# Re: Quantum Time Travel

From: Russell Standish <R.Standish.domain.name.hidden>
Date: Wed, 19 Apr 2000 10:22:10 +1000 (EST)

Naturally, what I've said shouldn't be contraversial. Perhaps the next
statement will. If you've read my Occam paper, you will see that an
absolute measure on the AUH is not required to resolve the White
Rabbit problem. The conditional measure based on some definition of
observer is all that is required. This is just as well, as there
appears to problems with defining an absolute universal prior.

When you write absolute measure, I tend to take this as the measure of
the multiverse, given some initial condition. Given some initial
condition \psi_0, and a Hamiltonian H, the measure of any given
quantum history is well defined. The observer defines the form of H,
and to a slightly lesser extent the initial condition (the Anthropic
Principle). If you were to average over all H's, and all initial
conditions, one must surely end up with a measure distribution devoid
of information, and probably something like the uniform distribution
(although I haven't worked through the maths to see if this is
actually what happens, or even if the procedure is possible).

Cheers

>
> --- Russell Standish <R.Standish.domain.name.hidden> wrote:
> > In order to obtain any measure distribution that
> > differs from the uniform one (ie contains
> > information), one must have a selection from
> > the plenitude (or the multiverse if we're talking
> > observer, and can be different for different
> > observers.
>
> I wouldn't call the measure distribution "uniform"
> even for the AUH, just as the TM universal string
> distribution (outputs of a random program; it's not
> computable) is not the same as the uniform
> distribution (random bitstring). The measure
> distribution for the AUH is quite nontrivial even if
> (in principle) it contains no information.
> That said it just sounds like you're talking about
> a conditional effective probability, conditional on
> some definition of "the observer". So I can't argue
> with that because you haven't said anything
> controversial above :(
>
> =====
> - - - - - - -
> Jacques Mallah (jackmallah.domain.name.hidden)
> Physicist / Many Worlder / Devil's Advocate
> "I know what no one else knows" - 'Runaway Train', Soul Asylum
> My URL: http://hammer.prohosting.com/~mathmind/
>
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>

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Dr. Russell Standish Director
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Received on Tue Apr 18 2000 - 17:18:30 PDT

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