Abstract
Some classes of metric spaces satisfying properties stronger than completeness but weaker than compactness have been studied by many authors over the years. One such significant family consists of those metric spaces on which every real-valued continuous function is uniformly continuous, which are widely known as Atsuji spaces or UC spaces. Recently in 2014, two new kinds of complete metric spaces are introduced, namely Bourbaki-complete and cofinally Bourbaki-complete metric spaces, whose idea has come from some new classes of sequences acting as generalizations of Cauchy sequences. Our major goal is to give several new equivalent conditions for metric spaces whose completions are one of the aforesaid spaces, especially in terms of some functions, sequences and geometric functionals.
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Dedicated to Professor Robert A. McCoy
The first author is supported by the National Board for Higher Mathematics (NBHM), India.
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Aggarwal, M., Kundu, S. More on variants of complete metric spaces. Acta Math. Hungar. 151, 391–408 (2017). https://doi.org/10.1007/s10474-016-0682-2
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DOI: https://doi.org/10.1007/s10474-016-0682-2
Key words and phrases
- complete metric space
- Bourbaki-complete metric space
- continuous function
- Cauchy-continuous function
- Atsuji space