Dear Bruno,
Let me put to the most salient part of your
reply:
> My feeling Stephen is just that you don't like comp, and I have no
problem with that. Some people takes my
> work to be a beginning of refutation of comp, and perhaps they are
right. I want just illustrate that this is not
> obvious, and the tiny part of physics I have extracted from comp is
for me just very weird (and no more so I
> estimate we are still far from a real reductio ad absurde of
comp).
[SPK]
No, Bruno, I like Comp, I like it a LOT! I
just wish that it had a support that was stronger than the one that you propose
and that in addition to your 1 and 3determinacy that there would be a way to
shift from the Dovetailer view (the "from the outside" view) to the "inside"
view such that some predictiveness would obtain when we are trying to predict,
say the dynamics of some physical system. Otherwise, I claim, your theory is
merely an excursion into computational Scholasticism.
> The weirdness is the many world like feature of any comp reality, the
non computability of the physical
> processes in any reality compatible with comp, and a sort of quantum
logic weaker than usual quantum logic. Is > that so weird? Certainly no more
weird than quantum weirdness.
[SPK]
I am sanguine about QM's "weirdness"!
I see it as implying that there is much more to "Existence" than what we can
experience with our senses. ;)
> If you are really interested in my reasoning, I would dare to
insist going from step to step. If you prefer not
> studying the consequences of comp because you don't have the taste for
it, I will not insist at all. My point is
> just that comp (that is
> 1) there is level of
description of me such that I cannot be aware of functional digital substitution
made at
> that level.
[SPK]
Here we differ as I do not believe that
"digital substitution" is possible, IF such is restricted to UTMs or
equivalents.
> 2) Church
thesis
[SPK]
I have problems with Churches thesis
because it, when taken to its logical conclusion, explicitly requires that
all of the world to be enumerable and a priori specifiable. Peter Wegner, and
others, have argued persuasively, at least for me, that this is simply is not
the case.
> 3) Arithmetical
Realism) > makes the physical science eventually secondary with
respect to number theory/computer science/machine
> psychology/theology whatever we decide to call that fundamental field
...
[SPK]
I have no problem with AR, per say, but see
it as insufficient, since it does not address the "act" of counting, it merely
denotes the list of rules for doing so.
I will go through your thesis step by step
again and see if I can wrestle my prejudices down into some reasonableness.
;)
Kindest regards,
Stephen
Bruno
 Original Message 
Sent: Wednesday, January 28, 2004 9:27
AM
Subject: Re: Is the universe
computable
At 11:57 27/01/04 0500, Stephen Paul King wrote:
Thank you for this post. It gives me a chance to
reintroduce one problem that I have with your model. Like you, I am very
interested in comments from others, as it could very well be that I am
misunderstanding some subtle detail of your
thesis. You
wrote: "... remembering the comp 1indeterminacy, that
is that if you are duplicate into an exemplary at Sidney and another at
Pekin, your actual expectation is indeterminate and can be captured by
some measure, let us say P = 1/2, and this (capital point)
independently of the time chosen for any of each reconstitution (at Pekin
or Sidney), giving that the delays of reconstitution cannot be perceived
(recorded by the first person))." Now my problem is that IF there is any aspect of
perception and/or "observers" that involves a quantum mechanical state there
will be the need to take the "nocloning" theorem into account. For example,
we find in the following paper a discussion of this theorem and its
consequences for teleportation: http://arxiv.org/abs/quantph/0012121
This
is a question people ask me often. But not only the cloning theorem is not a
problem with the comp hyp, but actually it is highly plausible the noncloning
theorem is a direct consequence of comp. Remember that, with comp,
physicalities emerges from an average of an infinity of computationnal
histories: it is a priori hard to imagine how we could clone that. This is no
more amazing than the fact the white rabbit. remember that with comp, from
inside things look a priori not computable. The apparant computability of the
laws of physics is what is in need to be explain with comp. We should perhaps
come back when you have accept all the steps in uda step by
step.
As a possible way to exploit a potential loop hole
in this, I point you to the following: http://www.fi.muni.cz/usr/buzek/mypapers/96pra1844.pdf My main question boils down to this: Does Comp
1determinacy require this duplication to be exact? Is it sufficient that
approximately similar copies could be generated and not exact
duplicates?
It must be exact if the
duplication is done exactly at the right level of substitution (which exits by
hypothesis), and can be approximate if some lower level of duplication is
chosen instead.
How would this affect your ideas about measures,
if at all? I understand
that you are trying to derive QM from Comp and thus might not see the
applicability of my question, but as a reply to this I will again point your
to the various papers that have been written showing that it is impossible
to embed or describe completely a QM system (and its logics) using
only a classical system (and its logics), if that QM system has more that
two Hilbert space dimensions associated. Start with the KochenSpecker
theorem... http://plato.stanford.edu/entries/kochenspecker/
I'm
afraid you make a confusion of level here. What KS showed is that you cannot
put a boolean algebra of values to quantum observable pertaining to some
systems. But this is exactly what comp predict for matter and time notion.
That is why we get quantum logics for the first person verifiable proposition.
Nowhere I pretend to recover a classical logic in which quantum measurement
value can be embedded, quite the contrary with comp classical logic is plainly
false for all verifiable 1notion right at the beginning. BTW, even if KS was
a threat, your argument does not follow because KS is a theorem in quantum
mechanics, and as you say, I just show that the physics is derivable from
comp; if KS is false in the physics derived from comp then KS would indeed be
a problem, but I insist it is not. It is only the apparent computability of
the universe which still remains the miracle.
My feeling Stephen is
just that you don't like comp, and I have no problem with that. Some people
takes my work to be a beginning of refutation of comp, and perhaps they are
right. I want just illustrate that this is not obvious, and the tiny part of
physics I have extracted from comp is for me just very weird (and no more
so I estimate we are still far from a real reductio ad absurde of
comp). The weirdness is the many world like feature of any comp reality,
the non computability of the physical processes in any reality compatible with
comp, and a sort of quantum logic weaker than usual quantum logic. Is that so
weird? Certainly no more weird than quantum weirdness.
If you are
really interested in my reasoning, I would dare to insist going from step to
step. If you prefer not studying the consequences of comp because you don't
have the taste for it, I will not insist at all. My point is just that comp
(that is 1) there is level
of description of me such that I cannot be aware of functional digital
substitution made at that
level. 2) Church
thesis 3) Arithmetical
Realism) makes the physical science eventually secondary with
respect to number theory/computer science/machine
psychology/theology whatever we decide to call that fundamental field ...
Bruno
