ON THE ALMOST PERIODIC AT INFINITY FUNCTIONS FROM HOMOGENEOUS SPACES
Journal Title: Проблемы анализа-Issues of Analysis - Year 2018, Vol 7, Issue 2
Abstract
We consider homogeneous spaces of functions defined on the real axis (or semi-axis) with values in a complex Banach space. We study the new class of almost periodic at infinity functions from homogeneous spaces. The main results of the article are connected to harmonic analysis of those functions. We give four definitions of an almost periodic at infinity function from a homogeneous space and prove them to be equivalent. We also introduce the concept of a Fourier series with slowly varying at infinity coefficients (neither necessarily constant nor necessarily having a limit at infinity). It is proved that the Fourier coefficients of almost periodic at infinity function from a homogeneous space (not necessarily continuous) can be chosen continuous. Moreover, they can be extended on C to bounded entire functions of exponential type. Besides, we prove the summability of Fourier series by the method of Bochner-Fejer. The results were received with essential use of isometric representations and Banach modules theory.
Authors and Affiliations
A. G. Baskakov, I. I. Strukova, V. E. Strukov
ON INEQUALITIES OF HERMITE – HADAMARD TYPE INVOLVING AN s-CONVEX FUNCTION WITH APPLICATIONS
Motivated by a recent paper, the author provides some new integral inequalities of Hermite – Hadamard type involving the product of an s-convex function and a symmetric function and applies these new established inequali...
REDUCED p-MODULUS, p-HARMONIC RADIUS AND p-HARMONIC GREEN’S MAPPINGS
We consider the definitions and properties of the metric characteristics of the spatial domains previously introduced by the author, and their connection with the class of mappings, the particular case of which are the h...
ВЗАИМНЫЕ МУЛЬТИФРАКТАЛЬНЫЕ СПЕКТРЫ I. ТОЧНЫЕ СПЕКТРЫ
It has introduced the fine mutual multifractal spectra for Borel probability measures and received the estimations for these spectra.
STRUCTURE OF KELLER MAPPINGS, TWO-DIMENSIONAL CASE
A Keller map is a polynomial mapping ƒ : Rⁿ → Rⁿ (or Cⁿ → Cⁿ) with the Jacobian Jƒ ≡ const ≠ 0. The Jacobian conjecture was first formulated by O. N. Keller in 1939. In the modern form it supposes injectivity of a Keller...
УСЛОВИЯ ЗВЕЗДООБРАЗНОСТИ ОБЛАСТЕЙ В R^N
Для областей с гладкой границей получен критерий звездообразности области относительно внутренней или граничной точки. В качестве приложения отсюда получаются все известные условия звездообразности биголоморфных отображе...