Hi Julian,

Julian Suggate wrote:

I've not posted to this group previously, but I can't resist this one ;^)

Hal Finney wrote:

Matt King writes:

I should point out that there does remain a vanishingly small possibility that we could be in one of the extremely 'magical' universes where both macroscopic and microscopic laws of physics are skewed in a mutually consistent way, however given the tiny probability of this being the case I think it is quite safe to ignore it.

That seems rather extreme, because the probablity that we are in a
"regular" "magical" universe is already vanishingly small and we would
truly be safe in ignoring it. Even the probability of observing a single
large scale violation of the laws of probability is vanishingly small.
("Magical" universes suffer from repeated large-scale

According to *our* laws of probability, that is.

But how can you make recourse to our laws of probability if there are infinitely many universes which have different laws?

Isn't Frederico's original proposition based on assuming infinite variability and duplication of probability theory amongst all level 1 universes?

So I would think that taking the assumption onboard means you cannot argue we are 'probably' in one of the more common universes... since 'probably' changes from universe to universe.

Correct me if I'm wrong!

...However, the laws of probability themselves are not physical but mathematical in origin. Even in a 'magical' universe, you would still have the same basic laws of probability (Gaussian distributions and the like) as this is just math, and math is truly universal. For example, if you make the assumption that a die is evenly weighted, you will get the same statistical models about dice throwing whichever universe you happen to be in. What would be different in a 'magical' universe is that these laws of probability would not seem to apply to a particular physical system - or much more rarely - to any particular physical system, so you could be in a 'magical' universe where although your statistical model predicts differently, you always throw double six, for instance.

The fact that physical systems in our universe do obey probabilistic laws like thermodynamics is therefore extremely good evidence that we are not in such a 'magical' universe.

Hope this helps,

Matt.

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When God plays dice with the Universe, He throws every number at once...

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