02/20/2020, 08:23 PM
(02/20/2020, 06:43 PM)Gottfried Wrote: Hmmm, just to get more familiar to it....
\( z=z^z \)
\( 0=z^z-z \)
\( 0=z \cdot (z^{z-1} - 1) \)
\( 0= f^{\circ 2}(1) \)
where
. \( f(x)=z^x-1 \)
To look for zeros it might be helpful to list zeros of the real- and the imaginary parts separately first.
Interesting.
I prefer to look at it differently or at least used too.
Im not aware of any kind of closed form like lambert W but I have not really tried.
Here is what I did to get 2.86295 + 3.22327 i
Let z^z = z.
Take ln on both sides.
z ln(z) = ln(z) + 2 k pi I
Now if we let k be 1 we get
2.86295 + 3.22327 i = z
And if k = -1 we get
2.86295 - 3.22327 i
And they appear the smallest ones.
That is probably easy to prove though I did not.
I have not considered other ln branches ( on the left side ) , my first guess is they are a invalid solutions ?
——
As for your solution you auto find z = 0 as a solution which is funny since it is invalid ; 0^0 = 1 !
Well at least that is standard. Limit cases and other opinions may differ.
As an explanation we could say you divided by z = 0. If that is satisfactory is another matter.
So as you say we end up with an expression that is a double iteration in disguise.
Consider z^v - 1 = 0
So z^v = 1
This implies v = the period of the function z^t.
Also v = z - 1.
——
We could use Newton iterations to find 2.86295 + 3.22327 i.
Or we have a Taylor series similar to lambert W.
I assume the real part , Imaginary part , norm and argument are all transcendental.
A proof would be nice.
Recall that e^(1/e) and other typical tetration number are also not proven transcendental or even irrational !
I assume there is a way to transform your equations to mine and vice versa without first going back to z^z = z.
Not sure.
I welcome other attempts to solve that equation.
Notice that the real part of ln ln 2.86295 + 3.22327 i is larger than 0 hence it is not on the shell-tron boundary !!
That is remarkable considering its cyclic behavior.
I was thinking about “ its cousin base “
z^z = z
z^^( “ oo “) = z
z^(1/z) = Q
(z^z)^(z^-z) = S
Now
Q^z = z^(z/z) = z = z^z
So Q = z.
It easy to show S = Q = z.
Nothing special
However we also have
T^(1/T) = z
Where T =\= z.
And T within the Shel-tron.
I have to think more about that.
Regards
Tommy1729

