Archive for Mathematical Logic

, Volume 58, Issue 3–4, pp 353–358 | Cite as

On uniformly continuous functions between pseudometric spaces and the Axiom of Countable Choice

  • Samuel G. da SilvaEmail author


In this note we show that the Axiom of Countable Choice is equivalent to two statements from the theory of pseudometric spaces: the first of them is a well-known characterization of uniform continuity for functions between (pseudo)metric spaces, and the second declares that sequentially compact pseudometric spaces are \(\mathbf {UC}\)—meaning that all real valued, continuous functions defined on these spaces are necessarily uniformly continuous.


Axiom of Countable Choice Pseudometric spaces Uniform continuity 

Mathematics Subject Classification

Primary 03E25 Secondary 54E35 


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The author is grateful to his colleague Marcelo D. Passos for calling his attention to characterizations of uniform continuity of real valued functions which do not rely on the Lebesgue covering number. The author also acknowledges the anonymous referee for his/her careful reading of the manuscript and for a number of helping comments and corrections which improved the presentation of the paper.


Funding was provided by FAPESB (Grant No. APP0072/2016).


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Instituto de MatemáticaUniversidade Federal da Bahia Campus OndinaSalvadorBrazil

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