Given a Banach space X, for n ∈ N and p ∈ (1,∞) we investigate the smallest constant P ∈ (0,∞) for which every f1, . . . , fn : {−1, 1} → X satisfy ∫ {−1,1}n ∥∥∥∥ n ∑ j=1 ∂jfj(ε) ∥∥∥∥ p dμ(ε) 6 P ∫ {−1,1}n ∫ {−1,1}n ∥∥∥∥ n ∑ j=1 δj∆fj(ε) ∥∥∥∥ p dμ(ε)dμ(δ), where μ is the uniform probability measure on the discrete hypercube {−1, 1} and {∂j}j=1 and ∆ = ∑n j=1 ∂j are the hypercube partial derivat...

Let C(X) denote the set of all non-empty closed bounded convex subsets of a normed linear space X. In 1952 Hans R̊adström described how C(X) equipped with the Hausdorff metric could be isometrically embedded in a normed lattice with the order an extension of set inclusion. We call this lattice the R̊adström of X and denote it by R(X). We: (1) outline R̊adström’s construction, (2) examine the struc...

Abstract We introduce and study some operational quantities which characterize the disjointly non-singular operators from a Banach lattice E to space Y when is order continuous, other strictly singular for arbitrary .

For a Banach space X, let B(X) denote the Banach algebra of all continuous linear operators on X. First, we study the lattice of closed ideals in B(Jp), where 1 < p < ∞ and Jp is the pth James space. Our main result is that the ideal of weakly compact operators is the unique maximal ideal in B(Jp). Applications of this result include the following. (i) The Brown–McCoy radical of B(X), which by ...

A Banach space E is c0-saturated if every closed infinite dimensional subspace of E contains an isomorph of c0. A c0-saturated Banach space with an unconditional basis which has a quotient space isomorphic to l2 is constructed. A Banach space E is c0-saturated if every closed infinite dimensional subspace of E contains an isomorph of c0. In [2] and [3], it was asked whether all quotient spaces ...

in this paper, using the fixed point theory in cone metric spaces, we prove the existence of a unique solution to a first-order ordinary differential equation with periodic boundary conditions in banach spaces admitting the existence of a lower solution.

in this paper we introduce new modified implicit and explicit algorithms and prove strong convergence of the two algorithms to a common fixed point of a family of uniformly asymptotically regularasymptotically nonexpansive mappings in a real reflexive banach space with a uniformly g$hat{a}$teaux differentiable norm. our result is applicable in $l_{p}(ell_{p})$ spaces,$1 < p

in  this paper, we investigate the generalizedhyers-ulam-rassias stability for the quartic, cubic and additivefunctional equation$$f(x+ky)+f(x-ky)=k^2f(x+y)+k^2f(x-y)+(k^2-1)[k^2f(y)+k^2f(-y)-2f(x)]$$ ($k in mathbb{z}-{0,pm1}$) in $p-$banach spaces.

We first obtain some properties of a fundamentally nonexpansive self-mapping on a nonempty subset of a Banach space and next show that if the Banach space is having the Opial condition, then the fixed points set of such a mapping with the convex range is nonempty. In particular, we establish that if the Banach space is uniformly convex, and the range of such a mapping is bounded, closed and con...

Introduction. We propose to investigate here the consequences of the identity of each pair chosen from three important generalizations of the relation of betweenness on a line, namely, algebraic betweenness [l, p. 27 J, metric betweenness [3, p. 36], and lattice betweenness [7, Part I I ] . We shall also find an interpretation of metric betweenness in the Banach space of all continuous function...