Abstract
Two classical results characterizing regularity of a convergence space in terms of continuous extensions of maps on one hand, and in terms of continuity of limits for the continuous convergence on the other, are extended to convergence-approach spaces. Characterizations are obtained for two alternative extensions of regularity to convergence-approach spaces: regularity and strong regularity. The results improve upon what is known even in the convergence case. On the way, a new notion of strictness for convergence-approach spaces is introduced.
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Colebunders, E., Mynard, F. & Trott, W. Function Spaces and Contractive Extensions in Approach Theory: The Role of Regularity. Appl Categor Struct 22, 551–563 (2014). https://doi.org/10.1007/s10485-013-9321-z
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DOI: https://doi.org/10.1007/s10485-013-9321-z
Keywords
- Regularity
- Strong regularity
- Convergence space
- Convergence-approach space
- Approach space
- Strict subspace
- Continuous extension
- Contractive extension
- Default of contraction
- Continuous convergence
- Diagonal axioms