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We characterize the finite dimensional asymmetric normed spaces which are right bounded and the relation of this property with the natural compactness properties of the unit ball, as compactness and strong compactness. In contrast with some…

General Topology · Mathematics 2017-02-15 Natalia Jonard-Pérez , Enrique A. Sánchez-Pérez

We show that the space of continuous functions over a compact space X admits an equivalent pointwise-lowersemicontinuous locally uniformly rotund norm whenever X admits a fully closed map onto a compact Y such that C(Y) and the spaces of…

Functional Analysis · Mathematics 2023-12-27 Todor Manev

We study Banach spaces induced by families of finite sets in the most natural (Schreier-like) way, that is, we consider the completion $X_\mc{F}$ of $c_{00}$ with respect to the norm $\sup\{\sum_{k\in F}|x(k)|:F\in\mc{F}\}$ where $\mc{F}$…

Functional Analysis · Mathematics 2024-04-03 Piotr Borodulin-Nadzieja , Barnabás Farkas , Sebastian Jachimek , Anna Pelczar-Barwacz

It is well known that if the nonempty player of the Banach-Mazur game has a winning strategy on a space, then that space is Baire in all powers even in the box topology. The converse of this implication may be true also: We know of no…

Logic · Mathematics 2014-10-28 Fred Galvin , Marion Scheepers

A ringed finite space is a ringed space whose underlying topological space is finite. The category of ringed finite spaces contains, fully faithfully, the category of finite topological spaces and the category of affine schemes. Any ringed…

Algebraic Geometry · Mathematics 2014-10-13 Fernando Sancho de Salas

The hereditary property of convexity and starlikeness for conformal mappings does not generalize to univalent harmonic mappings. This failure leads us to the notion of fully starlike and convex mappings of order \alpha, (0\leq \alpha<1). A…

Complex Variables · Mathematics 2012-07-18 Sumit Nagpal , V. Ravichandran

A space is called Dieudonn\'{e} complete if it is complete relative to the maximal uniform structure compatible with its topology. In this paper, we investigated when the function space $C(X,Y)$ of all continuous functions from a…

General Topology · Mathematics 2024-09-04 Mikhail Al'perin , Alexander V. Osipov

A subbundle of variable dimension inside the tangent bundle of a smooth manifold is called a smooth distribution if it is the pointwise span of a family of smooth vector fields. We prove that all such distributions are finitely generated,…

Differential Geometry · Mathematics 2021-01-28 Lance D. Drager , Jeffrey M. Lee , Efton Park , Ken Richardson

Several recent papers investigated unbounded convergences in Banach lattices. Combine all unbounded convergences, including unbounded order (norm, absolute weak, absolute weak*) convergence, we characterize L-weakly compact sets, L-weakly…

Functional Analysis · Mathematics 2021-04-06 Zhangjun Wang , Zili Chen , Jinxi Chen

We establish a general criterion for the existence of convex sets of fixed shape as, e.g., balls of a given radius, of maximal probability on Banach spaces. We also provide counterexamples showing that their existence my fail even in some…

Functional Analysis · Mathematics 2023-09-07 Bernd Schmidt

We construct a Banach space $X$ for which the set of norm-attaining functionals $NA(X,\mathbb{R})$ does not contain any non-trivial cone. Even more, given two linearly independent norm-attaining functionals on $X$, no other element of the…

Functional Analysis · Mathematics 2025-01-08 Miguel Martin

We give a new scale of completeness conditions for exponential systems in two types of functional spaces on subsets of the complex plane. The first is the Banach spaces of functions that are continuous on a compact and simultaneously…

Complex Variables · Mathematics 2023-04-05 B. N. Khabibullin , E. G. Kudasheva , R. R. Muryasov

We investigate products of sets of reals with combinatorial covering properties. A topological space satisfies $\mathsf{S}_1(\Gamma,\Gamma)$ if for each sequence of point-cofinite open covers of the space, one can pick one element from each…

General Topology · Mathematics 2019-12-06 Piotr Szewczak , Magdalena Włudecka

A topological space $X$ is called a topological fractal if $X=\bigcup_{f\in\mathcal F}f(X)$ for a finite system $\mathcal F$ of continuous self-maps of $X$, which is topologically contracting in the sense that for every open cover $\mathcal…

General Topology · Mathematics 2016-02-23 Taras Banakh , Magdalena Nowak , Filip Strobin

Many of the known complemented subspaces of L_p have realizations as sequence spaces. In this paper a systematic approach to defining these spaces which uses partitions and weights is introduced. This approach gives a unified description of…

Functional Analysis · Mathematics 2007-05-23 Dale Alspach , Simei Tong

In this paper, we approach the question if some of the separation axioms are equivalent in the class of asymmetric normed spaces. In particular, we make a remark on a known theorem which states that every $T_1$ asymmetric normed space with…

General Topology · Mathematics 2019-05-10 Victor Donjuán , Natalia Jonard-Pérez

A finite or infinite matrix $A$ is image partition regular provided that whenever $\mathbb{N}$ is finitely colored, there must be some $\overset{\rightarrow}{x}$ with entries from $\mathbb{N}$ such that all entries of $A…

Combinatorics · Mathematics 2018-04-04 Sukrit Chakraborty , Sourav Kanti Patra

A net $(x_\alpha)$ in a Banach lattice $X$ is said to un-converge to a vector $x$ if $\bigl\lVert\lvert x_\alpha-x\rvert\wedge u\bigr\rVert\to 0$ for every $u\in X_+$. In this paper, we investigate un-topology, i.e., the topology that…

Functional Analysis · Mathematics 2017-01-24 M. Kandić , M. A. A. Marabeh , V. G. Troitsky

We say that a smooth normed space $X$ has a property (SL), if every mapping $f:X \to X$ preserving the semi-inner product on $X$ is linear. It is well known that every Hilbert space has the property (SL) and the same is true for every…

Functional Analysis · Mathematics 2022-04-14 Tomasz Kobos , Paweł Wójcik

A family is constructed of cardinality equal to the continuum, whose members are totally incomparable, reflexive, hereditarily indecomposable Banach spaces.

Functional Analysis · Mathematics 2007-05-23 Ioannis Gasparis