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Timeline for Bounds for analytic circles

Current License: CC BY-SA 4.0

17 events
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Mar 18 at 6:17 vote accept Bo Jonsson
Mar 18 at 6:17
Mar 18 at 6:11 vote accept Bo Jonsson
Mar 18 at 6:12
Mar 18 at 6:09 vote accept Bo Jonsson
Mar 18 at 6:09
Mar 17 at 22:32 comment added Felixson Thank you. I will also stop here. Your point is cristal clear, but my impression is that @bojonsson might be assuming $s$ is on the critical line, or strip. I have posted an answer with some basic comments.
Mar 17 at 0:57 comment added GH from MO @Felixson By Stirling's approximation, one can determine the size of $\xi(s)$ and $f(s)$ very precisely on the positive axis (as $s$ tends to infinity). There is no issue here, really. OK, I must stop now (this site is not designed and not meant for chatting).
Mar 17 at 0:48 comment added Felixson Thank you @GHfromMO. Of course the bound is trivial for bounded p. But the differing speeds at which $\xi(s)$ and $f(s)$ grow to infinity faster than exponentially in the positive axis, is far from trivial...
Mar 17 at 0:31 comment added GH from MO @Felixson If $p$ is bounded, then the $O(e^{\epsilon p})$ bound is true for trivial reasons. Indeed, if $|s|<c$, then $\xi(s)/s=O_c(1)$, hence $|\xi(s)|=O_c(|s|)=O_{c,\epsilon}(e^{\epsilon|s|})$. I will finish this topic here.
Mar 17 at 0:19 comment added Felixson But it seems to me that the problem is still open for circles of sufficiently small radius, since the behaviors of $\xi(s)$ in short intervals is still a mystery. The question is trivial for large p, I agree...
Mar 16 at 23:51 comment added GH from MO @Felixson If $s=p$ is a large positive number, then $\xi(p)$ exceeds $e^p$. More precisely, $\log\xi(p)$ is asymptotically $p\log p$.
Mar 16 at 23:40 comment added Felixson @GHfromMO Ok thank you. I see your point then. Still I'm not convinced that the bound is not satisfied, but I must be missing something...
Mar 16 at 23:26 comment added GH from MO @AlekseiKulikov Right. I fixed my post.
Mar 16 at 23:17 history edited GH from MO CC BY-SA 4.0
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Mar 16 at 23:11 comment added GH from MO @Felixson My previous version was partly nonsense, sorry about that. I have updated my post.
Mar 16 at 23:10 history edited GH from MO CC BY-SA 4.0
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Mar 16 at 23:05 comment added Aleksei Kulikov It is not of order $0$, but of order $1$ and minimal type.
Mar 16 at 23:03 comment added Felixson It is well known that there exist certain entire functions of order 1, that satisfy the bound mentioned. That all entire functions of order 0 satisfy the bound, is also well known, as you mentioned. Are you sure that the xi function does not satisfy this bound? is this not an open problem still?
Mar 16 at 22:52 history answered GH from MO CC BY-SA 4.0