virus: Entropy

Eric Boyd (6ceb3@qlink.queensu.ca)
Sat, 6 Feb 1999 15:02:47 -0500

Hi,

Tim Rhodes <proftim@speakeasy.org>:

<<
Or they don't perceive a need to change. What was that first law of thermodynamics again?
>>

Well, the Kelvin-Planck definition is that "It is impossible for any system to operate in a thermodynamic cycle and deliver a net amount of work to it's surroundings while recieving energy by heat transfer from a single thermal reservoir." On can easily modify this (drawing system schematics, etc) to the Clausius statement: "It is impossible for any system to operate in such a way that the soul result would be an energy transfer by heat from a cooler body to a hotter body."[1]

Interestingly, entropy itself is not part of the second law; entropy instead is a mathematical tool designed to make working with the second law easier. If anybody is interested in the mathematical formulation of the second law (the *equation*), let me know and I'll write up a post describing it.

That aside, there any many common "lay" versions of the second law, and one in particular (which I think originally came from a political intrepretation, but has now out-grown that), which states that in a closed system, order decreases (or remains the same).

If one removes the "closed system", and then accepts that *evolution* is an order increasing system[2], then one can maintain that evolution violates the second law. However, one could equally, at that point, maintain that life itself (e.g. any living being) violates the second law, clearly making this a non-sense intrepretation.

I have my own personal[3] intrepretation of evolution and entropy. As food for thought, I will merely point out that entropy can be seen as a force which seeks to make things stable that is, it wants to bring the universe into a situation where only stable things exist (e.g the so-called heat death of the universe is a result of maximum entropy). Evolution, on the same hand, is a process which attempts to make biological (or whatever the substrate is) objects stable in their environments i.e., adapted to survival. Increasing, I see both evolution and entropy as one and the same force. The axiom underlying both is that stable things survive.

ERiC

[1] Fundamentals of Engineering Thermodynamics, third edition, Michael J Moran and Howard N. Shapiro., pg 170

[2] Which of course is dubious itself. Is a human any more "ordered" than the primates from which it evolved?

[3] That is, personally derived. As far as I can tell, my intrepretation of entropy accuratly reflects the physics as well as the mathematics of entropy. Not that "stable" things are often less ordered than unstable ones, but not always.