>> 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 fin
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te 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
http://parallel.hpc.unsw.edu.au/rks/docs/revolution/revolution.html
Excerpt, regarding the application of the anthropic principle.
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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 experience 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 d
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ffer, 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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Received on Fri Nov 14 2003 - 17:56:42 PST