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Where is the difference here?

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Since my Cornell conference contribution has generated dozens of critical comments on another thread, I feel compelled to respond. I hope this is the last time I ever have to talk about this topic, I’m really tired of it.

Here are two scenarios:

1. A tornado hits a town, turning houses and cars into rubble. Then, another tornado hits, and turns the rubble back into houses and cars.

2. The atoms on a barren planet spontaneously rearrange themselves, with the help of solar energy and under the direction of four unintelligent forces of physics alone, into humans, cars, high-speed computers, libraries full of science texts and encyclopedias, TV sets, airplanes and spaceships. Then, the sun explodes into a supernova, and, with the help of solar energy, all of these things turn back into dust.

It is almost universally agreed in the scientific community that the second stage (but not the first) of scenario 1 would violate the second law of thermodynamics, at least the more general statements of this law (eg, “In an isolated system, the direction of spontaneous change is from order to disorder” see footnote 4 in my paper). It is also almost universally agreed that the first stage of scenario 2 does not violate the second law. (Of course, everyone agrees that there is no conflict in the second stage.) Why, what is the difference here?

Every general physics book which discusses evolution and the second law argues that the first stage of scenario 2 does not violate the second law because the Earth is an open system, and entropy can decrease in an open system as long as the decrease is compensated by increases outside the Earth. I gave several examples of this argument in section 1, if you can find a single general physics text anywhere which makes a different argument in claiming that evolution does not violate the second law, let me know which one.

Well, this same compensation argument can equally well be used to argue that the second tornado in scenario 1 does not violate the second law: the Earth is an open system, tornados receive their energy from the sun, any decrease in entropy due to a tornado that turns rubble into houses and cars is easily compensated by increases outside the Earth. It is difficult to define or measure entropy in scenario 2, but it is equally difficult in scenario 1.

I’ll save you the trouble: there is only one reason why nearly everyone agrees that the second law is violated in scenario 1 and not scenario 2: because there is a widely believed theory as to how the evolution of life and of human intelligence happened, while there is no widely believed theory as to how a tornado could turn rubble into houses and cars. There is no other argument which can be made as to why the second law is not violated in scenario 2, that could not equally well be applied to argue that it is not violated in scenario 1 either.

Well, in this paper, and every other piece I have written on this topic, including my new Bio-Complexity paper , and the video below, I have acknowledged that, if you really can explain scenario 2, then it does not violate the basic principle behind the second law. In my conclusions in the Cornell contribution, I wrote:

Of course, one can still argue that the spectacular increase in order seen on Earth is consistent with the underlying principle behind the second law, because what has happened here is not really extremely improbable. One can still argue that once upon a time…a collection of atoms formed by pure chance that was able to duplicate itself, and these complex collections of atoms were able to pass their complex structures on to their descendents generation after generation, even correcting errors. One can still argue that, after a long time, the accumulation of genetic accidents resulted in greater and greater information content in the DNA of these more and more complex collections of atoms, and eventually something called “intelligence” allowed some of these collections of atoms to design cars and trucks and spaceships and nuclear power plants. One can still argue that it only seems extremely improbable, but really isn’t, that under the right conditions, the influx of stellar energy into a planet could cause atoms to rearrange themselves into computers and laser printers and the Internet.

Of course, if you can come up with a nice theory on how tornados could turn rubble into houses and cars, you can argue that the second law is not violated in scenario 1 either.

Elizabeth and KeithS, you are welcome to go back into your complaints about what an idiot Sewell is to think that dust spontaneously turning into computers and the Internet might violate “the basic principle behind the second law,” and how this bad paper shows that all of the Cornell contributions were bad, but please first give me another reason, other than the one I acknowledged, why there is a conflict with the second law (or at least the fundamental principle behind the second law) in scenario 1 and not in scenario 2? (Or perhaps you suddenly now don’t see any conflict with the second law in scenario 1 either, that is an acceptable answer, but now you are in conflict with the scientific consensus!)

And if you can’t think of another reason, what in my paper do you disagree with, it seems we are in complete agreement!!

[youtube 259r-iDckjQ]

Comments
cantor, If you disagree with me, you are welcome to show exactly where and why you think I am mistaken. Just quote the points you disagree with and describe what you think my errors are. Then tell us what you think is correct and why.keiths
July 3, 2013
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KeithS,
By accepting Granville’s paper, the organizers showed that the BI was not a serious scientific conference. Springer did the right thing in refusing to publish
Obviously I don't agree, but even if your opinion of my paper is correct, out of 24 papers there are always going to be a weak one or two, that does not mean the others were bad. Two of the best were by Jon Wells: 1. Not junk after all: non-protein-coding DNA carries extensive biological information 2. The membrane code: a carrier of essential information that is not specified by DNA and is inherited apart from it. Wells' points in both of these talks are being proved spectaculary correct by evidence accumulated recently. Why don't we talk about these a little? In any case, Nick and the others who demanded Springer withdraw the book, didn't even know I was a participant, or what any of the talks were about, for that matter.Granville Sewell
July 3, 2013
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Andre, I have no idea what you are trying to say. Could you rephrase that?keiths
July 3, 2013
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keiths Your 10 reasons are bunked, here is one... A net loss of mass which is related to energy means an increase in entropy.Andre
July 3, 2013
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Eric,
Stop being silly. No-one is arguing that the 2nd law has been violated. Granville has not made that argument either.
Well, Granville is right here. Let's ask him. Meanwhile, look at what he wrote in the OP:
Elizabeth and KeithS, ...please first give me another reason, other than the one I acknowledged, why there is a conflict with the second law (or at least the fundamental principle behind the second law) in scenario 1 [a tornado turning rubble into pristine houses and cars] and not in scenario 2 [evolution and its downstream consequences]? (Or perhaps you suddenly now don’t see any conflict with the second law in scenario 1 either, that is an acceptable answer, but now you are in conflict with the scientific consensus!)
keiths
July 3, 2013
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KeithS wrote: The contents of Granville’s paper are awful. Based on those contents, and using Granville’s own words, I have shown that Granville... You have shown no such thing. You are taking down a strawman of your own making. It seems 2LoT is the new "evolution". It has many different meanings, and is too easily equivocated as Liddle & KeithS do. If you have some constructive criticism of what Sewell actually wrote in his paper, we'd all like to hear it. Otherwise, please take your strawman arguments over to Panda's Thumb or Why Evolution is true or Pharyngula where they'll fit right in.cantor
July 3, 2013
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On the other thread, Eric Anderson comments:
The compensation idea is, frankly, silly. The reason a tree can exist has nothing to do with the fact that the Earth is an open system and the tree’s reduced entropy is “compensated” by increased entropy at the sun. Otherwise, tell me, please, what physical mechanism alerts the Sun to the fact that there is a tree growing on the Earth and, therefore, the Sun should increase its entropy?
Eric, You have misunderstood the compensation argument. The argument is valid, but your understanding of it isn't. In the case of Earth, the compensation is not taking place on the Sun. In fact, the radiation emitted by the Sun actually works toward reducing its own entropy. Instead, the compensation happens because Earth is radiating energy out into its surroundings. How do the surroundings "know" that they should increase their entropy? Because they receive the radiation from the Earth. I'll cross-post some of my remarks about the compensation argument below.keiths
July 3, 2013
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Mark Frank and keiths: Stop being silly. No-one is arguing that the 2nd law has been violated. Granville has not made that argument either. As I understand it, what he is saying is that if what evolutionists claim occurred (natural abiogenesis, significant increases in organismal structure and complexity, etc.) in fact occurred, that it would contradict our uniform and repeated experience and would contradict the underlying principle of the 2nd law. Nothing to do with heat; nothing to do with open vs. closed; nothing to do with alleged compensation of entropy elsewhere. Granville is not arguing that evolution shows the 2nd law has been violated. Rather, that the 2nd law shows that evolution (at least the key alleged macro events) is unlikely to the point of being a non-starter.Eric Anderson
July 3, 2013
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Elizabeth:
On earth, we are wide open to the sun, and so it’s probably easier to think of the earth-sun as a one system.
I was saving this point for later, but Elizabeth beat me to it! :) This is one of the reasons why the "explanations" for how evolution could occur that rely on "because the Earth is an open system" are absolutely absurd. The openness or closedness of the Earth system is utterly irrelevant to the question of whether molecules can spontaneously come together to form life, or whether simple organisms can evolve into more complex organisms. To repeat: It is a complete red herring. As is the whole "compensation" idea.Eric Anderson
July 3, 2013
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Elizabeth:
However, a tornado does not necessarily result in a more uniformly diffused distribution of contents. It could well result in a greater concentration of them (messy though that concentration would be). And if we define “low entropy” as a configuration more able to do work, then if some of the stuff is up a tree, then it can do work than it could when it was neatly arranged on the floor of the house.
Well, all you have said, really, is that a tornado can convert some of its kinetic energy into potential energy. Big deal. So some of the tornado's original energy is now available as potential energy (your stuff up in a tree). In other words, some of the tornado's energy has not fully dissipated yet, but is still available for a temporary time in another form. But you haven't demonstrated at all how this could possibly apply to help explain the formation of, say, living systems. It sounds to me like you and Granville are talking past each other because (i) you are saying that the 2nd law only applies to head distribution and nothing else, and (ii) Granville is saying that it applies more broadly and that this broader application is well-known.Eric Anderson
July 3, 2013
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Prof. Sewell, the good news: indeed the funny reactions of evolutionists are proof that they fear the 2nd law as fire. They apply all their best tactics to hidden the thing: the 2nd law disproves evolution. Please, continue tirelessly your battle, thank you.niwrad
July 3, 2013
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Granville I am jumping in here without having followed the debate because it is the opportunity to ask a very basic question. Are you proposing that the 2nd law of thermodynamics is not always true because an intelligent mind can overcome it? Surely, if you can prove this, it puts you in line for a Nobel prize.Mark Frank
July 3, 2013
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A comment from last night, cross-posted from the other thread:
Timaeus, Scientific papers are judged by their contents. The contents of Granville’s paper are awful. Based on those contents, and using Granville’s own words, I have shown that Granville: 1. Mistakenly asserts that “the increase in order which has occurred on Earth seems to violate the underlying principle behind the second law of thermodynamics, in a spectacular way.” 2. Titles his paper Entropy, Evolution and Open Systems without realizing that the second law is actually irrelevant to his improbability argument, since it is not violated by evolution. 3. Misunderstands the compensation argument and incorrectly rejects it. 4. Fails to understand that the compensation argument is a direct consequence of the second law, and that by rejecting it he is rejecting the second law itself! 5. Fails to realize that if the compensation argument were invalid, as he claims, then plants would violate the second law whenever their entropy decreased. 6. Asserts, with no evidence, that physics alone cannot explain the appearance of complex artifacts on Earth. 7. Offers, as evidence for the above, a thought experiment involving a simulation he can neither run nor analyze. 8. Declares, despite being unable to run or analyze the simulation, that he is “certain” of the outcome, and that it supports his thesis. 9. Confuses negentropy with complexity, as Lizzie explained. 10. Conflates entropy with disorder, as Lizzie explained. Granville was unable to defend his paper, so he bailed out of the thread. You are now retreating also — probably a wise move. It remains to be seen what Eric and CS3 will do. If Lizzie and I are able to expose egregious faults in Granville’s paper, using his own words, and none of you are capable of defending it, then how can you claim that his paper was good science that deserved to be accepted by the BI organizers? By accepting Granville’s paper, the organizers showed that the BI was not a serious scientific conference. Springer did the right thing in refusing to publish.
keiths
July 3, 2013
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Granville,
Since my Cornell conference contribution has generated dozens of critical comments on another thread, I feel compelled to respond.
It's odd that you would post a link to your own paper but not to the thread containing the critical comments.keiths
July 3, 2013
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Elizabeth, Please note my footnote 1 in the Bio-Complexity paper:
There are many thermodynamic entropies, corresponding to different degrees of experimental discrimination and different choices of parameters. For example, there will be an increase of entropy by mixing samples of O-16 and O-18 only if isotopes are experimentally distinguished. (R. Carnap, Two Essays on Entropy, Univ. of California Press 1977.)
Do you claim that the entropy which increases when two oxygen isotopes mix, mentioned by Carnap, is really just thermal entropy, which you seem to think is the only legitimate entropy? Or is he just confused too? What about the "chromium entropy" in an isolated solid, which increases when chromium becomes more uniformly distributed (scenario B in the Bio-Complexity paper)? That is guided by exactly the same equations as thermal entropy, the only difference is chromium is diffusing instead of heat. Do you claim that chromium diffusion has nothing to do with the second law? Or that chromium diffusion is really all about thermal entropy also? And of course I don't agree that tornados decrease entropy, they increase it. Tornados running backward decrease entropy, and the "entropy" I am talking about has little or nothing to do with thermal entropy. The second law, in its more general forms, is about applying probability at the microscopic level to predict macroscopic change, not just about thermal entropy. The application to thermal entropy is only one of many applications. Obviously, you are using only statement (1) of the second law, given in my Bio-Complexity paper, I am using the more general statements (2) and (3). If you believe that tornados turning a town into rubble "decrease" entropy, we are obviously going to disagree about the application of the second law to evolution! Won't you at least admit that there are a lot of good physicists (the majority, I'm sure) who would say that tornados increase entropy, in the more general sense, so I am in good company, I am not just reading out of date texts.Granville Sewell
July 3, 2013
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Dr Liddle Think about this.... entropy is increasing, if entropy is constantly increasing due to mass loss how is humans, cars and computers possible? The energy we receive from the sun does not negate the loss of matter. There is no equilibrium as you would like to believe.Andre
July 3, 2013
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Granville, First of all, thank you for posting this and allowing comments. I think this is an interesting topic that merits discussion, but many of your posts in the past have been closed to comments. Second, I realize you are tired of talking about it, but I hope you will be patient with us and will have some time to stick with this thread for a bit as the discussion unfolds. Thank you,Eric Anderson
July 3, 2013
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Prof. Sewell, You debate evolutionists trying to explain the obvious: anything material tend spontaneously towards disorganization. In fact, this is an interpretation of the 2nd law: systems spontaneously go towards the more probable states. The more probable states are those more numerous, then those disorganized. In very simple terms this is the question. Evolutionists disagree because they believe that biological systems spontaneously organize themselves. That is, exactly the inverse of what the 2nd law states.niwrad
July 3, 2013
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Andre:
I must admit, I have great difficulty understanding what Dr Liddle is trying to say.
Well, the 2nd Law of Thermodynamics isn't as easy as it looks! But essentially, what it says is that within a closed system the amount of work that can be done is fixed, and as a result, after that work is done, there is less that can still be done. We can think of work as "heat", so that if we raise the temperature of one part of the system, we inevitably cool it by a slightly greater amount in some other part, and so the average temperature of the system is always dropping. So a system that starts hot can do more work before it reaches maximum entropy than a system that starts cold, but neither can do anything to increase the total amount of work that can be done. Or we could think of work as, say, altering things. A system in which all the objects are on a high shelf can alter things by falling off and making a dent in the floor. But once all the objects are on the floor, no more work can be done. However, in an open system, the amount of work that can be done by the system can increase - we could heat the system up again, or put all the objects back on a high shelf. But to "fund" that work, we'd need to get it from some other system, and as a result, that other system would have a reduced amount of work it could still do. On earth, we are wide open to the sun, and so it's probably easier to think of the earth-sun as a one system. We can certainly make things hotter on earth, by putting them in the sun. But that hasn't violated the 2nd Law because the reason the sun can do this is that it is doing work, and, as a result, cooling down. The sense in which entropy is increased when work is done is simply that the system adopts a more uniform configuration. It might look more "ordered", or it might look less "ordered". But what it will be, is in some sense, more uniform. Ultimately, the system will approach cold uniformity - no hot spots, no lumps. Designing things sometimes makes the parts of the system hotter, or lumpier, but often not, and even when it does, it is at the cost of cooling and increase in uniformity elsewhere. Tornadoes can also make things hotter or lumpier, also endothermic chemical reactions - the capacity to make something hotter or lumpier is not unique to designers or designed things, and again, the 2nd Law is not violated when it happens.
The earth is losing more than what it is receiving. I think currently the earth is losing about 50 000 tonnes of mass per year and only gaining 40 000 tonnes. If we are losing more that we get can anyone explain to me how its possible for that atoms could become humans, cars and computers
I don't see how that would stop us. We aren't running short of material yet!
The question is… are we really and open system as consensus would like us to believe? If we have net loss how on earth is humans even possible?
We are "open" in the sense that we are warmed by the sun. The solar system itself is fairly closed, although it does receive energy from other stars, and material from outside the system.Elizabeth B Liddle
July 3, 2013
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Elizabeth, The first formulations of the second law were only about heat and energy, the later ones are more general. The second law applies to the diffusion of anything that diffuses, not just heat, that is acknowledged by everyone, the same equations apply, the same definition of entropy applies (except you replace temperature by concentration of the diffusing element). So to claim that the second law is only about energy is absolutely false, it applies in quantitative form to many other things that have nothing to do with heat or energy, see footnote 1 in my BIO-Complexity paper.
In your paper, you equate "entropy" with "randomness", and argue that randomness can apply to macroscopic objects as well as atoms and molecules. Unfortunately you do not define "randomness". However, you do imply that by "more random" you mean "more uniformly diffused", which is fine. In that sense, higher entropy means more uniformity. However, a tornado does not necessarily result in a more uniformly diffused distribution of contents. It could well result in a greater concentration of them (messy though that concentration would be). And if we define "low entropy" as a configuration more able to do work, then if some of the stuff is up a tree, then it can do work than it could when it was neatly arranged on the floor of the house. Similarly, when we build a computer, we do not necessarily end up with a more, or less, uniform distribution of contents than we started with. We may have gathered together the requisite parts from many regions, but we have used fuel to do so. So again, no 2nd law violation has occurred.
And most people, but not everyone, further generalize it to things like books burning, tornados destroying houses, etc., to claim that such generalizations are not valid depends on which of several statements of the second law you use.
Well, a burnt book clearly has more thermodynamic entropy than an unburnt book. But a book does not necessarily have more less thermodynamic entropy than the pieces of paper and ink that it consisted of before.
And I’m really tired of being talked down to, as though I know nothing of the topic and you need to bring me up to speed. I wish someone would actually read my papers before commenting on them.
I have read your MI paper, your BIOcomplexity paper, and your New Perspectives paper, each several times, in great detail. I apologise if I seem to "talk down" to you as though you "know nothing of the topic", but as far I can tell you have made a major error of understanding. It is not "talking down" to someone to point out that they have made an error. Yes, you can apply the 2nd Law to macroscopically diffusing things like an unmaintained house, in which, over time, bits of it end up on the floor, including the roof and the contents, where they have less potential energy, and thus less capacity to do work. But you can't then claim that tidying up that house violates the 2nd law, because tidying up that second law can only be done by something that is fueled (e.g. me), and that fuel will increase in entropy as I burn it up during my tidying. A system that has low entropy is in a configuration that cannot easily do work. A house is not "low entropy" when it is tidy and "high entropy" when it is messy. If my son puts a booby-trap on his bedroom door, so that all his soft toys (or worse) fall on my head when I come in, he might have messed up his room to do it, but the room has lower entropy when his toys are on top of the door than when they were on the shelves. You are clearly a fine mathematician, Granville, but you seem to have learned your physics from out-of-date and elementary text books. That's why your paper is wrong. The 2nd Law of thermodynamics is not violated when someone makes a computer or tidies up a house, because building a computer or house does not usually result in significantly lower entropy systems than their ingredients (and may be higher), plus, even if when they do (and building a fridge does create a lower entropy system) the 2nd Law would still not have been violated, because these things require fuel to run and build, and using fuel increases entropy. And indeed a tornado itself is an excellent example of local decrease in entropy. Do you think that tornadoes violate the 2nd Law of thermodynamics? Thermodynamic entropy is not the same thing as chaos. Quite the opposite. Chaotic systems (like tornadoes) represent a decrease in local entropy, not an increase.Elizabeth B Liddle
July 3, 2013
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I must admit, I have great difficulty understanding what Dr Liddle is trying to say. The earth is losing more than what it is receiving. I think currently the earth is losing about 50 000 tonnes of mass per year and only gaining 40 000 tonnes. If we are losing more that we get can anyone explain to me how its possible for that atoms could become humans, cars and computers The question is... are we really and open system as consensus would like us to believe? If we have net loss how on earth is humans even possible?Andre
July 3, 2013
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Elizabeth, The first formulations of the second law were only about heat and energy, the later ones are more general. The second law applies to the diffusion of anything that diffuses, not just heat, that is acknowledged by everyone, the same equations apply, the same definition of entropy applies (except you replace temperature by concentration of the diffusing element). So to claim that the second law is only about energy is absolutely false, it applies in quantitative form to many other things that have nothing to do with heat or energy, see footnote 1 in my BIO-Complexity paper. And most people, but not everyone, further generalize it to things like books burning, tornados destroying houses, etc., to claim that such generalizations are not valid depends on which of several statements of the second law you use. Granville Sewell
July 3, 2013
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Granville: Thanks for your response.
Well, perhaps “almost universally agreed” is a bit of an exaggeration, in the Bio-Complexity paper I acknowledge that “Although most general physics textbooks give examples of entropy increases that are difficult to quantify, such as wine glasses breaking or books burning, because it is more difficult to define an associated entropy precisely in scenario C, some scientists are reluctant to apply the second law to things like tornados.”
It's an exaggeration to the point of falsity, Granville. A computer simply does not have less entropy than the bits of the computer had before assembly (or after disassembly). Some artefacts do (a fridge, cement, a bridge, dynamite), but many don't, and those that do don't violate the second law, because the local entropy decrease is gained at the cost of entropy increase in the fuel used to run or build the artefact. Of course it is true that a tornado is vastly less likely to build a nice duplex than a good builder is, but that isn't because the builder violates the second law of thermodynamics. The 2nd Law of thermodynamics says nothing about "order" in the sense in which you are using the term.
Certainly the first formulations of the second law, which were all about heat and energy, are not threatened by evolution. But nearly all general physics texts (thermodynamics texts, not so much, since they prefer quantifiable applications) do give examples of “entropy” increases (in the more general sense) which have nothing to do with heat or energy, such as tornados, rust, fire, glasses breaking, cars colliding, etc. Isaac Asimov, in the Smithsonian magazine, even talked about the entropy increase associated with a house becoming more messy (see my footnote 6 in my Cornell contribution).
It's perfectly true that any artefact, left to itself, unmaintained, will tend to increase in entropy - timbers will decay and fall, things will be taken down from high shelves and not put back, dust will grow thick on the floor, etc. All these effects do indeed represent an increase in entropy - a rearrangement of matter less able than formerly to do work. What is not true is that the same will result from a tornado, which may well lift books into trees and roofs up mountains, where they can do more work, not less. And Asimov also rightly says that a human brain has less entropy than the molecules of which it is composed - so has a tree. You can prove this by using either as fuel for a barbecue. But again, no violation of the 2nd Law has occurred, because brains grow by virtue of the food we eat (or our mothers eat) and trees grow by virtue of increasing entropy in the sun. However, Asimov is in danger of making the same mistake as you are making, as is your other citee, Peter Urone. They do not actually make the same mistake, as it is true that human endeavours do sometimes result in local decreases of entropy, courtesy of increases in entropy used to achieve it, but they seem perilously closer to equating: "looks highly ordered and not chaotic" with "has low entropy".
So if I am confused in applying the more general formulations of the second law to things like tornados, I am at least in good company, as nearly all general physics textbooks do this, so I think it is quite unfair to say, as KeithS does, that I would be laughed out of any physics meeting.
In your defense, it is true that basic physics text books are often very carelessly written in an attempt to create an accessible mental picture for the students, and the popular metaphor of "entropy" as "disorder" is highly misleading. There has been considerable concern about this in the pedagogical literature, for instance: Disorder - A Cracked Crutch for Supporting Entropy Discussions
To aid students in visualizing an increase in entropy, many elementary chemistry texts use artists' before-and-after drawings of groups of "orderly" molecules that become "disorderly". This seems to be a useful visual support, but it can be so misleading as actually to be a failure-prone crutch. Ten examples illustrate the problem.Entropy is not disorder, not a measure of chaos, not a driving force. Energy's diffusion or dispersal to more microstates is the driving force in chemistry. Entropy is the measure or index of that dispersal. In thermodynamics, the entropy of a substance increases when it is warmed because more thermal energy has been dispersed within it from the warmer surroundings. In contrast, when ideal gases or liquids are allowed to expand or to mix in a larger volume, the entropy increase is due to a greater dispersion of their original unchanged thermal energy. From a molecular viewpoint all such entropy increases involve the dispersal of energy over a greater number, or a more readily accessible set, of microstates. Frequently misleading, order-disorder as a description of entropy change is also an anachronism. It should be replaced by describing entropy change as energy dispersal--from a molecular viewpoint, by changes in molecular motions and occupancy of microstates.
Undergraduate students’ understandings of entropy and Gibbs free energy
Only a small minority of students showed a ‘sound understanding’ of the concept of entropy and Gibbs free energy. This weak understanding was mirrored in Pinto’s14study of Catalan undergraduate physics students, who did not connect different aspects of the Second Law with one another and few students used entropy to explain everyday processes. Sozbilir13found that students attempted to explain entropy as ‘disorder’. However, ‘almost all of the respondents defined entropy from the visual disorder point of view, indicating chaos, randomness or instability in some cases’. He found that the term ‘disorder’ was used to refer to movement, collision of particles and the extent to which things were ‘mixed up’. Students did not have clear understanding of enthalpy and energy of a system and seemed to confuse the kinetic energy of a system and entropy. Some also confused enthalpy with Gibbs free energy. Similar findings were found by Ribiero et al15and Selepe and Bradley.17 No student used microstates to explain disorder (Sozbilir13).
Elizabeth B Liddle
July 3, 2013
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Elizabeth, Well, perhaps "almost universally agreed" is a bit of an exaggeration, in the Bio-Complexity paper I acknowledge that "Although most general physics textbooks give examples of entropy increases that are difficult to quantify, such as wine glasses breaking or books burning, because it is more difficult to define an associated entropy precisely in scenario C, some scientists are reluctant to apply the second law to things like tornados." Certainly the first formulations of the second law, which were all about heat and energy, are not threatened by evolution. But nearly all general physics texts (thermodynamics texts, not so much, since they prefer quantifiable applications) do give examples of "entropy" increases (in the more general sense) which have nothing to do with heat or energy, such as tornados, rust, fire, glasses breaking, cars colliding, etc. Isaac Asimov, in the Smithsonian magazine, even talked about the entropy increase associated with a house becoming more messy (see my footnote 6 in my Cornell contribution). So if I am confused in applying the more general formulations of the second law to things like tornados, I am at least in good company, as nearly all general physics textbooks do this, so I think it is quite unfair to say, as KeithS does, that I would be laughed out of any physics meeting.Granville Sewell
July 3, 2013
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Collin:
“It is evident that entropy is not leaving the earth fast enough to compensate for the order developing on the earth.”
But it isn't evident. Granville has confused two meanings of the word "order" and claims that an "ordered" thing, like a pre-tornado house has less entropy than a "disordered" thing like a post tornado house. It doesn't. The post -tornado house could conceivably have less entropy, if the tornado had deposited lots of its stuff up a tree. Sure it would be more "disordered" in the common or garden sense. But that isn't the sense in which low entropy is order. If a thing has low entropy, that just means its bits are arranged in a way that they can do work. If the sofa ended up at the top of a tree, it could do work by making a hole in the ground when it fell back down. Before the tornado, it couldn't.Elizabeth B Liddle
July 3, 2013
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Granville, May I suggest an addition to your theory (forgive me if you've already said this before): "It is evident that entropy is not leaving the earth fast enough to compensate for the order developing on the earth." This assertion would require some kind of measurement of entropy and order and applying it over the billions of years of earth's existence. That would be difficult, but I wonder if a good estimate is possible.Collin
July 3, 2013
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Granville:
It is almost universally agreed in the scientific community that the second stage (but not the first) of scenario 1 would violate the second law of thermodynamics
No, it is not "almost universally agreed in the scientific community that the second stage (but not the first) of scenario 1 would violate the second law of thermodynamics." You have confused "order" as in low entropy with "order" as in "not chaos". You seem to think that a tidy house, or a computer, has less entropy than a messy house, or a computer after it has been sat on by an elephant. It doesn't. And if you don't think that, then why think that the appearance of "humans, cars, high-speed computers, libraries full of science texts and encyclopedias, TV sets, airplanes and spaceships" represents a reduction in entropy? Do you? There might be good arguments that such things require a designer, but the 2nd law of thermodynamics is not one of them, because their existence does not violate it.Elizabeth B Liddle
July 3, 2013
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