Entropy/Order Coexpansion

Twink (neptune@mars.superlink.net)
Fri, 28 Nov 1997 11:03:47 -0500 (EST)


At 11:24 AM 11/28/97 +0100, Anders Sandberg <asa@nada.kth.se> wrote:
>> Another intriguing possibility in an open universe is that entropy and
>> order can both increase -- in absolute NOT relative amounts.:) This
>> is Layzer's idea. He might be wrong, but we should see if there's
>> anything to his idea.
>
>I think it sounds reasonable. Divide the universe into two sides, and
>use one as an entropy dump. If it gets too "hot", wait for a while
>until it has expanded, and then fump more entropy into it. Of course,
>I suppose this would run into the NIMBY (Not In My Back Yard) effect
>on a cosmic scale.... :-)

No. This is not what I meant, though this too is possible. The dissipative
structure analogy still means that total order plus total entropy is a fixed
sum. Eventually, too, the system would run down.

In the model I am using, one would not need a dump for excess entropy.
Instead, the expanding space itself increases both the order the entropy.
The model is called the expanding phase space idealization. Layzer, to
my knowledge, is the originator of this idea.

To picture what I am talking about imagine a bunch of molecules in a
box. Let's say that at first they are all in one part of the box. After a
certain amount of time, ceterus paribus, they will be spread out -- in
the sense one would be likely to find them anywhere within the box.
This would be an equilibrium state -- or more, accurately, collection of
states. Now imagine that the box can expand faster than the
molecules move. The molecules will never be able to fill the whole
box, in the sense of the first example. One will always be able to
give a rough estimate of where they are.

Now if the universe as a whole behaved like that...

Daniel Ust