Timeline for Applications of infinite graph theory
Current License: CC BY-SA 3.0
4 events
| when toggle format | what | by | license | comment | |
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| Jun 9, 2017 at 18:35 | comment | added | Peter Heinig | Right, thanks for pointing out, the comment conflated "model of set theory" with "(classifying set of) a class of sets often studied in set-theory". For example, $\Pi_1^1$-sets are often classified by well-founded trees. | |
| Jun 9, 2017 at 18:15 | comment | added | Joel David Hamkins | No, a model of set theory is not a tree, in anyone's sense. (And a model of set theory needn't be well-founded). But $\in$ is a directed binary relation, which makes it a directed graph. | |
| Jun 9, 2017 at 18:11 | comment | added | Peter Heinig | Yes and no: such a model is a well-founded tree in the set-theorists' sense of tree. This sense is different from the graph-theorists' sense of tree. Not that there would be anything wrong with that. | |
| Jun 9, 2017 at 18:03 | history | answered | Joel David Hamkins | CC BY-SA 3.0 |