Thermodynamics and Evolution
Back in 1984, John W. Patterson contributed an essay called “Thermodynamics and Evolution” to a volume of scientific responses to creationism.
Creationists have claimed that the second law of thermodynamics (”The Entropy Inventory of the World Tends to a Maximum”) conflicts with evolution. How could evolution to higher, more ordered, forms of life be possible when the universe tends towards disorder? The answer is an elegant one:
1. Yes, there are many spontaneous “downhill” (towards disorder) processes going on all the time in the universe. The universe, as a whole, is a closed system to which the second law applies.
2. These downhill processes provide the energy fluxes/differences that prompt uphill (towards order) developments.
3. As long as the downhill flows exceed — overall — the constructive processes of evolution, the second law is not violated. Entropy increases, on the whole.
4. But inside open systems like the earth's biosphere (or an ideally end-to-end internet), order is increasing.
5. It turns out that energy and entropy are subject to being transferred from place to place in the universe. Remember, although the universe as a whole is an isolated system, many things inside it are not. No organism is an isolated system.
6. Patterson uses a metaphorical walled-off courtyard to represent the universe. It is open to the sky, and snow is falling. The snowfall represents the entropy inventory. Within the courtyard, however, wind can create deep local furrows — these are examples of increasing order in open systems. That entropy decrease can occur as long as it is coupled with compensating (or overcompensating) entropy increases nearby.
7. Localized entropy reduction is very common. We get “order for free” all the time, as long as the system in question is open to outside energy and is at a critical state (what Prigogine calls a “dissipative” system). These dissipative systems have had heat or other forms of energy applied to them, have become unstable, and have therefore undergone a phase change into highly ordered configurations.
8. All of these dissipative systems have to do something with their excess entropy. A dishwasher puts out heat; so does a laptop. Inside, order reigns — as long as more entropy is expelled than is ingested.
9. This local order emerges BECAUSE the outside area is becoming increasingly disorganized. The vast majority of mutations are discarded or disappear. Meanwhile, the energy requirements of living systems are derived from all of these things flowing “downhill” — towards disorder. As long as the dominant tendency is downhill, creating tensions and differences that provide energy, small uphill steps are made possible by the feedback loops in dissipative systems.
10. Patterson notes that “entropy” has been a useful term for creationists to use (evolution violates the rules of entropy!) because no one understands what it means. Indeed, Claude Shannon was advised by Jon Von Neumann to call his “uncertainty function” by the name “entropy.” Von Neumann said, “No one knows what entropy really is, so in a debate you will always have the advantage.”
Here is Patterson's conclusion:
“In reality, … the 'uphill' processes associated with life not only are compatible with entropy and the second law, but actually depend on them for the energy fluxes off of which they feed. Numerous other kinds of backward processes in simpler, nonliving systems also proceed in this way, and do so in complete accord with the second law.”
This all ties to internet governance. A sufficiently open net will tend towards order, not chaos — and will do so on its own, with no external pilot.
(Thanks to Seth Schoen for the pointer.)
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After hearing that evolution contradicted the second law of thermodynamics, I always wondered how I was able to so handily defy the laws of the universe whenever I managed to organize anything at all (desk, piles of clothing, pez dispensers, etc). Prior successes in the defeat of the incontrovertible law of Entropy were beginning to lead me to think I could as easily conquer other basic laws of physics as well, like gravity. Just like my hero God-Man does.
While reading this I envisioned entropy as water, pouring into dissipative systems, which use the energy, convert it into extropy, harnessing it to build themselves up.
It's as if order orders itself in clusters, sucking the unorder out of the surrounding area. It is similar to the way galaxies cluster, leaving vast spaces of nothing(?) inbetween them.
Not only do we live on a literal gravity well (the earth), we are (metaphorical) gravity wells of a sort, attracting and absorbing the energy of entropy.
I shall shut up now. Caffeine and lack of sleep has blown a hole in my brain and entropy is seeping into my thought processes.