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Article 6036 of comp.ai.philosophy:
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>From: clarke@acme.ucf.edu (Thomas Clarke)
Newsgroups: comp.ai.philosophy
Subject: Re: Quantum mechanics (no AI here, sorry)
Message-ID: <1992Jun2.125347.18625@cs.ucf.edu>
Date: 2 Jun 92 12:53:47 GMT
References: <1992Jun01.234940.40210@spss.com>
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In article <1992Jun01.234940.40210@spss.com>  writes:
> It sounds like you're thinking there is a "real" state of the universe--
> or, to put it into more concrete terms, an electron does have a definite
> position and momentum-- only we can't find out what they are.  Heisenberg
> actually goes further than this: there is no "real" state of the universe;
> you can't find out the electron's definite position and momentum because
> it doesn't have one.
> 
> Common sense rebels at this; but common sense needs to spend more time
> thinking about waves.  Any wave can be built up out of superimposed simple
> waveforms-- e.g. sine waves or impulse waves.  A particular wave might
> be built up out of just 3 sine waves, in which case it will take a whole
> bunch of impulse waves to synthesize it.  Or if it only takes a few impulse
> waves, the analysis into sine waves will be very complex.  You can't have
> a wave that's extremely simple in both sine-wave terms and impulse-wave
> terms, because these are opposite types of waveforms.
> 
> This isn't just an analogy-- it's the reason behind the "uncertainty
> principle."  Position and momentum are different aspects of the quantum
> wavefunction of a particle; you can't get both at the same time for the
> same reason you can't analyze a wave into simple superimpositions of
> opposite waveforms.
> 
> Now, your idea that the universe does have "real states" even if we can't
> (yet?) observe them is not new; such "hidden variable" theories can be
> built which are compatible with quantum facts.  However, it's been
> pretty well established that such theories can't explain the facts without
> recourse to faster-than-light signalling.
> 
> For further reading, I'd recommend Richard Feynman's _QED_, Nick Herbert's
> _Quantum Reality_, and J.C. Polkinghorne's _The Quantum World_.

Waves aren't the whole picture either.  Life would be simpler if it
were!  Energy insists on being transferred only in discrete quanta of
size Planck's constant times frequency.  I once came across an analogy:
It's as if when ocean waves hit the beach, instead of washing up onto the
sand, all of sudden frogs were to leap out, the number of frogs being
determined by the size of the wave.  Catch a bunch of frogs and they turn 
back into waves in your bait bucket.


--
Thomas Clarke
Institute for Simulation and Training, University of Central FL
12424 Research Parkway, Suite 300, Orlando, FL 32826
(407)658-5030, FAX: (407)658-5059, clarke@acme.ucf.edu


