From: samodena@csemail.cropsci.ncsu.edu (S. A. Modena)
Subject: Re: Trouble at the 0K corral!
Keywords: WE ARE IN TROUBLE FOLKS!!!!!!
Organization: Crop Science Dept., NCSU, Raleigh, NC 27695-7620
Distribution: bionet
Date: Thu, 12 Nov 1992 10:06:15 GMT


The whole of Tom's article is there, for those who need it. Reading the
comments will surfice.

In article <BxKGtu.6BF@ncifcrf.gov> toms@fcs260c2.ncifcrf.gov (Tom Schneider) writes:
>In article <1992Nov11.123056.16262@ncsu.edu>
>samodena@csemail.cropsci.ncsu.edu (S. A. Modena) writes:
>
>>Entropy is a measure of a DYNAMIC process/system; no dynamics? ==> H(x) = 0!
>>Zero Kelvin BY DEFINITION == NO DYNAMICS == ENTROPY FIGURE OF ZERO!!!!
>
>Check out page 39 of Waldram (@book{Waldram1985, author = "J. R. Waldram",
>title = "The Theory of Thermodynamics.", publisher = "Cambridge University
>Press", address = "Cambridge.", year = "1985"}).  He defines the (statistical)
>entropy based on the probabilities of the system, whether or not it's at
                      ^^^^^^^^^^^^^
                      this is a key word, the meaning of which
                      is synonymous with dynamic system.

>equilibrium.  In fact, he is being very careful with the definition to allow
^^^^^^^^^^^^
this is a key word, the meaning
of which is synonymous with dynamic system.

>non-equilibrium situations.  Basically, if you can get the probabilities, you
^^^^^^^^^^^^^^^^
this is a key word, the meaning of
which is synonymous with dynamic system.

There are at least two varieties of dynaimc systems.  The equilibium
system has migrants or transitions such that each state appears to
have a steady population (probability) at a frame smoothing beyond a couple
of time-constants (if you don't understand time-contant; substitute
"time long enough that brownian movement vectors sum to zero ).
Non-equilibrium systems are defined as NOT( equilibrium system).


>can use his definition.  However, one still must distinguish carefully about
>what is meant by 'equilibrium'.  Steve, I presume you are referring to the
                 
We most certainly must be careful about what is meant by 'equilibrium":
that is a reminder to mathemateticians and theoretical physicists
who must begin from a careful definition of these terms....supposedly.

>microscopic changes that occur at higher temperatures in "equilibrium" systems;
>that is a kind of 'dynamics'.  Surely we must all agree that at zero Kelvin
>there could be alternative configurations frozen in?  Ahh but now we have a
>contradiction!  For zero K is (apparently) defined only for a perfect crystal!
>So that means that a substance could lose all heat energy (which is impossible
>to do, but we'll imagine it anyway...) but have alternative configurations.  If
>zero K is defined only for a perfect crystal, then what temperature is the
>imperfect crystal that is in thermal equilibrium with the perfect crystal?
>Seems to me that they must have the same temperature!  Anybody see a way out of
>this puzzle?

Well, the way is just the one I took in another post: will the
mathematicians/physicists/chemists please state the axiomatic definition of
ZERO Kelvin non-jargonistically?     Is the phrase ABSOLUTE ZERO a
misnomer?

>
>> I repeat it: at Absolute Zero, there can be no
>>H(before)-H(after) calculation, therefore this is a B.S. line of discussion.
>
>That was my point earlier, though I didn't say it so graphically...  (B.S.
>must stand for "a Bit Shady", right?)  On the other hand, if one compares the

No, I definitely mean BLATANTLY SHAKEY.  :^)  Which is espaniol for
Bull Taco.

>imperfect to the perfect crystal at the same temperatures but different
>configurations, there will be a definite positive value for R = H(before) -
>H(after) ...

Notice what you did Tom.  You said compare one crystal with another.

Let's get to the core of the problem.

Thermo seems to be based on relative comparisons: compare state 1 with
state 2 and forget about the path traveled.  This is an immensely
practical approach to real world problems.  It is also PURELY
arithmetic.

But the conversation devolved to a discussion of an ABSOLUTE, PRIMAL
state of the Universe: what does ZERO Kelvin mean in the material
Universe, rather what does ZERO Kelvin mean as a mathematical axiom
existing only in the imagination of humans?  Note the switch from
arithmetic to mathematic; relative to absolute; attainable to unattainable;
real to virtual.

>
>>Will someone please email me some 2-penny nails to chew on, I'm fresh out
>>and having a fidget fit.  :^)
>
>Sorry, I only have one left over, the rest are in the corral:
>
>      _
>     / \
>     |O|
>     |K|___________________________
>     |  ___________________________>
>     |O|
>     |K|
>     \_/


Thank you for the virtual gnawing nail.  :^) 
(Munch) Aaahhhh! That's was virtually satisfying!  (Burp)

>
>
>  Tom Schneider
>  toms@ncifcrf.gov

Steve 

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