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Article 6085 of comp.ai.philosophy:
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>From: daryl@oracorp.com (Daryl McCullough)
Newsgroups: comp.ai.philosophy
Subject: Re: Hypothesis: I am a Transducer (Formerly "Virtual Grounding")
Message-ID: <1992Jun4.142045.1608@oracorp.com>
Date: 4 Jun 92 14:20:45 GMT
Article-I.D.: oracorp.1992Jun4.142045.1608
Organization: ORA Corporation
Lines: 66

holmes@opal.idbsu.edu (Randall Holmes) writes:

>I think that "hidden variables" is the correct explanation of the
>physical reality (which is not to say that I am disputing QM
>predictions).  I think that particles are real (they leave little
>spots on emulsions; how real can you get?) but that the "waves" are
>not. The wave side of the duality is (I think) a mathematical
>representation of what information we are allowed to have about the
>real particles (restrictions imposed by the quantum of action); and we
>actually do "observe" the effects of waves via statistical
>distribution of observations of _particles_ (waves are arguably never
>directly observed!)  However, the behaviour of the waves is so elegant
>that we "reify" them.

Hi, Randall! I don't know if you remember me, but we were in a set
theory course together at Cornell. We discussed your research into
NFU quite a bit.

Anyway, while I have enjoyed your comments about AI, I have to
disagree with your discussion of quantum mechanics. I don't think that
there is a consistent interpretation of a wave function as a
measurement of our information about the location of a particle. The
main difficulty with such an interpretation is that there is no role
for the phase of the wave function in such an interpretation, and the
phase is crucial for such things as interference effects.

I tend to believe that *particles* are the reification of terms in an
expansion of the wave function. In quantum field theory, the reality
of particles is even more in question. The fundamental quantity seems
to be the field (the analog of the wave function). Particles are seen
to be excitations in the fields, not entities in their own right.

>What is necessary to make progress is to figure out why information
>about particles (the actual reality) is restricted in this way.
>This is hard work; we will make no progress in this direction as
>long as we continue to take the easy course of treating
>the waves as an independent physical reality (an attractive
>explanation which probably should have been avoided).

Once again, I disagree strongly. There is no reason (that I know of)
to doubt that waves are part of physical reality. The so-called
"collapse of the wave function" tends to make people think of the
parallel with ordinary probability: When we flip a coin in the dark,
we can describe the situation as "Heads, with 50% probability, and
tails, with 50% probability." However, when we turn on the light,
the coin seems to "collapse" into a define state, either heads or
tails. Obviously, in this case, there really is no collapse; the
coin was either heads or tails before we turned on the light, we
just didn't know which.

Discussion of quantum mechanics, without the mathematics of
interference, might lead people to think that the situation is
comparable to the case with flipping a coin. The particle really has a
position, we just don't know what it is. When we observe the particle,
the collapse of the wave function is simply a change in our knowledge.
What's the big deal?

However, the mathematics does not support this interpretation, because
of interference effects between alternatives. There is a testable
difference between the following two situations:

   1. The particle either has spin-up, or spin-down, we just don't know
      which.

   2. The particle is in a superposition of a spin-up state and a spin-down
      state.


