Timeline for A countable tight topological group where every countable subset is metrizable
Current License: CC BY-SA 3.0
8 events
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| Apr 13, 2017 at 12:58 | history | edited | CommunityBot |
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| Mar 3, 2015 at 9:51 | comment | added | Tom | Mathieu Baillif, Thank you for your answer and Ramiro de la Vega, thank you for the other example! :-) | |
| Mar 3, 2015 at 9:12 | vote | accept | Tom | ||
| Feb 24, 2015 at 14:25 | comment | added | Mathieu Baillif | @Ramiro. I thought that term "Cantor cube" was reserved for $2^\kappa$ for uncountable $\kappa$. And you are right, the direct sum is a simpler example. | |
| Feb 24, 2015 at 14:21 | comment | added | Ramiro de la Vega | You can also let $X$ be the direct sum of $\omega_1$ copies of $2$. That is the set of all elements of $2^{\omega_1}$ with finite support. It is easier to show that this space is Frechet-Urysohn, and it is not first-countable (hence non-metrizable). | |
| Feb 24, 2015 at 14:18 | comment | added | Ramiro de la Vega | The Cantor space $2^\omega$ is a Cantor cube. | |
| Feb 24, 2015 at 9:54 | comment | added | Mathieu Baillif | $2^\omega$ is the Cantor space, of course, not the Cantor cube. | |
| Feb 23, 2015 at 22:00 | history | answered | Mathieu Baillif | CC BY-SA 3.0 |