A difference between continuous and absolutely continuous norms in Banach function spaces

On examples we show a difference between a continuous and absolutely continuous norm in Banach function spaces.     

BV Solutions to Evolution Problems with Time-Dependent Domains

In a Hilbert space H we consider evolution problems -du(t) A(t)u(t) on some interval [0, T], where every A(t): D(A(t)) 2 H is a maximal monotone operator, and the correspondence t A(t) is – in a suitable sense – of bounded variation or absolutely continuous.     

Onp-adic functions preserving Haar measure

Let {a _n } _n ^=0/ be a uniformly distributed sequence ofp-adic integers. In the present paper we study continuous functions close to differentiable ones (with respect to thep-adic metric); for these functions, either the sequence {f(a _n )} _n ^=0/ is uniformly distributed over the ring ofp-adic integers or, for all sufficiently largek, the sequences {f _k (_k(a_n))} _n ^=0/ are uniformly distributed over the residue class ring modp ^k , where _k is the canonical epimorphism of the ring ofp-adic integers to the residue class ring modp ^k andf _k is the function induced byf on the residue class ring modp ^k (i.e.,f k _(x) =f( _k (x)) (modp ^k )). For instance, these functions can be used to construct generators of pseudorandom numbers.Translated fromMatematicheskie Zametki, Vol. 63, No. 6, pp. 935–950, June, 1998.In conclusion, the author wishes to express his deep gratitude to V. S. Anashin for permanent attention to this research and for support.     

Rkk (X)-nucléarité (d‘après; G. Skandalis)

We define a notion of nuclearity for C(X)-C^*-algebras yielding the same results of semi-exactness, for Kasparovs bifunctor RKK(X), as those obtained by Skandalis in the case X=. We connect explicitly this new notion of nuclearity with those already known.     

Van Douwen's problem on 0-dimensional images of ordered compacta

A compact 0-dimensional space has a -separating rank 1 family of clopen sets iff it is the continuous image of a compact 0-dimensional linearly ordered space.

     

Projection Method for Moment Bounds on Order Statistics from Restricted Families: II. Independent Case

The method of projection, proposed in Part I, is applied to derive sharp moment bounds for the expectations of order statistics based onindependentsamples from restricted families of distributions. Three families are considered: life distributions with decreasing failure density, decreasing failure rate, and symmetric unimodal ones. The respective bounds are also numerically compared with those for general populations in both the dependent and independent cases.     

Continuous Selections for Continuous Set-Valued Mappings and Finite-Dimensional Sets

The paper is devoted to selection theorems for continuous set-valued mappings which are not necessarily convex-valued on finite-dimensional subsets of the domain. As a result, we get natural generalizations of the famous Kuratowski–Dugundji extension theorem. The technique, developed in the paper, applies to l.s.c. mappings with paracompact, or similar, domain as well. Also, it leads us to a new construction of set-valued continuous selections that involves dimension-type arguments.     

On the Spectrum of the Surface Maryland Model

We study spectral properties of the discrete Laplacian H on the half space Z₊ ^d+1 = Z^d× Z₊ with a boundary condition (n,-1) = tan( ... n + )(n,0), where [0,1]^d. We denote by H₀ the Dirichlet Laplacian on Z₊ ^d+1. Whenever is independent over rationals (H) = R. Khoruzenko and Pastur have shown for a set of 's of Lebesgue measure 1, the spectrum of H on R\ (H₀) is pure point and that corresponding eigenfunctions decay exponentially. In this Letter we show that if is independent over rationals, then the spectrum of H on the set (H₀) is purely absolutely continuous.     

A characterization of strongly measurable Kurzweil–Henstock integrable functions and weakly continuous operators

We give necessary and sufficient conditions for the Kurzweil–Henstock integrability of functions given by , where x_n belong to a Banach space and the sets (E_n)_n are measurable and pairwise disjoint. Also weakly completely continuous operators between Banach spaces are characterized by means of scalarly Kurzweil–Henstock integrable functions.     

Weak laws of large numbers for cooperative gamblers

Based on a stochastic extension of Karamata’s theory of slowly varying functions, necessary and sufficient conditions are established for weak laws of large numbers for arbitrary linear combinations of independent and identically distributed nonnegative random variables. The class of applicable distributions, herein described, extends beyond that for sample means, but even for sample means our theory offers new results concerning the characterization of explicit norming sequences. The general form of the latter characterization for linear combinations also yields a surprising new result in the theory of slow variation. Work was supported in part by the Hungarian Scientific Research Fund, Grant T048360, and carried out within the Analysis and Stochastics Research Group of the Hungarian Academy of Sciences.