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Related papers: Unconditional bases and Daugavet renormings

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The aim of this note is to provide several variants of the diameter two properties for Banach spaces. We study such properties looking for the abundance of diametral points, which holds in the setting of Banach spaces with the Daugavet…

Functional Analysis · Mathematics 2016-04-18 Julio Becerra Guerrero , Ginés López Pérez , Abraham Rueda Zoca

This paper studies Schauder frames in Banach spaces, a concept which is a natural generalization of frames in Hilbert spaces and Schauder bases in Banach spaces. The associated minimal and maximal spaces are introduced, as are shrinking and…

Functional Analysis · Mathematics 2009-10-20 Rui Liu

Inspired by R. Whitley's thickness index the last named author recently introduced the Daugavet index of thickness of Banach spaces. We continue the investigation of the behavior of this index and also consider two new versions of the…

Functional Analysis · Mathematics 2020-05-18 Rainis Haller , Johann Langemets , Vegard Lima , Rihhard Nadel , Abraham Rueda Zoca

We introduce the notion of a continuous Schauder frame for a Banach space. This is both a generalization of continuous frames and coherent states for Hilbert spaces and a generalization of unconditional Schauder frames for Banach spaces. As…

Functional Analysis · Mathematics 2018-12-21 Joseph Eisner , Daniel Freeman

We show that the duals of Banach algebras of scalar-valued bounded holomorphic functions on the open unit ball $B_E$ of a Banach space $E$ lack weak$^*$-strongly exposed points. Consequently, we obtain that some Banach algebras of…

Functional Analysis · Mathematics 2023-03-27 Mingu Jung

We show that if $x$ is a strongly extreme point of a bounded closed convex subset of a Banach space and the identity has a geometrically and topologically good enough local approximation at $x$, then $x$ is already a denting point. It turns…

Functional Analysis · Mathematics 2019-08-15 Trond A. Abrahamsen , Petr Hájek , Olav Nygaard , Stanimir Troyanski

Using methods of descriptive set theory, in particular, the determinacy of infinite games of perfect information, we answer several questions from the literature regarding different notions of bases in Banach spaces and lattices. For the…

Functional Analysis · Mathematics 2026-04-06 Antonio Avilés , Christian Rosendal , Mitchell A. Taylor , Pedro Tradacete

We study Daugavet points and $\Delta$-points in Lipschitz-free Banach spaces. We prove that, if $M$ is a compact metric space, then $\mu\in S_{\mathcal F(M)}$ is a Daugavet point if, and only if, there is no denting point of $B_{\mathcal…

Functional Analysis · Mathematics 2021-01-13 Mingu Jung , Abraham Rueda Zoca

Let $(\Omega, \mu)$, $(\Delta, \nu)$ be measure spaces and $p=1$ or $p=\infty$. Let $(\{f_\alpha\}_{\alpha\in \Omega}, \{\tau_\alpha\}_{\alpha\in \Omega})$ and $(\{g_\beta\}_{\beta\in \Delta}, \{\omega_\beta\}_{\beta\in \Delta})$ be…

Functional Analysis · Mathematics 2023-12-04 K. Mahesh Krishna

We show that all the symmetric projective tensor products of a Banach space $X$ have the Daugavet property provided $X$ has the Daugavet property and either $X$ is an $L_1$-predual (i.e.\ $X^*$ is isometric to an $L_1$-space) or $X$ is a…

Functional Analysis · Mathematics 2020-11-02 Miguel Martin , Abraham Rueda Zoca

We introduce an unconditional concept of almost squareness in order to provide a partial negative answer to the problem of existence of any dual almost square Banach space. We also take advantage of this notion to provide some criterion of…

Functional Analysis · Mathematics 2016-06-09 Luis García-Lirola , Abraham Rueda Zoca

We study the Daugavet property in tensor products of Banach spaces. We show that $L_1(\mu)\widehat{\otimes}_\varepsilon L_1(\nu)$ has the Daugavet property when $\mu$ and $\nu$ are purely non-atomic measures. Also, we show that…

Functional Analysis · Mathematics 2019-03-06 Abraham Rueda Zoca , Pedro Tradacete , Ignacio Villanueva

We extend the Daugavet property and a perfect version of it to transfinite cardinals in order to distinguish between spaces with the ordinary Daugavet property by some kind of complexity (topological, density\ldots), providing a number of…

Functional Analysis · Mathematics 2026-05-14 Antonio Avilés , Johann Langemets , Miguel Martín , Abraham Rueda Zoca

We develop tools to produce equivalent norms with specific local geometry around infinitely many points in the sphere of a Banach space via an inductive procedure. We combine this process with smoothness results and techniques to solve two…

Functional Analysis · Mathematics 2022-11-23 Andrés Quilis

In this note, we prove that the Daugavet property implies the polynomial Daugavet property, solving a longstanding open problem in the field. Our approach is based on showing that a geometric characterization of the Daugavet property due to…

Functional Analysis · Mathematics 2025-07-15 Sheldon Dantas , Miguel Martín , Yoël Perreau

We study random unconditional convergence for a basis in a Banach space. The connections between this notion and classical unconditionality are explored. In particular, we analyze duality relations, reflexivity, uniqueness of these bases…

Functional Analysis · Mathematics 2014-08-05 J. Lopez-Abad , P. Tradacete

We consider a certain type of geometric properties of Banach spaces, which includes for instance octahedrality, almost squareness, lushness and the Daugavet property. For this type of properties, we obtain a general reduction theorem,…

Functional Analysis · Mathematics 2017-11-27 Jan-David Hardtke

We investigate the existence of equivalent p-norms, 0< p 1, under which conditional symmetric or spreading bases in quasi-Banach spaces become isometric. For spreading bases (which need not be unconditional or even Schauder bases), we…

Functional Analysis · Mathematics 2026-01-23 José L. Ansorena , Alejandro Marcos

A Banach space $X$ has the Daugavet property if the Daugavet equation $\|\Id + T\|= 1 + \|T\|$ holds for every rank-one operator $T:X \longrightarrow X$. We show that the most natural attempts to introduce new properties by considering…

Functional Analysis · Mathematics 2008-11-26 Vladimir Kadets , Miguel Martin , Javier Meri

In this note, we study the geometry of the unit ball of the Banach space generated by the adequate family of all subsets of branches of the infinite binary tree, and answer several open questions related to slicely countably determined…

Functional Analysis · Mathematics 2026-03-16 Marcus Lõo , Yoël Perreau