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Timeline for A question of uniqueness

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Aug 4, 2020 at 14:20 vote accept Paul
Aug 4, 2020 at 13:56 comment added Willie Wong @cerise: I had taken your convergence $\lim_{y\to\infty} u(x,y) = 0$ to mean convergence with respect to some reasonable function norm (say $L^\infty$). If you only wished to have pointwise convergence and no more, then as Eremenko said there are counterexamples.
Aug 4, 2020 at 6:09 history edited Paul CC BY-SA 4.0
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Aug 4, 2020 at 4:57 history edited Paul CC BY-SA 4.0
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Aug 4, 2020 at 4:51 history edited Paul CC BY-SA 4.0
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Aug 4, 2020 at 4:19 comment added Paul @Willie Wong I tried to apply the maximum principle with your indication with $ \Omega_t $ but without success. Can you give your answer because I do not see why it is easy and especially that A.Ermenko says that there is a counter example.
Aug 4, 2020 at 3:13 answer added Alexandre Eremenko timeline score: 3
Aug 3, 2020 at 18:02 comment added Willie Wong Let $\Omega_t = \Omega \cap \{ y < t\}$. Apply the maximum principle for $u$ on $\Omega_t$. Take $t\to \infty$.
Aug 3, 2020 at 17:25 comment added Paul @Willie Wong the maximum principale is available if $\Omega$ a bounded domain theoreme 2.17 math.ucdavis.edu/~hunter/pdes/ch2.pdf
Aug 3, 2020 at 15:25 review Close votes
Aug 10, 2020 at 3:03
Aug 3, 2020 at 15:10 comment added Willie Wong Anyway, for the method you choose: $u(x,R) \frac{du}{dy}(x,R) = \frac12 \frac{d}{dy} |u(x,y)|^2 \Big]_{y = R}$. If the lim of $u(x,y)$ tends to zero, there exists some $R$ for which the integral of this derivative is negative.
Aug 3, 2020 at 15:07 comment added Willie Wong Isn't it easier to just use maximum principle?
Aug 3, 2020 at 14:42 history asked Paul CC BY-SA 4.0