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Article 3865 of comp.ai.philosophy:
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>From: weemba@libra.wistar.upenn.edu (Matthew P Wiener)
Newsgroups: comp.ai.philosophy
Subject: Re: QM nonsense
Message-ID: <66636@netnews.upenn.edu>
Date: 19 Feb 92 15:12:38 GMT
References: <66422@netnews.upenn.edu> <427@tdatirv.UUCP>
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Reply-To: weemba@libra.wistar.upenn.edu (Matthew P Wiener)
Organization: The Wistar Institute of Anatomy and Biology
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In-reply-to: sarima@tdatirv.UUCP (Stanley Friesen)

In article <427@tdatirv.UUCP>, sarima@tdatirv (Stanley Friesen) writes:
>|All the experiment can do is emphasize experimentally just how weird the
>|extreme view is.  Schroedinger's cat was the first theoretical description,
>|and the debate is still alive.

>It is true that this is a *possible* interpretation, but I have this problem
>with it:

You are not the only one.  When I say "the debate is still alive", that's
just what I mean.

>It posits that the experimental apparatus is in a superposed state that is
>*theoretically* *indistinguishable* from the non-superposed state in *all*
>*conceivable* experiments.

As far as we know, yes.  To many--like Schroedinger or Penrose--this is
grounds for saying that QM is flawed.

>At this point I say - positing a superposition of states serves no theoretical
>purpose, and is no longer required by any prediction of the theory, so throw
>it out as a needless complication.

And at this point others say that positing a wave function collapse before
the human observer serves no purpose either, and it is no longer required
by any prediction, etc.

The debate is still alive for a very good reason.

>				     "A difference that makes no difference
>is no difference" - the superposition states of quantum particles are
>*observable*, at least indirectly, through such things as self-interference 
>patterns and 'watched-pot' effects.

And how indirect are you willing to go?  Do you have a theory for saying
which items collapse wave functions and which don't?

>In short, as long as superpositons have observable consequences, I am forced
>to accept them, where they do not, I see no reason to believe they exist.

No, you choose to accept them, and from there you duck certain hard
questions.  There are numerous interpretations out there, and each one
has its packet of strangeness and difficulty.  They differ from each
other wherein these packets lie.  If you only ask one question, it's
easy to pick a winner.  But like I titled a previous posting, "Occam's
barber had many customers."
-- 
-Matthew P Wiener (weemba@libra.wistar.upenn.edu)


