Timeline for Planarity of a subgraph
Current License: CC BY-SA 4.0
4 events
| when toggle format | what | by | license | comment | |
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| Apr 17, 2020 at 14:53 | comment | added | Gerhard Paseman | I'm suggesting an idea for how to construct a variety of examples. Let some sufficiently complicated graph class be called C. Make your post as above, but replace planar by C. I'm suggesting a counterexample by picking a graph outside of C, putting small weights on the edges, and large weights on the complementary edges. Gerhard "Trying To Throw Off Balance" Paseman, 2020.04.17. | |
| Apr 17, 2020 at 14:39 | comment | added | Manfred Weis | @GerhardPaseman are you trying to enforce a violation of one of Kuratowski's criteria for the planarity of graphs? $K_{3,3}$ is a Moebius ladder graph and thus locally planar, but not globally by virtue of the twist. At least a clever idea for a possible counter example. | |
| Apr 17, 2020 at 14:19 | comment | added | Gerhard Paseman | Probably not. Let V have six vertices, and put small weights on a K3,3 subgraph and large weights on the rest of the edges. I suspect there is a weighting that will leave the nonplanar digraph after removing the heavy edges. Gerhard "Weighted Graphs Can Be Tricky" Paseman, 2020.04.17. | |
| Apr 17, 2020 at 14:02 | history | asked | Manfred Weis | CC BY-SA 4.0 |