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Timeline for "Thickening" an arc on a 2-manifold

Current License: CC BY-SA 4.0

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Sep 9, 2022 at 11:29 comment added Tim Campion [Text continued from Palina Severyna's answer which was converted to a comment:] Finally, I've read the thread mathoverflow.net/questions/57766/… (you marked my question as duplicate to it) and couldn't understand in the argument of Bill Thurston, why the original arc can be identified with one of its two pre-images under the branched cover $z \to z^2$ of a sphere. What is a homeomorphism between them? I also would like to remark that I may not assume that the surface permits a triangulation.
Sep 9, 2022 at 9:55 comment added Palina Severyna Unfortunately I don't have enough reputation to write a comment, so I have to use the answer field to ask for the clarification for the first proof idea here. @SamNead, could you please explain how one can apply the Jordan-Schoenflies to a surface? The statement of the theorem holds for now for a plane only. Then, it's also not so clear, why, for exmaple, a spiral arc $[0, 1] \to \mathbb{C}$, $t \mapsto (1 - t)e^{i \frac{1}{1 - t}}$, completed to a Jordan curve, has necesseraly an annulus neighbourhood. How exactly does it follow from the Jordan-Schoenflies? Finally, I've read the thread https
Aug 30, 2022 at 1:25 comment added Sam Nead Yes, very relevant! Also, I notice that I, sometime in the past voted, up that post and some of the answers... We should probably mark this question (and my answer) as a duplicate.
Aug 30, 2022 at 0:35 comment added Jim Conant Belevant: mathoverflow.net/questions/57766/…
Aug 29, 2022 at 23:51 history edited Sam Nead CC BY-SA 4.0
added "two"
Aug 29, 2022 at 23:28 history answered Sam Nead CC BY-SA 4.0