English

The comb-like representations of cellular ordinal balleans

General Topology 2016-03-30 v1

Abstract

Given two ordinal λ\lambda and γ\gamma, let f:[0,λ)[0,γ)f:[0,\lambda) \rightarrow [0,\gamma) be a function such that, for each α<γ\alpha<\gamma, sup{f(t):t[0,α]}<γ.\sup\{f(t): t\in[0, \alpha]\}<\gamma. We define a mapping df:[0,λ)×[0,λ)[0,γ)d_{f}: [0,\lambda)\times [0,\lambda) \longrightarrow [0,\gamma) by the rule: if x<yx<y then df(x,y)=df(y,x)=sup{f(t):t(x,y]}d_{f}(x,y)= d_{f}(y,x)= \sup\{f(t): t\in(x,y]\}, d(x,x)=0d(x,x)=0. The pair ([0,λ),df)([0,\lambda), d_{f}) is called a γ\gamma-comb defined by ff. We show that each cellular ordinal ballean can be represented as a γ\gamma-comb. In {\it General Asymptology}, cellular ordinal balleans play a part of ultrametric spaces.

Keywords

Cite

@article{arxiv.1603.08713,
  title  = {The comb-like representations of cellular ordinal balleans},
  author = {I. V. Protasov and K. D. Protasova},
  journal= {arXiv preprint arXiv:1603.08713},
  year   = {2016}
}

Comments

5 pages, preprint