>> 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[15]!

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[7] 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?

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