English
Related papers

Related papers: Uniformly convex-transitive function spaces

200 papers

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

The convex-transitivity property can be seen as a convex generalization of the almost transitive (or quasi-isotropic) group action of the isometry group of a Banach space on its unit sphere. We will show that certain Banach algebras,…

Operator Algebras · Mathematics 2015-01-23 María J. Martín , Jarno Talponen

If X is a convex-transitive Banach space and 1\leq p\leq \infty then the closed linear span of the simple functions in the Bochner space L^{p}([0,1],X) is convex-transitive. If H is an infinite-dimensional Hilbert space and C_{0}(L) is…

Functional Analysis · Mathematics 2008-01-28 Jarno Talponen

In this paper Hilbert spaces are characterized among Banach spaces in terms of transitivity with respect to nicely behaved subgroups of the isometry group. For example, the following result is typical here: If X is a real Banach space…

Functional Analysis · Mathematics 2008-09-11 Jarno Talponen

We investigate a method for producing concrete convex-transitive Banach spaces. The gist of the method is in getting rid of dissymmetries of a given space by taking a carefully chosen quotient. The spaces of interest here are typically…

Functional Analysis · Mathematics 2011-06-08 Jarno Talponen

We provide a few characterizations of a strictly convex Banach space. Using this we improve the main theorem of [Digar, Abhik; Kosuru, G. Sankara Raju; Cyclic uniform Lipschitzian mappings and proximal uniform normal structure. Ann. Funct.…

Functional Analysis · Mathematics 2023-09-12 Abhik Digar , G. Sankara Raju Kosuru

It is shown that a Banach space with locally uniformly convex dual admits an equivalent norm which is itself locally uniformly convex. It follows that on any such space all continuous real-valued functions may be uniformly approximated by…

Functional Analysis · Mathematics 2007-05-23 Richard Haydon

In this paper the theory of uniformly convex metric spaces is developed. These spaces exhibit a generalized convexity of the metric from a fixed point. Using a (nearly) uniform convexity property a simple proof of reflexivity is presented…

Metric Geometry · Mathematics 2016-04-08 Martin Kell

We investigate several boundedness properties of function spaces considered as uniform spaces.

General Topology · Mathematics 2018-02-19 Lubica Hola , Ljubisa D. R. Kocinac

In this paper we investigate real convex-transitive Banach spaces X, which admit a 1-dimensional bicontractive projection P on X. Various mild conditions regarding the weak topology and the geometry of the norm are provided, which guarantee…

Functional Analysis · Mathematics 2007-05-23 Jarno Talponen

We study Banach spaces whose group of isometries acts micro-transitively on the unit sphere. We introduce a weaker property, which one-complemented subspaces inherit, that we call uniform micro-semitransitivity. We prove a number of results…

Functional Analysis · Mathematics 2019-06-25 Félix Cabello Sánchez , Sheldon Dantas , Vladimir Kadets , Sun Kwang Kim , Han Ju Lee , Miguel Martín

We present and study some transfinite versions of (almost isometric) ideals in Banach spaces. As these notions are closely related with Lindenstrauss and Gurari\u{\i} spaces respectively, we will present a similar characterization for…

Functional Analysis · Mathematics 2025-05-08 Esteban Martínez Vañó , Abraham Rueda Zoca

The duality of uniform approximation property for Banach spaces is well known. In this note, we establish, under the assumption of local reflexivity, the duality of uniform approximation property in the category of operator spaces.

Operator Algebras · Mathematics 2014-10-28 Yanqi Qiu

We introduce a flexible almost isometric version of the almost transitivity property of Banach spaces. With the help of this new notion we generalize to several directions a strong recent rotational characterization of Hilbert spaces due to…

Functional Analysis · Mathematics 2007-05-23 J. Talponen

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

This paper addresses the study and characterizations of variational convexity of extended-real-valued functions on Banach spaces. This notion has been recently introduced by Rockafellar, and its importance has been already realized and…

Optimization and Control · Mathematics 2023-08-29 Pham Duy Khanh , Vu Vinh Huy Khoa , Boris S. Mordukhovich , Vo Thanh Phat

In this paper we give some results about the approximation of a Lipschitz function on a Banach space by means of $\Delta$-convex functions. In particular, we prove that the density of $\Delta$-convex functions in the set of Lipschitz…

Functional Analysis · Mathematics 2009-09-25 Manuel Cepedello Boiso

We single out and study a natural class of Banach spaces -- almost square Banach spaces. In an almost square space we can find, given a finite set $x_1,x_2,\ldots,x_N$ in the unit sphere, a unit vector $y$ such that $\|x_i-y\|$ is almost…

Functional Analysis · Mathematics 2015-08-25 Trond A. Abrahamsen , Johann Langemets , Vegard Lima

We prove that the following three properties for a Banach space are all different from each other: every finite convex combination of slices of the unit ball is (1) relatively weakly open, (2) has nonempty interior in relative weak topology…

Functional Analysis · Mathematics 2017-03-10 Rainis Haller , Paavo Kuuseok , Märt Põldvere

Another proof that uniformly nonsquare Banach spaces have the fixed point property is presented.

Functional Analysis · Mathematics 2024-04-10 Tim Dalby
‹ Prev 1 2 3 10 Next ›