Timeline for Between Tietze's and Dugundji's extension theorems
Current License: CC BY-SA 4.0
4 events
| when toggle format | what | by | license | comment | |
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| Feb 10 at 20:12 | vote | accept | Pietro Majer | ||
| Oct 4, 2022 at 13:54 | comment | added | Robert Furber | Pełczyński calls a compact Hausdorff space $X$ such that for all closed $Y \subseteq X$ there exists a bounded linear extension map $C(Y) \rightarrow C(X)$ an almost Dugundji space. In Corollary 8.14 on p. 47 he states that a non-metrizable compact Hausdorff space is not almost Dugundji if it is extremally disconnected, scattered, or has uncountable cellularity. So $\beta \mathbb{N}$ is covered by this, but also e.g. the one-point compactification of an uncountable set. | |
| Oct 4, 2022 at 12:48 | history | edited | Jochen Wengenroth | CC BY-SA 4.0 |
Example added.
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| Oct 4, 2022 at 9:23 | history | answered | Jochen Wengenroth | CC BY-SA 4.0 |