Thermodynamics

By being "pushed from behind", by the constant influx of energy from the Sun.The second law of thermodynamics states that entropy of a system increases but to calculate the entropy change you must include any entropy that flows across the boundary of the system. Living beings cause a reduction of entropy on the Earth, the heat radiated from the Earth to space causes a greater increase of entropy on Earth, for an overall increase; the secobnd law is satisfied. The energy from the Sun keeps us warm enough to have useful energy available and to continue to radiate enough energy to space to offset the entropy decrease of living things. It can't go on forever; in 5-6 billion years we're toast.

That doesn't have anything to do with thermodynamics, but it's a worthwhile question. (Many creationists think that the second law has to do with mechanisms ... it does not. Entropy is a property, which is a technical thermodynamic term meaning that its value depends only on the current state of the system and not at all on how the system got to that state; so the second law of thermodyanmics is not concerned with how things happen.)The sun's energy sustains all life by providing energy that drives chemical reactions in a direction that they would not take if the energy were not available, or to push chemical reactions "over the hump" of activation energy required to get them going. Once you have life that replicates itself but replicates imperfectly, evolution just happens.There's lots of discussion of entropy as it relates to evolution at Thermodynamics, Evolution and Creationism.--------------On another note, it's dangerous to equate entropy with disorder. Formally, the pizza box example given earlier in this thread is not really an example of entropy. Some kinds of disorder are entropy and some kinds are not. As is said at The second law of thermodynamics and evolution (an excellent site without complex math, well worth reading in its entirety):

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As part of their attempts to challenge evolution, some religious writers have included comments to the effect that the second law — what they have called "the law of disorder" — strictly prohibits the chance formation of complicated stuctures from simple parts, including complex molecules from simple ones. This site, and especially http://www.secondlaw.com, have shown repeatedly that it is fallacious to view the second law as a predictor of disorder. The second law concerns energy, not patterns of objects.{emphasis added - JonF}

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Or, from Note on Entropy, Disorder and Disorganization (which is pretty technical):

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The error or ambiguity which is involved in the identification of entropy with disorder is well illustrated by an example I have used previously: the spontaneous crystallisation of a super-cooled melt. Under adiabatic {meaning "no heat transfer" - JonF} conditions the entropy of this system increases, but it would involve special pleading to substantiate a claim to the effect that its disorder also increases!

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Finally, from Shuffled Cards, Messy Desks, and Disorderly Dorm Rooms Examples of Entropy Increase? Nonsense!

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There is no more widespread error in chemistry and physics texts than the identification of a thermodynamic entropy increase with a change in the pattern of a group of macro objects. The classic example is that of playing cards. Shuffling a new deck is widely said to result in an increase in entropy in the cards. ... Thermodynamic entropy changes are dependent on changes in the dispersal of energy in the microstates of atoms and molecules. A playing card or a billiard ball or a blue sock is a package, a sealed closed system, of energetic microstates whose numbers and types are not changed when the package is transported to a new site from a starting place. All macro objects are like this. Their relocation to different sites does not create any permanent additional energetic microstates within them. (Any temporary heating effects due to the initiation and cessation of the movement are lost to the environment.) Thus, there is a zero change in their physical entropy as a result of being moved.

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{edited to change "energy were available" to "energy were not available"}This message has been edited by JonF, 02-13-2005 11:04 AM

No, no, a thousand times no!!! All systems operate in accordance with the second law. Open systems are just a bit more complex.

Yup. IIRC Evolution has been shown to increase Kolmogorov complexity, although I don't have the reference to hand. One difficulty with Kolmogorov complexity is that you can calculate bounds on it but you can't calculate it.

It's totally different, and not related. Kolmogorov complexity has to do with compression and the Universal Turing Machine (UTM) that's doing the compressing. Shannon entropy has to do with the probability of a particular string appearing from a particular space of strings. About all it adds the the EvC debate is another buzzword for creationists to misunderstand and misapply. There's an interesting thread at For Sean Pitman- more on Kolmogorov Complexity in which R. Baldwin demponstrates that relative to a particular carefully-selected UTM the Kolmogorov complexity of the Encyclopedia Britannica is two bits!!!! Of course, that carefully-selected UTM is a little on the complex side ...Kolmogorov Complexity has uses in the theory of computing, but not in any investigation about the source of the complexity of life.

I once posted something very similar on t.o and was gently corrected; the heat radiated from the Earth is also significant. Evidence.

Oh, and I forgot this excellent and straightforward exposition of entropy and disorder: Entropy, Disorder and Life.

The peanut gallery demands a suspension!!

Yup. Exactly. Nope, not at all like the wind or an earthquake. Like a mechanism or mechanisms for generating variation (mutation, random gene drift, ...) and a powerful filter for selecting the "best" randomly generated organisms (that is ... ta-daa ... natural selection). We know that these natural forces can generate complex (however you define complex) and ordered (however you define ordered) systems, because we've seen it happen and we use those processes as tools.There's a good article on using these mechanisms as tools in Technology Review last month: . Here's a picture from that article, showing an antenna designed for a very difficult task ... no human designer would ever think up a design like this: And, of course, there's the classic example of evolving an electronic circuit to discriminate between waves at different frequencies; the result used less resources than any human designer thought possible, and worked in a way that no human designer had ever thought of, and took advantage of a property of the environment that the humans weren't even aware of. See An Evolved Circuit, Intrinsic in Silicon, Entwined with Physics. Given a few million years of evolution, we get whatever the descendants of the monkeys decide to build. Maybe a house.(By the way, our closest primate relatives are chimpanzees and apes, not monkeys).{fixed typo}This message has been edited by JonF, 02-14-2005 12:57 AM

OK.You are coming pretty close to pressing some standard buttons; the "I didn't evolve from no monkey" button, the "If we evolved from monkeys why are there stil monkeys?" button, and the "Evolution is like expecting a tornado in a junkyard to produce a 747" button. Many of us have seen these buttons pressed many times and we're thoroughly sick of them ... and possible oversensitive to someone who may well be innocently raising their spectres in our minds without realizing it.

When I took graduate thermo, it was taught by two professors, each doing every other lecture. One was a hands-on guy -- steam, turbines, engines of all types, refrigeration, what's the enthalpy, and so on. The other was a Greek (many theoretical thermodynamicists have been Greek), whose name I forget; he wrote the Britannica article some years ago. He was Dr. Theory. Non-equilibrium systems, definitions stripped to their absolute minimum need for axioms and maximum generality. He once spent an entire lecture deriving the concept of temperature from first principles (and was not pleased when I pointed out that he had assumed that a function for which all x0 yields f(x)>0 necessarily has f(0)=0 ... he hadn't established the requisite continuity or differentiability or some such, and it would have lengthened the derivation considerably).You can probably imagine that bouncing back and forth between these guys was a little disconcerting. Each didn't think much of the other and tried to hide it. I did really well; I have no idea how.Anyhow, with that background, the theory guy's first law was "Any interaction between two systems, in which either of the systems could have been replaced by a weight falling in a gravitational field, is work". Alas, I have forgotten his definition of the second law. I do remember that it was a doozy.

Nope. We're saying that nobody has been able to come up with any violations of the second law involved in the natural origin of the first self-replicating forms, in any of the many hypotheses that have been proposed. Nobody would propose a hypothesis that violated the second law.

He and I and, I bet, everyone in this thread knows that. Either you are misremembering/misinterpreting, or your teacher was not quite correct. I bet on the former (having observed how you have misinterpreted so many things -- that's just an observation, not intended as an insult).It is incorrect (although, sadly, it is still sometimes done) for an "evolutionist" to claim that the second law applies only to closed systems, and the Earth is not a closed system, and therefore the second law doesn't apply. That's flat-out wrong, and that's probably what your teacher referred to.But Percy didn't write that. He wrote a correct definition involving a closed system. This definition, combined with other definitions and results, can be generalized to apply to open systems such as the Earth. Exactly how this is done requires some moderately advanced math and quite a bit of time spent learning stuff. We're not going to be able to get deeply into that in this thread.The things to take home from Percy's messae are:

• Order and disorder of macroscopic systems is not entropy.
• Entropy is not something that organisms accumulate during their lives.
• Anything that contains a bunch of atoms obeys the second law, at all times.
• Nothing accepted as mainstream science, not evolution or abiogenesis or anything, is known to have violated the second law ... and people have looked for such violations.
• Creationists are lousy sources of information about thermodynamics, and non-technical sources may be lousy sources of information about thermodynamics.

Nobody knows those odds. Nobody. We just don't have the information required to calculate or even estimate the odds.Research has shown that people are downright terrible at estimating the odds of everyday occurrences. There's no way that anyone can come up with any kind of valid estimate of the probability of somethng so far out of our everyday experience as abiogenesis.So, don't say you don't like the odds. Say you don't like the idea, if you want; but you have no claim to know any odds to like or not like. Nobody has such a claim.We do know that many critical steps are possible. We do not know of any critical step that is impossible. We know that life is here. We have no evidence of anything supernatural being required, outside of the holy writings of a few religions.

You misunderstand. We have written many explanations and given many references -- there is no law that states that everything in the universe moves from order to disorder. That's not what the second law says or is about. If that is indeed what it says, then it is oversimplifying so far that we might as well just say that it's wrong. If that is indeed what they taught (and I hope that they did not), then they were oversimplifying so far that we might as well just say that they were wrong.