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From: augeri@regina.DEC (Mike Augeri)
Newsgroups: net.physics
Subject: Heisenberg Uncertainty Principle
Message-ID: <3506@decwrl.UUCP>
Date: Wed, 7-Aug-85 21:43:59 EDT
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Posted: Wed Aug  7 21:43:59 1985
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I imagine that these questions probably have been asked before, but I have
not seen them during the time that I have been reading net.physics, so
here goes.  I can hear the experts saying "Oh boy, here we go again with
some more dumb questions."

In over-simplified terms Heisenberg's Uncertainty Principle says that we
cannot know the simultaneous position and momentum of an individual
elementary particle with unlimited accuracy.  Yet, we are able to
determine the simultaneous position and momentum of conglomerations of
these elementary particles.  That is, I can determine the position and
momentum of my desk to a degree of accuracy limited only by the resolution
of the measuring equipment I use, whereas the Uncertainty Principle says
that no matter how accurate my measuring equipment, when it comes to the
individual particles making up the desk, it is fundamentally impossible to
even make the observation.

What is different about the individual particles and groups of particles?
Is it strictly a case of the measurement process itself disturbing the
individual particle, or is something else going on here?  For example, it
seems to me that if it is simply a matter of the measurement process
disturbing the particles we are trying to measure, then we just have to
find a measurement process that uses small enough particles so that they
won't disturb the particles we are trying to measure.  I am not saying
that such particles exist.  But in my opinion saying that "in principle,
it is impossible to measure the simultaneous position and momentum of a
particle" is quite different than saying that "the means to measure the
simultaneous position and momentum of a particle does not exist".  The net
result is the same, but the statements are different.

	Mike Augeri, DEC, Maynard MA USA