The comb-like representations of cellular ordinal balleans

Igor Protasov, Ksenia Protasova

Abstract


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


Keywords


ultrametric space, cellular ballean, ordinal ballean, \((\lambda,\gamma)-\)comb

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References


I. Protasov, T. Banakh, D. Repovs, S. Slobodianiuk, Classifying homogeneous cellular ordinal balleans up to course equivalence, preprint (arXiv:1409.3910).

T. Banakh, D. Repovs, Classifying homogeneous ultrametric spaces up to coarse equivalence, preprint (arXiv: 1408.4818).

A. Lambert, G. Uribe Bravo, The comb representation of compact ultrametric spaces, preprint (arXiv: 1602.08246).

I. Protasov, O. Petrenko, S. Slobodianiuk, Asymptotic structures of cardinals, Appl. Gen.Topology 15, N2 (2014), pp.137-146.

I. Protasov, T. Banakh, Ball Structures and Colorings of Groups and Graphs, Math. Stud. Monogr. Ser., Vol.11, VNTL, Lviv, 2003.

I.V. Protasov, A. Tsvietkova, Decomposition of cellular balleans, Topology Proc. 36 (2010), pp.77-83.

I. Protasov, M. Zarichnyi, General Asymptology, Math. Stud. Monogr. Ser., Vol. 12, VNTL, Lviv, 2007.

Roe J., Lectures on Coarse Geometry, Univ. Lecture Series, Vol.31, Amer. Math. Soc, Providence, RI, 2003.


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