A. Ostrovsky

collaborators

4 papers

math.GN2026

H-covering Maps in Descriptive Function Theory

Alexey Ostrovsky

We study the preservation of complete metrizability under maps between metric spaces. Two main approaches have been developed in this area: one based on the behavior of maps on cou…

math.GN2026

Finite Decompositions for Initial Baire-1 Subclasses and Their Characterization via Homogeneous Sequences

Alexey Ostrovsky

We announce some results concerning initial subclasses of the Baire-1 functions. First, we obtain a finite decomposition into continuous maps for a basic initial subclass. Second,…

math.GN2011

Preservation of the Borel class under open- $L C$ functions

Alexey Ostrovsky

Let $X$ be a Borel subset of the Cantor set \textbf{C} of additive or multiplicative class $α,$ and $f : X \to Y$ be a continuous function with compact preimages of points onto $Y \…

math.LO2011

$σ$ -homogeneity of Borel sets

Alexey Ostrovsky

We give an affirmative answer to the following question: Is any Borel subset of a Cantor set $C$ a sum of a countable number of pairwise disjoint $h$ -homogeneous subspace…

H-covering Maps in Descriptive Function Theory

Finite Decompositions for Initial Baire-1 Subclasses and Their Characterization via Homogeneous Sequences

Preservation of the Borel class under open-LC functions

σ-homogeneity of Borel sets

Preservation of the Borel class under open- $L C$ functions

$σ$ -homogeneity of Borel sets