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Nov 22, 2021 at 10:33 comment added GH from MO The condition "bounded" can be omitted, since any continuous function on $\widehat{\mathbb{C}}$ is bounded. For the same reason, the case of $w=\infty$ does not occur, hence it can be disregarded in the proof. Finally, one also needs to assume that $f(\infty)\neq 0$, along with $\infty\not\in E$, in order for the $z_j$'s to lie in $\mathbb{C}$.
Feb 21, 2019 at 20:10 comment added Malik Younsi @FedorPetrov Thanks!
Feb 21, 2019 at 20:09 comment added Malik Younsi @OlegEroshkin I was not aware of Shabat's book, thanks for the reference!
Feb 20, 2019 at 21:06 history edited Fedor Petrov CC BY-SA 4.0
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Feb 20, 2019 at 20:19 comment added Oleg Eroshkin Shabat's book (Introduction to complex analysis vol.1) has this theorem as a problem. The shortest proof that I know is based on a notion of degree of the map. A map $f\colon S^2\to\mathbb{C}$ is of degree 0. Let $w\in f(S^2)$. If $f$ is holomorphic at $z\in f^{-1}(w)$, then $z$ makes a positive contribution to $\mathrm{deg} f$ since $f$ preserve the orientation. So it must be compensated by contribution of points in $E$.
Feb 20, 2019 at 19:19 comment added Fedor Petrov @Kalim I modified the proof a bit, hopefully it became better
Feb 20, 2019 at 19:16 history edited Fedor Petrov CC BY-SA 4.0
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Apr 5, 2018 at 3:01 comment added Piotr Hajlasz Let us continue this discussion in chat.
Apr 5, 2018 at 2:41 comment added Piotr Hajlasz I have to think about the example carefully since I want to understand all details. I like your post a lot. There is a result of Salem-Zygmund about holomorphic functions on the unit disc whose boundary values form a Peano type curve. Your example fits into this well. If the example is your original contribution you could expand it and publish in Amer. Math. Monthly.
Apr 5, 2018 at 2:18 history edited Malik Younsi CC BY-SA 3.0
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Apr 5, 2018 at 0:23 history edited Malik Younsi CC BY-SA 3.0
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Apr 4, 2018 at 22:43 history edited Piotr Hajlasz CC BY-SA 3.0
Added link to MathSciNet and separated example from the theorem.
S Apr 4, 2018 at 21:17 history answered Malik Younsi CC BY-SA 3.0
S Apr 4, 2018 at 21:17 history made wiki Post Made Community Wiki by Malik Younsi