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Related papers: Norm-attaining tensors and nuclear operators

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We obtain a complete characterization of the norm attainment set of a bounded linear functional on a normed space, in terms of a semi-inner-product defined on the space. Motivated by this result, we further apply the concept of…

Functional Analysis · Mathematics 2018-03-19 Debmalya Sain

We study the set $\operatorname{SNA}(M,Y)$ of those Lipschitz maps from a (complete pointed) metric space $M$ to a Banach space $Y$ which (strongly) attain their Lipschitz norm (i.e.\ the supremum defining the Lipschitz norm is a maximum).…

Functional Analysis · Mathematics 2019-01-09 Bernardo Cascales , Rafa Chiclana , Luis Garcia-Lirola , Miguel Martin , Abraham Rueda Zoca

The main result of the paper shows that, for 1<p and 1<=q, a linear operator T from l_p to l_q attains its norm if, and only if, there exists a not weakly null maximizing sequence for T (counterexamples can be easily constructed when p=1).…

Functional Analysis · Mathematics 2015-10-02 Daniel Pellegrino , Eduardo V. Teixeira

Suppose $X$ and $Y$ are Banach spaces, and ${\mathcal{I}}$, ${\mathcal{J}}$ are operator ideals (for instance, the ideals of strictly singular, weakly compact, or compact operators). Under what conditions does the inclusion…

Operator Algebras · Mathematics 2013-09-24 T. Oikhberg , E. Spinu

We show that there exist infinite-dimensional extremely non-complex Banach spaces, i.e. spaces $X$ such that the norm equality $\|Id + T^2\|=1 + \|T^2\|$ holds for every bounded linear operator $T:X\longrightarrow X$. This answers in the…

Functional Analysis · Mathematics 2008-11-26 Piotr Koszmider , Miguel Martin , Javier Meri

In this paper, we study the (uniform) strong subdifferentiability of the norms of the Banach spaces $\mathcal{P}(^N X, Y^*)$, $X \hat{\otimes}_\pi \cdots \hat{\otimes}_\pi X$ and $\hat{\otimes}_{\pi_s,N} X$. Among other results, we…

Functional Analysis · Mathematics 2022-09-07 Sheldon Dantas , Mingu Jung , Martin Mazzitelli , Jorge Tomás Rodríguez

Let $X, Y$ be infinite dimensional, Banach spaces. Let $\mathcal{L}(X, Y)$ be the space of bounded operators . Motivated by the fact that smoothness of norm in the higher duals of even order of a Banach space can lead to Frechet…

Functional Analysis · Mathematics 2022-12-13 Taduri Srinivasa Siva Rama Krishna Rao

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

According to Kim, Peris and Song, a continuous linear operator $T$ on a complex Banach space $X$ is called {\it numerically hypercyclic} if the numerical orbit $\{f(T^nx):n\in\N\}$ is dense in $\C$ for some $x\in X$ and $f\in X^*$…

Functional Analysis · Mathematics 2013-02-12 Stanislav Shkarin

Projective Norms are a class of tensor norms that map on the input and output spaces. These norms are useful for providing a measure of entanglement. Calculating the projective norms is an NP-hard problem, which creates challenges in…

Quantum Physics · Physics 2026-01-05 Aaditya Rudra , Maria Anastasia Jivulescu

In this paper we provide necessary and sufficient conditions for the existence of non-norm-attaining operators in $\mathcal{L}(E, F)$. By using a theorem due to Pfitzner on James boundaries, we show that if there exists a relatively compact…

Functional Analysis · Mathematics 2021-02-15 Sheldon Dantas , Mingu Jung , Gonzalo Martínez-Cervantes

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

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

The concept of uniform convexity of a Banach space was generalized to linear operators between Banach spaces and studied by Beauzamy [1976]. Under this generalization, a Banach space X is uniformly convex if and only if its identity map I_X…

Functional Analysis · Mathematics 2007-05-23 J Wenzel

Let $\mathbb{X}$ be a Banach space and let $\mathbb{X}^*$ be the dual space of $\mathbb{X}.$ For $x,y \in \mathbb{X},$ $ x$ is said to be $T$-orthogonal to $y$ if $Tx(y) =0,$ where $T$ is a bounded linear operator from $\mathbb{X}$ to…

Functional Analysis · Mathematics 2024-08-14 Debmalya Sain , Souvik Ghosh , Kallol Paul

We introduce a new norm, called $N^{p}$-norm $(1\leq{p}<\infty)$ on a space $N^{p}(V,W)$ where $V$ and $W$ are abstract operator spaces. By proving some fundamental properties of the space $N^{p}(V,W)$, we also obtain that if $W$ is…

Operator Algebras · Mathematics 2007-05-23 Yun-Su Kim

It has been very recently discovered that there are compact linear operators between Banach spaces which cannot be approximated by norm attaining operators. The aim of this expository paper is to give an overview of those examples and also…

Functional Analysis · Mathematics 2017-04-25 Miguel Martin

In this short note, we prove that the set of elementary tensors is weakly closed in the projective tensor product of two Banach spaces. As a result, we are able to answer a question from the literature proving that if $(x_n) \subset X$ and…

Functional Analysis · Mathematics 2025-03-19 Colin Petitjean

We extend the $\lambda$-theory of operator spaces given by Defant and Wiesner (2014), that generalizes the notion of the projective, Haagerup and Schur tensor norm for operator spaces to matrix ordered spaces and Banach $*$-algebras. Given…

Operator Algebras · Mathematics 2017-10-11 Preeti Luthra , Ajay Kumar , Vandana Rajpal

We observe that the classical notion of numerical radius gives rise to a notion of smoothness in the space of bounded linear operators on certain Banach spaces, whenever the numerical radius is a norm. We demonstrate an important class of…

Functional Analysis · Mathematics 2021-07-09 Saikat Roy , Debmalya Sain
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