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Timeline for Generalizing the $T_0$-axiom

Current License: CC BY-SA 4.0

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Oct 23, 2018 at 21:43 comment added Andrej Bauer I'd just like to point out that the following definition of $T_0$ is more sensible: a space is $T_0$ if any two points that have the same neighborhoods are equal.
Oct 11, 2018 at 18:06 vote accept Dominic van der Zypen
Oct 11, 2018 at 18:04 answer added KP Hart timeline score: 3
Oct 11, 2018 at 17:49 comment added KP Hart I'll save you the trouble.
Oct 11, 2018 at 14:01 comment added KP Hart If $\kappa$ is a limit take a cofinal set, $A$, of cardinals and have $A\cup\{\{\alpha\}:\kappa\le\alpha<\lambda\}$ as a base?
Oct 11, 2018 at 13:51 comment added Will Brian Right -- thanks @KPHart. The space I defined is minimally $T^{\kappa+}_0$. It's not too hard to modify the example to find something minimally $T^\kappa_0$ as well. (I'll type out the details and post them later this morning.)
Oct 11, 2018 at 13:30 comment added KP Hart @WillBrian In this way it looks like $\kappa$ itself is not split, so this is not $T^\kappa_0$. What am I missing?
Oct 11, 2018 at 12:53 comment added Will Brian Can't you just take the topology on $\lambda$ with basis $\{\kappa\} \cup \{\{\alpha\} : \kappa \leq \alpha < \lambda\}$?
Oct 11, 2018 at 11:54 history asked Dominic van der Zypen CC BY-SA 4.0