That is almost the correct solution, Hal. If we ask what an observer will make of a random description chosen at random, then you get regular universes with probability exponentially related to the inferred complexity. It is far clearer to see what happen when the observer is a UTM, forcibly terminating programs after a certain number of steps (representing the observer's resource bound) (thus all descriptions are halting programs). Then one obtains a Solomon-Levy distribution or universal prior. However, this argument also works when the observer is not a UTM, but simply a classification device of some kind.

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The WAP has nothing to do with this issue, except inasmuch as universes can only be observed through the eyes of some observer. Again I reiterate that Juergen's resource-bounded "Great Programmer" religion need be nothing but a reflection of our conscious selves stamped upon our observations. Cheers [EMAIL PROTECTED] wrote: > > Juergen writes: > > Some seem to think that the weak anthropic principle explains the > > regularity. The argument goes like this: "Let there be a uniform measure > > on all universe histories, represented as bitstrings. Now take the tiny > > subset of histories in which you appear. Although the measure of this > > subset is tiny, its conditional measure, given your very existence, > > is not: According to the weak anthropic principle, the conditional > > probability of finding yourself in a regular universe compatible with > > your existence equals 1." > > > > But it is essential to see that the weak anthropic principle does not > > have any predictive power at all. It does not tell you anything about > > the future. It cannot explain away futures in which you still exist > > but irregular things happen. Only a nonuniform prior can explain this. > > Isn't this fixed by saying that the uniform measure is not over all > universe histories, as you have it above, but over all programs that > generate universes? Now we have the advantage that short programs > generate more regular universes than long ones, and the WAP grows teeth. > > Hal Finney > ---------------------------------------------------------------------------- Dr. Russell Standish Director High Performance Computing Support Unit, Phone 9385 6967, 8308 3119 (mobile) UNSW SYDNEY 2052 Fax 9385 6965, 0425 253119 (") Australia [EMAIL PROTECTED] Room 2075, Red Centre http://parallel.hpc.unsw.edu.au/rks International prefix +612, Interstate prefix 02 ----------------------------------------------------------------------------