Re: The weirdness of the Many Worlds Interpretation

From: Eliezer S. Yudkowsky (sentience@pobox.com)
Date: Thu Jul 03 2003 - 22:00:45 MDT

  • Next message: Brett Paatsch: "Re: push your bike, risk a beating"

    Damien Broderick wrote:
    >
    > On the topic of the MWI, I put forward the following, from a crotchety
    > quantum mechanic on another list who inveighs against relative state
    > interpretations. Here's one nub of his case. I'd like to hear a reasoned
    > defence of MW from someone up to the task:
    >
    > =================
    >
    > Many Universes: originally/more correctly, Relative State Interpretation
    > that fundamentally cannot reproduce the probabilities (Everett introduced
    > the artifact that the branching is probabilistic!). Try out the branching
    > problem.
    > [This refers to a scientist in each state trying to do experiments to test
    > out the predicted probabilities of his QM manyworld. with a state
    > vector that has 2 components with coefficients at psi1*psi1 = 0.9 and the
    > second at psi2*psi2 = 0.1. After three experiments, there would be 11 of the
    > 16 branches in which the scientist(s) would be saying there is less than a
    > 0.05 chance that this quantum mechanics is correct. With time, the percent
    > of universes in which the scientist(s) could still vouch for his(their) QM
    > would approach zero. The chance that we could live in a universe that
    > accepts QM is zero.]

    One explanation is to accept the probabilities as primordial, and prior to
    a frequency interpretation of probability. Various explanations have been
    put forth that try to derive frequencies from amplitudes, including one by
    our good friend Robin Hanson. I think the "standard" answer would be: "I
    don't know why the probabilities go as the squared amplitudes, but it's
    equally a mystery in classical and many-worlds theory - this is not where
    the argument for many-worlds rests." Though it's noteworthy that if Robin
    Hanson is correct, for example, many-worlds *would* be necessary to
    explain the observed frequencies. 

    -- 
Eliezer S. Yudkowsky                          http://singinst.org/
Research Fellow, Singularity Institute for Artificial Intelligence

    This archive was generated by hypermail 2.1.5 : Thu Jul 03 2003 - 22:11:24 MDT