Timeline for Directed subposet of a poset containing the minimal elements
Current License: CC BY-SA 3.0
7 events
| when toggle format | what | by | license | comment | |
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| Aug 20, 2014 at 11:37 | comment | added | Werner Thumann | Thanks Paul for the keywords, I will have to look them up. I used the definition of E in the context of arxiv.org/abs/1407.5171 Definition 6.3. But I have the feeling that there is more behind that definition and that's why I'm asking. | |
| Aug 17, 2014 at 17:37 | history | edited | Paul Taylor | CC BY-SA 3.0 |
added 255 characters in body
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| Aug 17, 2014 at 16:36 | comment | added | Paul Taylor | I had in mind that $E$ would get closed under directed joins too. But Werner gave us no idea of where his construction came from and his presentation suggested that is was not definitive but open to experimentation. I tried to make what sense of it I could. | |
| Aug 17, 2014 at 16:12 | comment | added | Joel David Hamkins | It seems to me more generally that in any separative partial order, the only co-closure is the identity map, but such orders can have nontrivial $E$. | |
| Aug 17, 2014 at 16:03 | comment | added | Joel David Hamkins | Paul, suppose that $P$ consists of the nonempty subsets of a fixed infinite set, ordered by $\subseteq$. In this case, the only co-closure $f$ seems to be the identity map, whose image would be the whole of $P$, but $E$ would consist precisely of the finite subsets. | |
| Aug 17, 2014 at 14:46 | comment | added | Paul Taylor | Whoever you are, why have you down-voted me? | |
| Aug 17, 2014 at 14:03 | history | answered | Paul Taylor | CC BY-SA 3.0 |