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Re: Periodic Table (was exclusion principle which was electrons), and Causation in physics: F=ma



At 13:34 -0500 11/14/03, J. Green wrote:

Granted. I do not doubt things that are proved by experiment (although the
interpretation thereof can be a little dodgy sometimes). I just want to
torture our idea of electrons to the point where I can define what we do
know and what we think. This seems to be getting away from my original
question though. What do we know, and what do we think, about electrons?

Some have been exercised about the word "cause" in this thread. I am
much more concerned about our fast and loose use of the words "proof"
and "prove." I think that we use these words at our own peril,
especially when talking to non-scientists. In fact, we "prove"
nothing, unless it is a statement of pure mathematics. All we can
ever do as scientists is to provide more or less compelling evidence
that the model we are structuring our work around is a reasonable
description of reality. If we make sure that those who hear us talk
understand that we can provide only descriptions of behavior, then it
seems to me that the concern over the use of "cause" pretty much goes
away.

But having said that, let me offer this comment. F=ma is a
mathematical statement. Nothing more. We use it to try to connect our
model of the world to things we can measure. We also know that this
Newtonian model is a very good one as long as we stay away from its
"edges." But who is to say that a more realistic model, even better
than Newton's, might say, "F=ma, but only after a really short period
of time--so short that we can ignore it as long as we stay away from
the edges." Then when we get close to the edges, other models become
more important--QM and relativity--and we have to rethink what we
have been doing with causation in those areas compared to what we did
in the solidly Newtonian regions. I think we will mostly agree that
the third law has some temporal relationship problems when the action
is at a distance, so why shouldn't the second have some. And then we
can agree that, in the context of a model of interactions as fields,
that *all* interactions are actions as a distance, only some
distances are less than others. This seems to me to allow for a
physical model that lets force precede ma, if only by an arbitrarily
short time period, which we can mostly neglect without introducing
any measurable error to our results. When we start talking about
interplanetary or interstellar physics, things are different and our
models must change.

I know that this sort of analysis can lead to an infinite regress,
but I think such effects are pretty far down in the noise, and should
be able to be neglected, at least so far.

Maybe Newtonian physics also needs to be "renormalized."

Hugh
--

Hugh Haskell
<mailto:haskell@ncssm.edu>
<mailto:hhaskell@mindspring.com>

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