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Related papers: Some results on almost square Banach spaces

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We consider a Banach space, which comes naturally from c0 and it appears in the literature, and we prove that this space has the fixed point property for non-expansive mappings.

Functional Analysis · Mathematics 2012-11-15 Costas Poulios

A natural class of ideals, almost isometric ideals, of Banach spaces is defined and studied. The motivation for working with this class of subspaces is our observation that they inherit diameter 2 properties and the Daugavet property.…

Functional Analysis · Mathematics 2013-06-21 Trond A. Abrahamsen , Vegard Lima , Olav Nygaard

The class J of simultaneously almost transitive, uniformly convex and uniformly smooth Banach spaces is characterized in terms of convex-transitivity and weak geometry of the norm.

Functional Analysis · Mathematics 2008-04-10 Jarno Talponen

We show that every Banach space containing isomorphic copies of $c_0$ can be equivalently renormed so that every nonempty relatively weakly open subset of its unit ball has diameter 2 and, however, its unit ball still contains convex…

Functional Analysis · Mathematics 2014-10-17 Julio Becerra Guerrero , Ginés López-Pérez , Abraham Rueda Zoca

For $C^{*}$-algebras $A$ and $B$, the operator space projective tensor product $A\hat{\otimes}B$ and the Banach space projective tensor product $A\otimes_{\gamma}B$ are shown to be symmetric. We also show that $A\hat{\otimes}B$ is weakly…

Operator Algebras · Mathematics 2012-05-09 Ajay Kumar , Vandana Rajpal

We prove that a Tychonoff space $X$ is an Ascoli space (resp., a sequentially Ascoli space) if and only if for each Banach space $E$, every $k$-continuous and almost $k$-compact (resp., almost $k$-sequential) map $T$ form $X$ into the…

Functional Analysis · Mathematics 2023-07-24 Saak Gabriyelyan

We show that the classes of separable reflexive Banach spaces and of spaces with separable dual are strongly bounded. This gives a new proof of a recent result of E. Odell and Th. Schlumprecht, asserting that there exists a separable…

Functional Analysis · Mathematics 2007-05-23 Pandelis Dodos , Valentin Ferenczi

The new concepts are introduced of almost overcomplete sequence in a Banach space and almost overtotal sequence in a dual space. We prove that any of such sequences is relatively norm-compact and we obtain several applications of this fact.

Functional Analysis · Mathematics 2014-06-26 Vladimir P. Fonf , Clemente Zanco

Let $X$ be a Banach space. We prove that, for a large class of Banach or quasi-Banach spaces $E$ of $X$-valued sequences, the sets $E-\bigcup _{q\in\Gamma}\ell_{q}(X)$, where $\Gamma$ is any subset of $(0,\infty]$, and $E-c_{0}(X)$ contain…

Functional Analysis · Mathematics 2012-08-30 G. Botelho , D. Diniz , V. V. Favaro , D. Pellegrino

In this paper we study conditions on a Banach space X that ensure that the Banach algebra K(X) of compact operators is amenable. We give a symmetrized approximation property of X which is proved to be such a condition. This property is…

Functional Analysis · Mathematics 2008-02-03 Niels Gronbaek , Barry E. Johnson , George A. Willis

We discuss the geometry of Banach spaces whose norm is octahedral or, more generally, locally or weakly octahedral. Our main results characterize these spaces in terms of covering of the unit ball.

Functional Analysis · Mathematics 2014-10-15 Rainis Haller , Johann Langemets

Non-commutative $L^p$-spaces are shown to constitute examples of a class of Banach quasi *-algebras called CQ*-algebras. For $p\geq 2$ they are also proved to possess a {\em sufficient} family of bounded positive sesquilinear forms…

Mathematical Physics · Physics 2009-04-01 F. Bagarello , C. Trapani , S. Triolo

We prove that the diametral strong diameter 2 property of a Banach space (meaning that, in convex combinations of relatively weakly open subsets of its unit ball, every point has an "almost diametral" point) is stable under 1-sums, i.e.,…

Functional Analysis · Mathematics 2016-03-29 Rainis Haller , Katriin Pirk , Märt Põldvere

Necessary and sufficient conditions for Banach space to be(isometrically isomorphic to) a dual space will be given.

Functional Analysis · Mathematics 2010-03-12 Stefano Rossi

Following [3] we say that a Tychonoff space $X$ is an Ascoli space if every compact subset $\mathcal{K}$ of $C_k(X)$ is evenly continuous; this notion is closely related to the classical Ascoli theorem. Every $k_\mathbb{R}$-space, hence any…

Functional Analysis · Mathematics 2015-04-17 S. Gabriyelyan , J. Kakol , G. Plebanek

We study the relation between the linear stability of almost-symmetries and the geometry of the Banach spaces on which these transformations are defined. We show that any transformation between finite dimensional Banach spaces that…

Mathematical Physics · Physics 2019-07-15 Javier Cuesta

We present a construction that enables one to find Banach spaces $X$ whose sets $NA(X)$ of norm attaining functionals do not contain two-dimensional subspaces and such that, consequently, $X$ does not contain proximinal subspaces of finite…

Functional Analysis · Mathematics 2019-02-05 Vladimir Kadets , Gines Lopez Perez , Miguel Martin , Dirk Werner

In this paper, we study the coarse Lipschitz geometry of Banach spaces with several asymptotic properties. Specifically, we look at asymptotically uniformly smoothness and convexity, and several distinct Banach-Saks-like properties. Among…

Functional Analysis · Mathematics 2017-02-17 Bruno de Mendonça Braga

It is proved that the relation of isomorphism between separable Banach spaces is a complete analytic equivalence relation, i.e., that any analytic equivalence relation Borel reduces to it. Thus, separable Banach spaces up to isomorphism…

Functional Analysis · Mathematics 2014-02-26 Valentin Ferenczi , Alain Louveau , Christian Rosendal

A recent result of T.~Abrahamsen, P.~H\'ajek and S.~Troyanski states that a separable Banach space is almost square if and only if there exists $h\in S_{X^{****}}$ such that $\|x+h\|=\max\{\|x\|,1\}$ for all $x\in X$. The proof passes…

Functional Analysis · Mathematics 2021-10-28 Antonio Avilés , Gonzalo Martínez-Cervantes , Abraham Rueda Zoca