open problems survey
#21
As we're posting our own conjectures here, I thought I'd add mine to this list.

In William Paulsen and Samuel Cowgill's paper; they outline the following uniqueness condition:

\(
F(z)\,\,\text{is holomorphic on}\,\,\mathbb{C}/(-\infty,-2]\\
F(0) = 1\\
F(\overline{z}) = \overline{F(z)}\\
\forall x \in \mathbb{R}\, \,\lim_{y\to\infty} F(x+iy) = L\\
\text{where}\,L\,\text{is the fixed point of}\, \exp\, \text{with minimal imaginary argument}\\
F(z+1) = e^{F(z)}\\
\text{Then necessarily,}\\
F(z)\,\,\text{is Kneser's Tetration}\\
\)

Which they prove, as I believe, completely satisfactorily (Kouznetzov seemed to have doubts).

This question is in two parts:

A). Does there exist a tetration function \( G \) which has all these properties except,

\(
\lim_{y\to\infty} G(x+iy) = \infty\\
\)

B.) Does it satisfy the same uniqueness condition that William Paulsen and Samuel Cowgill proposed? (Albeit, with the different behaviour \( \Im(z) = \infty \)).


For A.)--See related threads about the beta method (https://math.eretrandre.org/tetrationfor...p?tid=1314, https://math.eretrandre.org/tetrationfor...p?tid=1334), which seems to point to the beta method not being kneser (I've proved the beta-method converges, but not that it isn't still Kneser's method). But numbers clearly show a discrepancy...

For B.) I don't know at all, but there's a hunch--by looking at Tommy's Gaussian method and the beta method they seem to be one and the same. See: https://math.eretrandre.org/tetrationfor...p?tid=1339 . Furthermore, this conjecture was made by how well different manners of coding the beta method all still gave the same numbers; when I would use different asymptotic shortcuts the same function appears.

I believe I can sketch a proof of A.), but I'd need oversight before it ever became a proof. As for B.), I can't even think of a line of attack.

Regards, James
Reply


Messages In This Thread
open problems survey - by bo198214 - 05/17/2008, 10:03 AM
Exponential Factorial, TPID 2 - by andydude - 05/26/2008, 03:24 PM
Existence of bounded b^z TPID 4 - by bo198214 - 10/08/2008, 04:22 PM
A conjecture on bounds. TPID 7 - by andydude - 10/23/2009, 05:27 AM
Logarithm reciprocal TPID 9 - by bo198214 - 07/20/2010, 05:50 AM
RE: open problems survey - by nuninho1980 - 10/31/2010, 09:50 PM
Tommy's conjecture TPID 16 - by tommy1729 - 06/07/2014, 10:44 PM
The third super-root TPID 18 - by andydude - 12/25/2015, 06:16 AM
RE: open problems survey - by JmsNxn - 08/23/2021, 11:54 PM
RE: open problems survey - by Gottfried - 07/04/2022, 11:10 AM
RE: open problems survey - by tommy1729 - 07/04/2022, 01:12 PM
RE: open problems survey - by Gottfried - 07/04/2022, 01:19 PM
RE: open problems survey - by Catullus - 07/12/2022, 03:22 AM
RE: open problems survey - by JmsNxn - 07/12/2022, 05:39 AM
RE: open problems survey - by Catullus - 11/01/2022, 06:33 AM
RE: open problems survey - by Leo.W - 08/10/2022, 01:23 PM
RE: open problems survey - by tommy1729 - 08/12/2022, 01:28 AM
RE: open problems survey - by Leo.W - 08/12/2022, 05:26 AM
RE: open problems survey - by Catullus - 12/22/2022, 06:37 AM

Possibly Related Threads…
Thread Author Replies Views Last Post
  open problems / Discussion Gottfried 8 25,261 06/26/2008, 07:20 PM
Last Post: bo198214



Users browsing this thread: 2 Guest(s)