[pf] entropy.

by David MacClement

11 December 2000 19:25 UTC

· I've been aware for several decades that a major part of the answer to
that standard question about life, the universe and everything, is entropy.

· More specifically, changes in entropy: without a system that operates to
use energy and materials to produce order, entropy _will_ increase. Entropy
has many descriptions, the most indisputable being the mathematical one
(which I've forgotten), but it is basically a measure of disorder.

· Living things, including cells, work to maintain themselves against
breakup, and to produce more of the same or very similar living things;
this production of an organised organism results in a reduction of entropy:
the randomly placed molecules before (say) a new cell is produced are put
in specific locations (part of the mitochondria, the cell wall, etc.) -
they are now ordered after having been mixed up with all sorts of other stuff.

· In the past I've unquestioningly accepted that another example of
increasing entropy (corresponding to the decay of an organism) is the
extraction of minerals and other resources that have been concentrated in
coal seams, diamond mines, oil fields, iron mountains and so on, then used
by humans and after use the original atoms are spread far and wide (unless
the materials are mostly recycled). It's clearly why I'm against humans
putting huge amounts of carbon dioxide into the atmosphere.

· For me this has been the main reason I've been concerned about "running
out of resources"; not that there will be less and less availability of
those resources for human use, but that humans are actively increasing the
entropy of the world (which life goes against). I don't need a god to tell
me what's good and bad; for me, actively increasing entropy is bad,
decreasing entropy is good - in a general sense, but often specifically too.

· I'm thinking about this on this sunny early-summer Tuesday morning
because I've started thinking about the cream that settles-out on the
inside of our full-cream organic milk cartons.
  Originally it's mixed thoroughly with the rest of the milk (the
skim-milk), but after days in our fridge, especially if I don't turn the
carton, there's a quite thick layer which I try to remove before it bothers
someone else. (With my very low blood pressure and excellent health, I use
it as part of my normal food.) The point is, in this context, that certain
molecules have become concentrated in certain places, which I interpret as
an increase in order, in the same way that a mineral has been concentrated
at certain places in the rocks under the earth's surface.

· Here are two examples where there appears to me to be no use of energy to
produce this increase in order (decrease in entropy), and little except
gravity and perhaps a temperature-gradient to make the separation occur in
a particular place. Nothing with its own organisation, as in the mitosis of
a cell, to /do/ the organising, to reduce entropy.

· I'm puzzled. Any comments?

David.