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Malik Younsi

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Name Malik Younsi
Member for 3 years
Seen 4 hours ago
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Location Québec
Age
Jun
6
comment On the existence of a holomorphic logarithm
@Margaret Friedland : Thank you for the reference. It seems like a good book, but I didn't find what I'm looking for.
Jun
5
comment On the existence of a holomorphic logarithm
Yes, this is the proof I had in mind, thank you. However, I was wondering : do you have any idea where I could look to find a reference for this result? It is quite natural, so I am pretty sure it appears somewhere in the literature, but I couldn't find anything.
May
31
comment On the existence of a holomorphic logarithm
@Andreas Blass : Yes indeed, but I meant under which conditions on $\Omega$ and $f$ does the above holds. In particular, I think it is true if $f$ does not reverse orientation of curves inside $\Omega$.
May
31
comment On the existence of a holomorphic logarithm
@Etienne Matheron : In general, $f(z)=(z-a)^2$ is not necessarily one-to-one on $\Omega$. You probably mean that $f(z)=1/(z-a)$ is a counterexample.
May
31
comment Is the homeomorphism class of a connected open set of C determined by its fundamental group?
@EtienneMatheron : The unit disk is homeomorphic to $\mathbb{C}$, for example via $f(z)=z/(1-|z|^2)$. These sets are not conformally equivalent, though.
May
31
revised On the existence of a holomorphic logarithm
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May
31
revised On the existence of a holomorphic logarithm
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May
31
revised On the existence of a holomorphic logarithm
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May
31
comment On the existence of a holomorphic logarithm
We have $e^g=-1/z^2$, and thus $e^{-g}=-z^2$. How do you obtain $e^{-2g}=z$? But I believe this gives a counter-example because -z^2 does not have a holomorphic logarithm on $\mathbb{C} \setminus \{0\}$. Clearly I overlooked something this morning... Thank you
May
31
revised On the existence of a holomorphic logarithm
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May
31
asked On the existence of a holomorphic logarithm
May
27
comment Riemann mapping
Welcome to MO, Maxime Fortier Bourque!
Apr
3
answered functions of one complex variable: geometric theory
Mar
30
awarded  Popular Question
Mar
12
comment On the set of zero radial limits of bounded analytic functions
@Giuseppe : Thank you!
Mar
12
comment On the set of zero radial limits of bounded analytic functions
Thank you very much for the interesting references, I will take a look at them.
Mar
10
comment On the set of zero radial limits of bounded analytic functions
I'm having some problem with LaTex in the definition of $Z_f$... Does someone know how to fix that?
Mar
10
asked On the set of zero radial limits of bounded analytic functions
Feb
20
comment Undecidability and holomorphic functions (Reference request)
The proof is very elegant, and it appears in "Proof from the Book" by Aigner and Ziegler.
Feb
8
awarded  Fanatic
Jan
29
awarded  Enlightened
Jan
29
awarded  Nice Answer
Jan
28
comment When does continuity imply holomorphy?
@EmilJeÅ™ábek : I didn't know about the removability criterion for the Hölder functions. This is very interesting.
Jan
28
accepted When does continuity imply holomorphy?
Jan
28
revised When does continuity imply holomorphy?
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Jan
28
answered When does continuity imply holomorphy?
Jan
28
awarded  Popular Question
Jan
26
comment On the Universality of the Riemann zeta-function
@MarcPalm : Yes, indeed, I see now why we need $\log$. But still, it is a good idea to work with joint universality. Thanks, +1 !
Jan
25
comment On the Universality of the Riemann zeta-function
I mean, the result I'm looking for should contain Voronin's Universality Theorem as a particular case (the case when the complement of $K$ is connected).
Jan
25
comment On the Universality of the Riemann zeta-function
Oh I see, indeed I misread $K_0$ for $K$, sorry about that! But I don't understand why you work with $\log$..?
Jan
24
comment On the Universality of the Riemann zeta-function
See my new edit. I hope it clarifies what I'm looking for here.
Jan
24
revised On the Universality of the Riemann zeta-function
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Jan
24
comment On the Universality of the Riemann zeta-function
This joint universality result is interesting, but what I'm looking for is really a result for compact sets with disconnected complements. Also, just to clarify : I don't want to remove the non-vanishing assumption. I'm fine with it!
Jan
22
awarded  Nice Question
Jan
22
revised On the Universality of the Riemann zeta-function
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Jan
21
revised On the Universality of the Riemann zeta-function
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Jan
21
comment On the Universality of the Riemann zeta-function
@MarcPalm : There is definitely a confusion here. I am talking about Mergelyan's theorem on uniform approximation by rational functions. Of course, uniform approximation by polynomials is only possible in the "connected complement" case! I'll edit the question for more clarity.
Jan
21
comment On the Universality of the Riemann zeta-function
@MarcPalm : See my comment to the question... There is a confusion here.
Jan
21
revised On the Universality of the Riemann zeta-function
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Jan
21
revised On the Universality of the Riemann zeta-function
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Jan
21
revised On the Universality of the Riemann zeta-function
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Jan
21
comment On the Universality of the Riemann zeta-function
@JohannesEbert : Do you think the question is clear now?
Jan
21
revised On the Universality of the Riemann zeta-function
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Jan
21
comment On the Universality of the Riemann zeta-function
Yes, of course, the theorem, as stated, does not hold if you remove the hypothesis that the complement of $K$ is connected. I'm asking if there exists a (different) universality-like result that would work for compact sets with disconnected complements. Sorry if that wasn't clear, I'll edit the question...
Jan
21
revised On the Universality of the Riemann zeta-function
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Jan
21
asked On the Universality of the Riemann zeta-function
Jan
2
awarded  Necromancer
Dec
30
revised A question about the limit of a sequence of pointwise convergent analytic funtions
added 237 characters in body
Dec
30
answered A question about the limit of a sequence of pointwise convergent analytic funtions