Abstract
We prove that \(C_p(X)\) is pseudocomplete if and only if it has a dense cofinally Polish subspace. This result provides positive answers to two open questions from (Niknejad in Bull Belg Math Soc 25(3):439–452, 2018). We also establish that a space X is cofinally Polish if and only if its Hewitt extension \(\upsilon X\) is cofinally Polish and show that a subspace X of an ordinal is cofinally Polish if and only if X has countable extent.
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Tkachuk, V.V. The space \(C_p(X)\) is cofinally Polish if and only if it is pseudocomplete. RACSAM 115, 68 (2021). https://doi.org/10.1007/s13398-021-01005-7
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DOI: https://doi.org/10.1007/s13398-021-01005-7
Keywords
- Cofinally Polish space
- Pseudocomplete space
- Pseudocompact space
- Function space
- Hewitt extension
- Subspace of an ordinal
- extent