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Related papers: 2-local isometries on function spaces

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We develop tools for proving isomorphisms of normed spaces of Lipschitz functions over various doubling metric spaces and Banach spaces. In particular, we show that…

Functional Analysis · Mathematics 2019-10-18 Leandro Candido , Marek Cúth , Michal Doucha

We show that the existence of a strongly convex function with a Lipschitz derivative on a Banach space already implies that the space is isomorphic to a Hilbert space. Similarly, if both a function and its convex conjugate are $C^2$ then…

Functional Analysis · Mathematics 2025-06-11 Nicolas Borchard , Gerd Wachsmuth

Based on the characterization of surjective $L^p$-isometries of unitary groups in finite factors, we describe all surjective $L^p$-isometries between Grassmann spaces of projections with the same trace value in semifinite factors.

Operator Algebras · Mathematics 2021-04-16 Wenhua Qian , Junhao Shen , Weijuan Shi , Wenming Wu , Wei Yuan

In this article it is proved, that every locally compact second countable group has a left invariant metric d, which generates the topology on G, and which is proper, ie. every closed d-bounded set in G is compact. Moreover, we obtain the…

Operator Algebras · Mathematics 2007-05-23 Uffe Haagerup , Agata Przybyszewska

In the present paper 2-local derivations on various algebras of infinite dimensional matrix-valued functions on a compact are considered. It is proved that every 2-local derivation on such algebra is a derivation. Also we explain that the…

Operator Algebras · Mathematics 2015-09-21 Shavkat Ayupov , Farhodjon Arzikulov

We prove that every isometry between two combinatorial spaces is determined by a permutation of the canonical unit basis combined with a change of signs. As a consequence, we show that in the case of Schreier spaces, all the isometries are…

Functional Analysis · Mathematics 2019-11-15 C. Brech , V. Ferenczi , A. Tcaciuc

We prove that if $X$ is a real rearrangement-invariant function space on $[0,1]$, which is not isometrically isomorphic to $L_2,$ then every surjective isometry $T:X\to X$ is of the form $Tf(s)=a(s)f(\sigma(s))$ for a Borel function $a$ and…

Functional Analysis · Mathematics 2009-09-25 Nigel J. Kalton , Beata Randrianantoanina

In the present paper we prove that every 2-local inner derivation on the Lie ring of skew-symmetric matrices over a commutative ring is an inner derivation. We also apply our technique to various Lie algebras of infinite dimensional…

Rings and Algebras · Mathematics 2018-03-19 Shavkat Ayupov , Farhodjon Arzikulov

We prove that any isometry between the unit spheres of $C^2$-smooth (more generally, absolutely smooth) smooth Banach spaces extends to a linear isometry of the Banach spaces. This answers the famous Tingley's problem in the class of…

Functional Analysis · Mathematics 2021-11-01 Taras Banakh

We show in this paper that every bijective linear isometry between the continuous section spaces of two non-square Banach bundles gives rise to a Banach bundle isomorphism. This is to support our expectation that the geometric structure of…

Functional Analysis · Mathematics 2014-02-27 Ming-Hsiu Hsu , Ngai-Ching Wong

We show that every metric space with bounded geometry uniformly embeds into an explicit reflexive Banach space (a direct sum of l^p spaces). In the case of discrete groups we show the analogue of a-T-menability. That is, we construct a…

Operator Algebras · Mathematics 2016-09-07 Nathanial Brown , Erik Guentner

The paper is devoted to 2-local automorphisms on $AW^\ast$-algebras. Using the technique of matrix algebras over a unital Banach algebra we prove that any 2-local automorphism on an arbitrary $AW^\ast$-algebra without finite type~I direct…

Operator Algebras · Mathematics 2019-09-16 Shavkat Ayupov , Karimbergen Kudaybergenov , Turabay Kalandarov

We study the group of surjective linear isometries on certain real Banach sequence spaces using the preservation of extreme points in the closed unit ball. Our main result provides a characterization of the extreme points of the dual unit…

Functional Analysis · Mathematics 2025-08-20 Christina Brech , Victor dos Santos Ronchim

Let $X$ be a (real or complex) rearrangement-in\-va\-riant function space on $\Om$ (where $\Om = [0,1]$ or $\Om \subseteq \bbN$) whose norm is not proportional to the $L_2$-norm. Let $H$ be a separable Hilbert space. We characterize…

Functional Analysis · Mathematics 2016-09-06 Beata Randrianantoanina

For a locally compact Hausdorff space $L$, we denote by $C_0(L,\mathbb{R})$ the Banach space of all continuous real-valued functions on $L$ vanishing at infinity, endowed with the supremum norm. In this paper, we prove that every surjective…

Functional Analysis · Mathematics 2026-03-03 Yuta Enami , Izuho Matsuzaki

We solve two main questions on linear structures of (non-)norm-attaining Lipschitz functions. First, we show that for every infinite metric space $M$, the set consisting of Lipschitz functions on $M$ which do not strongly attain their norm…

Functional Analysis · Mathematics 2024-04-12 Geunsu Choi , Mingu Jung , Han Ju Lee , Oscar Roldan

We prove that if the group of isometries of C(X,E) is algebraically reflexive, then the group of n-isometries is also algebraically reflexive. Here, X is a compact Hausdorff space and E is a Banach space. As a corollary to this, we…

Functional Analysis · Mathematics 2012-05-28 A. B. Abubaker

We consider abstract Banach spaces of analytic functions on general bounded domains that satisfy only a minimum number of axioms. We describe all invertible (equivalently, surjective) weighted composition operators acting on such spaces.…

Functional Analysis · Mathematics 2022-08-23 Alejandro Mas , Dragan Vukotić

Certain previously known upper bounds on the moments of the norm of martingales in 2-smooth Banach spaces are improved. Some of these improvements hold even for sums of independent real-valued random variables. Applications to concentration…

Probability · Mathematics 2017-01-17 Iosif Pinelis

In the present paper we introduce and investigate the notion of 2-local linear map on vector spaces. A sufficient condition is obtained for linearity of a 2-local linear map on finite dimensional vector spaces. Based on this result we prove…

Rings and Algebras · Mathematics 2020-09-24 Shavkat Ayupov , Farhodjon Arzikulov , Nodirbek Umrzaqov , Olimjon Nuriddinov