>> Or conceivably could an SAS in a classically deterministic universe surmise
>> something like a Level III multiverse, from considerations of the (ontological?)
>> status(es) of terms of alternatives, alternatives of the types studied in logic
>> (e.g. multivalue logic), mathematical theory of probability, & ("pure")
>> mathematical theory of information -- such disciplines as consider structures of
>> alternatives that exhaust the possibilities (a la "p or ~p")?
> I think so; in principle some mathematician could explore the implications of the
> Schrodinger equation (or whatever mathematics turns out to underly our universe),
> just as we play with toy universes such as Conway's Life. Wolfram has spent years
> looking at cellular automata to try to see which ones might produce structure and,
> by implication, life and SAS's. Our tools are not strong enough to get very far
> with this, but in the future we might even simulate universes far enough elong that
> life evolves. And someone in a deterministic universe might eventually simulate our
> own. In fact we could be living there, in a sense.
That makes sense to my addled head.
Another possibility seems to be that an SAS seems fated to describe nature with
quantum mechanics. I found this (excerpted below) while Googling around, it's from
something by list member Russell Standish, also mentioning list member Bruno Marchal.
If it's right, then quantum mechanics is entailed by probability theory combined with
one or another set of not-distinctively-quantum-mechanical ideas, including the idea
of an observer that seems to be more than just a detector, an observer who can relate
various collateral observations together through time ("a psychological experience of
time in order to do the observations"). Anyway, this stuff is apparently old hat
around here! I guess I should have been paying more attention. (It's quite remarkable
to have the schroedinger equation popping out of a combination of probability theory &
an assumption of time experience. I hope I'm not off-base to be reminded of special
relativity's kinematics coming out of a combination of a finite signal speed limit &
assumptions of space, time, & an observer.) If any SAS by combining probability theory
with assumptions of time experience etc will arrive at the schroedinger equation, does
this mean that an SAS can't learn of living in a classically deterministic universe
even if the SAS does live in one? Or does it mean that probability theory plus
observer, time experience, etc. rule out classically deterministic universes in which
observations can take place?
- Ben Udell
A new revolution in physics
Excerpt, regarding the application of the anthropic principle.
So lets try a physicist's approach, which is to assume a few, fairly uncontroversial
things about consciousness, without pretending to know the full story, and see how far
this gets us. Let us assume two things in particular -- that the observer observes by
selecting a partial description from the ensemble, and that there is a psychological
experiennce of time in order to do the observations. If one additionally assumes the
standard axioms of probability theory, and then crank the handle, Schrödinger's
equation pops out, along with most of the structure of Quantum Mechanics!
Surprising as this result may be, two other scientists have independently come to
similar conclusions, each with a slightly different set of starting ingredients. Bruno
Marchal[8,9] started by assuming a particular form of computationalism, as well as
what he calls Arithmetic Platonism (essentially a plenitude structure like above), and
strong form of the Church Turing thesis, and ended up predicting that the observers
knowledge should obey quantum logic. Roy Frieden started with an observer embedded
in 4-D Minkowski space-time, and asked what happens out of game where nature tries to
hide its true reality from the observer. Probability theory enters through the concept
of Fisher Information. In the most general form of the problem, he ends up with the
Klein-Gordon equation, a covariant form of the Schrödinger equation. It is as if, in
the words of Marchal, "Physics is but a branch of (machine) psychology". Even though
each of these efforts are tentative, and the details differ, there does seem to be an
"elephant"' that blind men are discovering.
The observer was seen to be an integral part of physics as a consequence of quantum
mechanics. Do we have the courage to complete the journey and realise that the physics
is defined by the observer?