Talk:Lower Set with no Greatest Element is Open in GO-Space

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Open sets

There are many ways to talk about open sets. A very common way is to identify the space with its underlying set, and just say "$x \in X$" or "$U$ is open in $X$". To be super-formal about it, you can either say "$U$ is open in $(X,\tau)$" or "$U \in \tau$". The former is clunky while the latter takes an extra translation step to read. If you have defined $T = (X, \tau)$ then you can say "open in $T$", but that's probably the worst of all, because it requires you to break out of your reading to go look up what the heck $T$ was. --Dfeuer (talk) 15:26, 23 February 2013 (UTC)

All I'm saying is that there should be links to the definition. — Lord_Farin (talk) 15:28, 23 February 2013 (UTC)
Understood. All I'm saying is that as I've been working on these topological matters I've been finding it very hard to describe things in a way that's easy to read, and this is one of the barriers to that. --Dfeuer (talk) 15:32, 23 February 2013 (UTC)
In which case, FFR please raise issues on directly relevant pages (in this case Definition:Open Set (Topology)). There may be people watching those but not some relatively new and quite unrelated page. I perceive it as admissible to introduce some common shorthands if there is no risk of ambiguity (e.g. when only one top.sp is under consideration) but we would have to document such conventions properly on the relevant defining pages. — Lord_Farin (talk) 15:38, 23 February 2013 (UTC)