Comment on Polarized gamma rays and manifest infinity

Sun, 31 Jul 2011 02:01:06 GMT

(To side step the issue of how to make sense of probabilities over observations given anthropic-reasoning problems, I'll assume UDT and just talk about priors on universes instead.)

I'm still torn between thinking that the universe must follow a simplicity prior in some objective sense and there might be a way to find out what that objective prior is, and the idea that a prior is just a way of specifying how much we care about one universe versus another. (See the third and fourth bullet points in What Are Probabilities, Anyway?)

If it's the former, then any notion of simplicity that we currently have might be wrong in the sense of not matching up with the objective "reality fluid". If the latter, a notion of simplicity might be wrong in the sense of not reflecting how much we actually care about one universe versus another. In either case, it seems unlikely that any specific notion of simplicity, based on a model of computation (e.g., universal Turing machine) that was chosen because it happens to be useful for reasoning about practical computers, would turn out to be right.

Does that answer your question?

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