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Related papers: A new characterization of Baire class 1 functions

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We define a family of three related reducibilities, $\leq_T$, $\leq_{tt}$ and $\leq_m$, for arbitrary functions $f,g:X\rightarrow\mathbb R$, where $X$ is a compact separable metric space. The $\equiv_T$-equivalence classes mostly coincide…

Logic · Mathematics 2019-06-19 Adam R. Day , Rod Downey , Linda Brown Westrick

During the last few decades E. S. Thomas, S. J. Agronsky, J. G. Ceder, and T. L. Pearson gave an equivalent definition of the real Baire class 1 functions by characterizing their graph. In this paper, using their results, we consider the…

Classical Analysis and ODEs · Mathematics 2017-06-13 Balázs Maga

In 1990 Kechris and Louveau developed the theory of three very natural ranks on the Baire class $1$ functions. A rank is a function assigning countable ordinals to certain objects, typically measuring their complexity. We extend this theory…

Logic · Mathematics 2016-10-25 Márton Elekes , Viktor Kiss , Zoltán Vidnyánszky

We present a new definition of Euler Gamma function. From the complex analysis and transalgebraic viewpoint, it is a natural characterization in the space of finite order meromorphic functions. We show how the classical theory and formulas…

Complex Variables · Mathematics 2023-12-08 Ricardo Pérez-Marco

Let $X$ be a paracompact topological space and $Y$ be a Banach space. In this paper, we will characterize the Baire-1 functions $f:X\rightarrow{Y}$ by their graph: namely, we will show that $f$ is a Baire-1 function if and only if its graph…

Classical Analysis and ODEs · Mathematics 2026-05-20 Balázs Maga

On any metric space, I provide an intrinsic characterization of those complex-valued functions which are uniform limits of Lipschitz functions. There are applications to function theory on complete Riemannian manifolds and, in particular,…

Functional Analysis · Mathematics 2021-05-18 L. A. Coburn

Recently some Mathematician extend the notion of Baire one functions. We give some nice relations between this subring and some nice functions rings on a topological spaces.

General Topology · Mathematics 2021-06-08 Mohammad Reza Ahmadi Zand , Zahra Khosravi

We generalize the classical Bernstein theorem concerning the constructive description of classes of functions uniformly continuous on the real line. The approximation of continuous bounded functions by entire functions of exponential type…

Complex Variables · Mathematics 2008-03-11 Vladimir Andrievskii

We compare possibilities of extension of bounded and unbounded Baire-one functions from subspaces of topological spaces.

General Topology · Mathematics 2018-10-30 Olena Karlova , Volodymyr Mykhaylyuk

We prove the following two results. 1. If $X$ is a completely regular space such that for every topological space $Y$ each separately continuous function $f:X\times Y\to\mathbb R$ is of the first Baire class, then every Lindel\"of subspace…

General Topology · Mathematics 2016-01-21 V. V. Mykhaylyuk

We generalize the Lebesgue-Hausdorff Theorem on the characterization of Baire-one functions for $\sigma$-strongly functionally discrete mappings defined on arbitrary topological spaces

General Topology · Mathematics 2015-12-01 Olena Karlova

Recently, there emerges different versions of beta function and hypergeometric functions containing extra parameters. Gaining enlightenment from these ideas, we will first introduce a new extension of generalized hypergeometric function and…

Classical Analysis and ODEs · Mathematics 2013-02-12 Luo Minjie

Inspired by a recent work of Mesnager, we present several new infinite families of quadratic ternary bent, near-bent and 2-plateaued functions from some known quadratic ternary bent functions. Meanwhile, the distribution of the Walsh…

Information Theory · Computer Science 2015-08-17 Guangkui Xu , Xiwang Cao

We investigate the Baire classification of mappings $f:X\times Y\to Z$, where $X$ belongs to a wide class of spaces, which includes all metrizable spaces, $Y$ is a topological space, $Z$ is an equiconnected space, which are continuous in…

General Topology · Mathematics 2014-07-23 Olena Karlova , Volodymyr Maslyuchenko , Volodymyr Mykhaylyuk

We study the maps between topological spaces whose composition with Baire class $\alpha$ maps also belongs to the $\alpha$'th Baire class and give characterizations of such maps

General Topology · Mathematics 2015-12-01 Olena Karlova , Volodymyr Mykhaylyuk

We study several properties of equi-Baire 1 families of functions between metric spaces. We consider the related equi-Lebesgue property for such families. We examine the behaviour of equi-Baire 1 and equi-Lebesgue families with respect to…

General Topology · Mathematics 2023-04-18 Marek Balcerzak , Lubica Hola , Dusan Holy

We prove an extension theorem (with non-tangential limits) for vector-valued Baire one functions. Moreover, at every point where the function is continuous (or bounded), the continuity (or boundedness) is preserved. More precisely: Let $H$…

Functional Analysis · Mathematics 2016-05-25 Jan Kolář , Martin Koc

The theory of ordinal ranks on Baire class 1 functions developed by Kechris and Loveau was recently extended by Elekes, Kiss and Vidny\'{a}nszky to Baire class $\xi$ functions for any countable ordinal $\xi\geq1$. In this paper, we answer…

Functional Analysis · Mathematics 2017-01-23 Denny H. Leung , Hong-Wai Ng , Wee-Kee Tang

It is proved that every function of finite Baire index on a separable metric space $K$ is a $D$-function, i.e., a difference of bounded semi-continuous functions on $K$. In fact it is a strong $D$-function, meaning it can be approximated…

Functional Analysis · Mathematics 2009-09-25 Fouad Chaatit , Vania Mascioni , Haskell P. Rosenthal

Beurling slow variation is generalized to Beurling regular variation. A Uniform Convergence Theorem, not previously known, is proved for those functions of this class that are measurable or have the Baire property. This permits their…

Classical Analysis and ODEs · Mathematics 2013-07-22 N. H. Bingham , A. J. Ostaszewski