English

Decompositions of set-valued mappings

General Topology 2019-10-31 v2

Abstract

Let XX be a set, BXB_{X} denotes the family of all subsets of XX and F:XBXF: X \longrightarrow B_{X} be a set-valued mapping such that xF(x)x \in F(x), supxXF(x)<κsup_{x\in X} | F(x)|< \kappa, supxXF1(x)<κsup_{x\in X} | F^{-1}(x)|< \kappa for all xXx\in X and some infinite cardinal κ\kappa. Then there exists a family F\mathcal{F} of bijective selectors of FF such that F<κ|\mathcal{F}|<\kappa and F(x)={f(x):fF}F(x) = \{ f(x): f\in\mathcal{F}\} for each xXx\in X. We apply this result to GG-space representations of balleans.

Keywords

Cite

@article{arxiv.1908.03911,
  title  = {Decompositions of set-valued mappings},
  author = {Igor Protasov},
  journal= {arXiv preprint arXiv:1908.03911},
  year   = {2019}
}

Comments

set-valued mapping, selector, ballean

R2 v1 2026-06-23T10:44:40.600Z