No I am not claiming cells are closed systems and does it really matter.
The Harvard scientist, John Ross, comments:
...there are no known violations of the second law of thermodynamics. Ordinarily the second law is stated for isolated systems, but the second law applies equally well to open systems. ...there is somehow associated with the field of far-from-equilibrium phenomena the notion that the second law of thermodynamics fails for such systems. It is important to make sure that this error does not perpetuate itself.6
Does Entropy Contradict Evolution?
Creationists who cite the entropy principle against the evolutionary philosophy are, time and again, dismissed as either ignorant of thermodynamics or dishonest in their use of the second law.
Yeah, that pretty much covers it.
In an open system (such as the earth receiving an influx of heat energy from the sun), the entropy always tends to increase
Which doesn't stop cells, or complex organisms, from getting more complex or evolving.
Your comment is predictable.
Does Entropy Contradict Evolution?
by Henry Morris, Ph.D. *
The popular syndicated columnist, Sydney Harris, recently commented on the evolution/entropy conflict as follows:
There is a factor called "entropy" in physics, indicating that the whole universe of matter is running down, and ultimately will reduce itself to uniform chaos. This follows from the Second Law of Thermodynamics, which seems about as basic and unquestionable to modern scientific minds as any truth can be. At the same time that this is happening on the physical level of existence, something quite different seems to be happening on the biological level: structure and species are becoming more complex, more sophisticated, more organized, with higher degrees of performance and consciousness.1
As Harris points out, the law of increasing entropy is a universal law of decreasing complexity, whereas evolution is supposed to be a universal law of increasing complexity. Creationists have been pointing out this serious contradiction for years, and it is encouraging that at least some evolutionists (such as Harris) are beginning to be aware of it.
Does Entropy Contradict Evolution?
Why does the law of increasing entropy, a law arising from statistics of many particles, underpin modern physics?
As far as I interpret it, the law of ever increasing entropy states that "a system will always move towards the most disordered state, never in the other direction".
Now, I understand why it would be virtually impossible for a system to decrease it's entropy, just as it is virtually impossible for me to solve a Rubik's cube by making random twists. However the (ever so small) probability remains.
Why does this law underpin so much of modern physics? Why is a theory that breaks this law useless, and why was Maxwell's demon such a problem? Does this law not just describe what is most likely to happen in complex systems, not what has to happen in all systems?
thermodynamics statistical-mechanics entropy arrow-of-time
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edited Oct 28 '12 at 23:22
Qmechanic♦
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Hannesh
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Hannesh, you are correct that the second law of thermodynamics only describes what is most likely to happen in macroscopic systems, rather than what has to happen. It is true that a system may spontaneously decrease its entropy over some time period, with a small but non-zero probability. However, the probability of this happening over and over again tends to zero over long times, so is completely impossible in the limit of very long times.
This is quite different from Maxwell's demon. Maxwell's demon was a significant problem because it seemed that an intelligent being (or more generally any computer) capable of making very precise measurements could continuously decrease the entropy of, say, a box containing gas molecules. For anyone who doesn't know the problem, this entropy decrease could be produced via a partitioning wall with a small window that the demon can open or close with negligible work input. The demon allows only fast-moving molecules to pass one way, and slow-moving ones the other way. This effectively causes heat to flow from a cold body of gas on one side of the partition to a hot body of gas on the other side. Since this demon could be a macroscopic system, you then have a closed thermodynamical system that can deterministically decrease its entropy to as little as possible, and maintain it there for as long as it likes. This is a clear violation of the second law, because the system does not ever tend to thermodynamic equilibrium.
The resolution, as you may know, is that the demon has to temporarily store information about the gas particles' positions and velocities in order to perform its fiendish work. If the demon is not infinite, then it must eventually delete this information to make room for more, so it can continue decreasing the entropy of the gas. Deleting this information increases the entropy of the system by just enough to counteract the cooling action of the demon, by Landauer's principle. This was first shown by Charles Bennett, I believe. The point is that even though living beings may appear to temporarily decrease the entropy of the universe, the second law always catches up with you in the end.
thermodynamics - Why does the law of increasing entropy, a law arising from statistics of many particles, underpin modern physics? - Physics Stack Exchange