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Nov 17, 2023 at 11:53 comment added Roman @MarkGrant, Yes, the evaluation map ${\rm Homeo_0}(S)/{\rm Homeo_0}(S, V) \rightarrow C(S, n)$ is a homeomorphism. The subtlest part is the openness of this map. The standard proof of the openness seems also to extend to the openness of the map in my question. I think, I can then to do an inductive argument to show that my map is a bijection, but it is a bit annoying. I wonder if nobody came to this before, or if there is a simpler proof.
Nov 17, 2023 at 11:49 comment added Roman @alesia, I'd love to see such an argument, but unfortunately, I couldn't so far produce it myself. Please note that all the homeomorphisms in question are supposed to be isotopic to identity on $S$.
Nov 17, 2023 at 7:06 comment added Mark Grant There is an "evaluation at $V$" map from $\mathrm{Homeo}_0(S)$ to $C(S,n)$, which I believe is a fibration with fibre $\mathrm{Homeo}_0(S,V)$. Does this imply that the quotient is in fact $C(S,n)$?
Nov 16, 2023 at 22:27 comment added alesia doesn't this follow shortly enough from the isomorphism between braid groups and mapping class groups?
Nov 16, 2023 at 22:11 history edited Roman CC BY-SA 4.0
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Nov 16, 2023 at 20:57 history asked Roman CC BY-SA 4.0