Fred J. Hickernell

In this work we provide a characterization of distinct type of (linear and non-linear) maps between Banach spaces in terms of the differentiability of certain class of Lipschitz functions. Our results are stated in an abstract bornological…

Functional Analysis · Mathematics 2021-10-04 Mohammed Bachir , Sebastián Tapia-García

A remarkable theorem of R. C. James is the following: suppose that $X$ is a Banach space and $C \subseteq X$ is a norm bounded, closed and convex set such that every linear functional $x^* \in X^*$ attains its supremum on $C$; then $C$ is a…

Functional Analysis · Mathematics 2016-09-06 Charles P. Stegall

A Banach space is {\it polynomially Schur} if sequential convergence against analytic polynomials implies norm convergence. Carne, Cole and Gamelin show that a space has this property and the Dunford-Pettis property if and only if it is…

Functional Analysis · Mathematics 2016-09-06 Jeff Farmer , William B. Johnson

This is the second of two closely related papers on transversality. Here we introduce the notion of strong tangential transversality of two closed subsets of a Banach space which is a natural sufficient condition for tangential…

Optimization and Control · Mathematics 2018-10-09 Mira Bivas , Mikhail Krastanov , Nadezhda Ribarska

We prove that $L_2(\mathbb{R})$ contains a Schauder basis of non-negative functions. Similarly, $L_p(\mathbb{R})$ contains a Schauder basic sequence of non-negative functions such that $L_p(\mathbb{R})$ embeds into the closed span of the…

Functional Analysis · Mathematics 2020-03-24 Daniel Freeman , Alexander M. Powell , Mitchell A. Taylor

A reflexive Banach space with an unconditional basis admits an equivalent $1$-unconditional $2R$ norm and embeds into a reflexive space with a $1$-symmetric $2R$ norm. Partial results on $1$-symmetric $2R$ renormings of spaces with a…

Functional Analysis · Mathematics 2024-08-19 Stephen Dilworth , Denka Kutzarova , Pavlos Motakis

Understanding the complemented subspaces of $L_p$ has been an interesting topic of research in Banach space theory since 1960. 1999, Alspach proposed a systematic approach to classifying the subspaces of $L_p$ by introducing a norm given by…

Functional Analysis · Mathematics 2015-03-17 Isaac DeFrain , Mitch Phillipson , Simei Tong

We collect several open questions in Banach spaces, mostly related to measure theoretic aspects of the theory. The problems are divided into five categories: miscellaneous problems in Banach spaces (non-separable $L^p$ spaces, compactness…

Functional Analysis · Mathematics 2016-07-27 Jose Rodriguez

Necessary and sufficient conditions for a separable Banach space to be a dual space are proved. Some applications are discussed

Functional Analysis · Mathematics 2010-03-12 Stefano Rossi

We introduce and study multivariate generalizations of the classical BV spaces of Jordan, F. Riesz and Wiener. The family of the introduced spaces contains or is intimately related to a considerable class of function spaces of modern…

Functional Analysis · Mathematics 2018-06-26 Alexander Brudnyi , Yuri Brudnyi

In Banach space theory, the ``local theory'' refers to the collection of finite dimensional methods and ideas which are used to study infinite dimensional spaces (see e.g. [P4,TJ]). It is natural to try to develop an analogous theory in the…

Functional Analysis · Mathematics 2009-09-25 Gilles Pisier

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