(New Brunswick, NJ)
From: Bruno Marchal <[EMAIL PROTECTED]>
To: [EMAIL PROTECTED]
Sent: Wed, 31 Aug 2005 13:08:16 +0200
Subject: Re: subjective reality
On 30 Aug 2005, at 18:01, [EMAIL PROTECTED] wrote:
Speculation for me is not a pejorative term, to begin with. Yes, there
is a sense in which all theories are speculative but
some have ceased to be purely so because either empirical or heuristic
evidence was found in their favor. That is the sense
in which they are no longer considered speculative. So QM, for
example, is no longer called a speculative theory, though
people do speculate a lot around it since it poses some serious
intepretative problems. The Everett version of QM is either
an interpretation of QM or a better theory (let us call it EQM)
depending on whom you ask, and that is actually another
item of speculation, btw. But the people who claim that EQM is a
theory need to come up with feasible empirical tests for
which EQM gives predictions distinct from QM. Until these tests are
proposed and are performed EQM remains a speculative theory!!
My view, as addressed to physicist, is the following. I make it
simpler for reason of clarity.
Unintelligible dualist theory of measurement/observation
comp theory of observation/cognition
The collapse is a speculation on a theory which does not exist, and
which has been invented to make the (isolated, microscopic)
superposition non contagious on the environment. So if you want make
the distinction between speculation and hypothesis, I would say the
"collapse" is far more speculative.
You are probably right about this but I would say it differently:
there is no Quantum Theory of "collapse" though something
quite like that needs to occur to produce the classical world we know.
Anything beyond this is... speculation either way! It
is incorrect to say that "EQM explains collapse" because in EQM there
is no collapse. It is also incorrect to say that EQM
includes COMP for the reasons I already stated to you out of
The problem of comp is that machine cannot know if they are supported
by any computations and it is up to Everett Deutsch etc. to explain why
the quantum computations wins the "observability conditions" on the
(well defined by Church Thesis) collection of all computations. This is
not obvious at all and constitutes the first main result I got.
This I don't quite follow. Sorry! How are "conditions of
observability" defined by CT?
For comp "philosophers of mind" (Alias theoretical cognitive
scientists), the two main result I got can be seen as a "correction" of
the "old" Lucas Penrose argument which try to refute comp by Godel's
If I remember it right this is an argument that aims to show why a
"mathematician" cannot be a "digital computer". Does your
correction make it a better argument? I take it you are saying that it
is correct after all!
>From this I see only a couple of ways out: Either
> 1) your derivation leads you not to QM but to a better physical
theory with testable empirical predictions that falsify
>those of QM, presumably including those that lead to the invalidation
of YD. I would very much like to see that
>theory if you have it!
On my web page you can find all the needed programs to run a theorem
prover of that physics. With some time and training you could perhaps
optimize it and ... refute or confirm comp (admitting quantum logic
operates on nature).
From what has been already derived, some non trivial quantum logical
features did appeared.
I take it that this means you are trying out the route I labelled (1)
or that you think that is the way to go. I am not sure
that "quantum logic operates on nature" because there isn't one but
many "quantum logics" and I am not acquainted
with one that reproduces the quantum formalism with all its quirks.
But what you say above already denotes the use
of some "non-boolean" logic from where I sit.
2) you actually prove (by non-QM means, I assume) that YD is
This is nonsense. Better: with comp it is provably nonsense. (G G*
confusion, for those who knows). It is a key point: if comp is true YD
will never be proved to be implementable. (It is of the type Dt, or
equivalently ~B~t, its truth makes it unprovable).
So it is (1), I guess!
>and that would only require
> that you replace the experience of one human being (may I suggest
yours?) by a digital computer version of the same.
That is the act of faith needed for the comp practitionners. Recall
that for many people such a question will be a weaker one at first,
like should I accept an artificial hyppocampus instead of dying now.
Well the real question will be: should I choose a mac, a pc, or what?
The fact is that comp can justify by itself why it is a act of faith,
and I am not sure it is entirely "comp-polite" to suggest such an
operation to anyone but oneself.
I am glad I was polite enough to suggest you do it to yourself! The
rest of what you say above I don't think I follow...
See I made the switch to the Mac, does that commit my hypocampus to
> (Of course you can always claim that it has already occurred, as you
sometimes suggest and that is cute but just plain silly,
I claim this in the context of comp + OCCAM. Amoeba's
self-duplication, and even the high sexual reproduction of mammals
involved rather clearly digital information processing.
!!! Now you are no longer cute and talking real dirty trash ! I am
turning on my V-chip... (;-)
Check Out the new free AIM(R) Mail -- 2 GB of storage and
industry-leading spam and email virus protection.