English
Related papers

Related papers: On control measures of multimeasures

200 papers

We introduce the notion of a positive spectral measure on a $\sigma$-algebra, taking values in the positive projections on a Banach lattice. Such a measure generates a bounded positive representation of the bounded measurable functions. If…

Functional Analysis · Mathematics 2016-10-19 Marcel de Jeu , Frejanne Ruoff

For a Banach D-bimodule M over an abelian unital C*-algebra D, we define E(M) as the collection of norm-one eigenvectors for the dual action of D on the Banach space dual of M. Equip E(M) with the weak-* topology. We develop general…

Operator Algebras · Mathematics 2007-05-23 Allan P. Donsig , David R. Pitts

Banach algebra A for which the natural embedding x into x^ of A into WAP(A)* is bounded below; that is, for some m in R with m > 0 we have ||x^|| > m ||x||, is called a WAP-algebra. Through we mainly concern with weighted measure algebra…

Functional Analysis · Mathematics 2015-01-27 H. R. Ebrahimi Vishki , B. Khodsiani , A. Rejali

Let $X$ be a Banach space, let $(\Omega,\mu)$ be a $\sigma$-finite measure space and let $A,B\colon\Omega\to B(X)$ be strongly measurable $\gamma$-bounded functions. We show that for all $x\in X$ and all $x^*\in X^*$, there exist a Hilbert…

Functional Analysis · Mathematics 2024-02-19 Christian Le Merdy

It is proved that for an h-homogeneous space X the following conditions are equivalent: 1) X is a densely homogeneous space with a dense complete subspace; 2) X is $\sigma$-discretely controlled.

General Topology · Mathematics 2016-01-18 Sergey Medvedev

Let $X$ and $Y$ be Banach spaces such that the ideal of operators which factor through $Y$ has codimension one in the Banach algebra $\mathscr{B}(X)$ of all bounded operators on $X$, and suppose that $Y$ contains a complemented subspace…

K-Theory and Homology · Mathematics 2015-04-06 Tomasz Kania , Piotr Koszmider , Niels Jakob Laustsen

Let $M^{n}$, $n\in\{3,4,5\}$, be a closed aspherical $n$-manifold and $S\subset M$ a subset consisting of disjoint incompressible embedded closed aspherical submanifolds (possibly with different dimensions). When $n =3,4$, we show that…

Differential Geometry · Mathematics 2025-12-19 Shuli Chen , Jianchun Chu , Jintian Zhu

Let $\nu$ be a vector measure defined on a $\sigma$-algebra $\Sigma$ and taking values in a Banach space. We prove that if $\nu$ is homogeneous and $L_1(\nu)$ is non-separable, then there is a vector measure $\tilde{\nu}:\Sigma \to…

Functional Analysis · Mathematics 2024-04-09 José Rodríguez

We obtain two partial answers to the 3-space problem for isomorphic polyhedrality: (1) every twisted sum of $C(\alpha)$, $\alpha<\omega_1$, with a separable isomorphically polyhedral space with the BAP, is isomorphically polyhedral. (2)…

Functional Analysis · Mathematics 2025-03-12 Jesús M. F. Castillo , Alberto Salguero Alarcón

In each manifold $M$ modeled on a finite or infinite dimensional cube $[0,1]^n$ we construct a meager $F_\sigma$-subset $X\subset M$ which is universal meager in the sense that for each meager subset $A\subset M$ there is a homeomorphism…

Geometric Topology · Mathematics 2013-05-28 Taras Banakh , Dusan Repovs

The purpose of this note is to describe some algebraic conditions on a Banach algebra which force it to be finite dimensional. One of the main results in Theorem~2 which states that for a locally compact group $G$, $G$ is compact if there…

Functional Analysis · Mathematics 2007-05-23 Ali Ghaffari , Ali Reza Medghalchi

A long-standing question in the theory of measures of noncompactness is that for the Kuratowski measure of noncompactness $\alpha$ defined on a metric space $M$, and for every bounded subset $B\subset M$, is there a countable subset…

Functional Analysis · Mathematics 2021-01-28 Xiaoling Chen , Lixin Cheng

We study the controlled dynamics of the {\it ensembles of points} of a Riemannian manifold $M$. Parameterized ensemble of points of $M$ is the image of a continuous map $\gamma:\Theta \to M$, where $\Theta$ is a compact set of parameters.…

Optimization and Control · Mathematics 2019-07-08 Andrei Agrachev , Andrey Sarychev

We show that every Banach space $X$ containing an isomorphic copy of $c_0$ has an infinite equilateral set and also that if $X$ has a bounded biorthogonal system of size $\alpha$ then it can be renormed so as to admit an equilateral set of…

Functional Analysis · Mathematics 2013-04-25 S. K. Mercourakis , G. Vassiliadis

We prove that a WLD subspace of the space $\ell_\infty^c(\Gamma)$ consisting of all bounded, countably supported functions on a set $\Gamma$ embeds isomorphically into $\ell_\infty$ if and only if it does not contain isometric copies of…

Functional Analysis · Mathematics 2018-07-17 William B. Johnson , Tomasz Kania

We prove that, for every cardinal number $\alpha\geq {\mathfrak c}$, there exists a metrizable space $X$ with $|X|=\alpha$ such that for every pair of quasiorders $\leq_1$, $\leq_2$ on a set $Q$ with $|Q| \leq \alpha$ satisfying the…

General Topology · Mathematics 2007-05-23 Vera Trnkova

We show that if the Szlenk index of a Banach space $X$ is larger than the first infinite ordinal $\omega$ or if the Szlenk index of its dual is larger than $\omega$, then the tree of all finite sequences of integers equipped with the…

Functional Analysis · Mathematics 2017-09-27 F. Baudier , N. J. Kalton , G. Lancien

Given a space $X$, a $\sigma$-algebra $\mathfrak{B}$ on $X$ and a measurable map $T:X \to X$, we say that a measure $\mu$ is half-invariant if, for any $B \in \mathfrak{B}$, we have $\mu(T^{-1}(B)\leq \mu (B)$. In this note we present a…

Dynamical Systems · Mathematics 2012-03-28 Maria Carvalho , Fernando Moreira

A strong submeasure on a compact metric space X is a sub-linear and bounded operator on the space of continuous functions on X. A strong submeasure is positive if it is non-decreasing. By Hahn-Banach theorem, a positive strong submeasure is…

Dynamical Systems · Mathematics 2019-01-11 Tuyen Trung Truong

A recent result of T.~Abrahamsen, P.~H\'ajek and S.~Troyanski states that a separable Banach space is almost square if and only if there exists $h\in S_{X^{****}}$ such that $\|x+h\|=\max\{\|x\|,1\}$ for all $x\in X$. The proof passes…

Functional Analysis · Mathematics 2021-10-28 Antonio Avilés , Gonzalo Martínez-Cervantes , Abraham Rueda Zoca