
2nd Law of Thermodynamics Doesn't Prohibit a Decrease of Entropy - smaslennikov
http://thinkinghard.com/blog/SecondLawDoesntProhibitEntropyDecrease.html
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gdavisson
This article starts from a completely wrong premise: a beneficial mutation is
_not_ a decrease of entropy in a closed system. There's no closed system
involved.

Organisms are not thermodynamically closed, because they take in both material
and some sort of free energy (whether together in the form of food, or
separately as in water, air, sunlight, etc), and also emit both waste heat and
waste material. Organisms don't even have any (nontrivial) closed subsystems.

Most of the interesting things organisms do -- grow, reproduce, evolve
progressively, maintain their states -- run counter to the general
thermodynamic tendency for systems to approach equilibrium. This does not
violate the second law of thermodynamics because organisms' inputs have lower
entropy (and higher free energy) than their outputs. As long as there's more
entropy leaving than coming in, internal entropy decrease is allowed by the
second law (up to the difference between influx and efflux).

(Actually, I'm cheating a little bit here. Entropy is a property of things,
not a thing itself, so talking about it entering or leaving isn't really
right. But it _acts_ like a thing, and entropy flux is (usually) well-defined
and acts as you'd expect flow of a physical thing to work.)

(BTW, there's a bit of inconsistent terminology here. Physicists call systems
that don't exchange either energy or matter with their surroundings "closed".
Chemists call those systems "isolated", and use "closed" for systems that
exchange energy but not matter. Which physicists call "open". Yeesh. Anyway,
this version of the second law applies to physicist-closed/chemist-isloated
systems. Organisms exchange both energy and matter, so they're "open" in
either terminology.)

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Gibbon1
> Organisms are not thermodynamically closed

Organisms are thermodynamic machines.

