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Timeline for Heat kernel for non bounded domains

Current License: CC BY-SA 3.0

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Feb 21, 2015 at 8:49 vote accept Jop Kop
Feb 21, 2015 at 6:57 comment added Andrew In this question math.stackexchange.com/questions/266785/… it is proved for harmonic functions. The same argument holds for solutions of the heat equation.
Feb 21, 2015 at 6:28 comment added Jop Kop Thank you for this wonderful argument! I suppose the pointwise limit still satisfies the heat equation, but I'm not sure why this is the case. Is this easy to see?
Feb 20, 2015 at 15:15 comment added Andrew Yes, it doesn't directly work. One has to assume some conditions at infinity. Here is another argument. Denote $B_R=\{|x|<R\}$ a ball in $\mathbb R^n$. Suppose that there exists a monotone sequence $R_n\to\infty$ s.t. $U\cap B_{R_{n}}$ is regular enough and let $H_n$ be the corresponding solutions. Then $H_n\le K$ and for fixed values of parameters $(x,y,t)$ sequence $H_n$ is increasing. In such case there exists a pointwise limit of $H_n$, which will have all the required properties.
Feb 19, 2015 at 18:15 review Low quality posts
Feb 19, 2015 at 18:28
Feb 19, 2015 at 18:08 comment added Jop Kop Hello Andrew. Which maximum principle do you refer to? Usually the maximum principle is proven only for bounded domains. In my case the domain is unfortunately unbounded.
Feb 19, 2015 at 18:04 history edited Andrew CC BY-SA 3.0
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Feb 19, 2015 at 17:58 history answered Andrew CC BY-SA 3.0