Archive for May, 2008

Entropy – an afternoon’s saga

I started this afternoon somewhat ignorant about the state of thinking and debates concerning entropy and its applicability to economics. Following a link from Michael Tobis’ blog I discovered Herman E Daly, who appears to be a fine thinker. Daly was taught by Nicholas Georgescu-Roegen, whose book “Entropy and Economic Processes” appears to be the seminal work in the application of thermodynamics to economic problems. Let me say at this point that I am sure there is no end of misunderstanding and misapplication of theromodynamics, which is possibly one of the most conceptually difficult fields in physical science, to field outside of physics. Nevertheless, I think there is merit in the attempt.

Reading reviews of GR’s book on amazon, I found a critical review questioning the thermodynamic basis of his work, based on his description of entropy as a measure of disorder. Examining other reviews by the author I discovered a handful of other reviews with exactly the same text, for various other books on environmental economics. This led me to the site of one Frank Lambert, who is on a crusade to stop people thinking about entropy as disorder. I haven’t spent a lot of time reading his articles and so on, but on first inspection he seems to be overly concerned with semantics. That is his concern is that using the word disorder leads to misunderstandings. I’ve found his examples to be a bit weak, and the style to be hectoring.

I still think about entropy qualitatively as disorder – a high entropy system could be in any one of a large number of states, and requires more information to specify the state completely. A low entropy system is in one of fewer possible microstates and this requires less information to specify. For example a regular grid can be specified by three numbers: resolution, x dimension and y dimension. A random arrangement of points requires 2n numbers to specify.

Looks like there’s a bit of a Wikipedia edit war happening over this at the moment. The more I read of the anti-disorderati’s work the more I find it annoying, hectoring, and feel i’m being talked down to. I’ll stick to de Groot and Mazur for my precise definitions of entropy, i think.

I fail to see how “spreading out” and “disorder” are really that different conceptually.

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Dark materials technology

This NS article outlines ideas for using artificial ‘daemons’ as identification. This is such a neat idea, based on what are probably the most literary (by that I mean deep, controversial, brilliantly written) childrens books I’ve ever read.

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