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tangent off of Order being born from disorder?



On Mon, 19 May 1997, Leigh Palmer wrote:


-snipped


The entropy has been shown to be a measure of uncertainty, indeed, and I'm
pleased to see David using that term in preference to the odious "disorder".
It is, however, a measure of uncertainty at *all* scales of length, not only
the submicroscopic. Uncertainty is also related to timescale, by the way, a
fact both David and I have swept under the rug to this point. The
uncertainty in the order of a pack of cards is zero once it has been
isolated from a source of shuffling; that is why the entropy contribution
due to any particualr order is the same: zero. In the limit of incredibly
long times one could fancifully imagine that cards could change places, say
by quantum mechanical tunneling, and that would increase the "uncertainty".
The order of an initially arranged pack would be as uncertain as that of an
initially shuffled pack, however; the entropy increase due to consideration
on an incredibly long time scale would be the same for both cases (and
negligible compared to other terms, including the amplitude of the expected
entropy fluctuations).

-snipped

These comments by Leigh raise a related issue that I've had
trouble understanding. Hawking, and others, state that the directionality
of time is related to entropy; something I don't quite grasp. When Leigh
says 'long timescales' is this referring to time's directionality? If
the uncertainty was not related to timescale, would there be a
directionality?

I tried taking Leigh's example of a deck of cards: Imagine a
universe that consisted of just a deck of cards and a mechanical shuffler
that only shuffled when, say, a radioactive decay occurred within the
mechanism; sort of a Schrodinger's cat type machine. In between shuffles
when the deck's mechanism is idle, is there a directionality to time,
since nothing is contributing to the entropy?

I've got lots of questions here, but no answers.


Mike Monce
Connecticut College