Talk:Second law of thermodynamics/Archive1

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Subtle distinction in rebuttal to creationists' misuse of the second law

The usual rebuttal to the creationists' bogus claim that evolution violates the Second Law is to say that the earth is not an isolated system and it receives a large amount of energy from the sun. While these two statements are both true, it doesn't really refute the claim.

The change of entropy of an object is defined as the amount of heat energy transferred in or out of the object divided by the temperature at which the transfer occurs. If heat flows out of the object, then the object's entropy decreases. So it is not correct to say that the entropy reduction on the earth is enabled by a larger entropy increase on the sun, because the sun's entropy actually tends to decrease as it radiates energy and the solar energy that hits the earth tends to increase its entropy.

What actually happens is more subtle. The earth is radiatively coupled to two "objects": the sun and the rest of the universe. As we know from the physics of global warming, the thermal power the earth receives from the sun at optical and infrared wavelengths must equal the outbound radiation of thermal power at long infrared wavelengths or the earth heats or cools until the radiation balance is restored. This power balance satisfies the first law of thermodynamics, the conservation of matter/energy.

But the earth is much warmer (300 K) than most of the sky (3 K, the cosmic background temperature) so that the decrease in the earth's entropy associated with the radiation of each unit of heat energy is much less than the resulting increase in the entropy of the universe as a whole.

So it is actually more correct to say that the reason life can evolve and survive on the earth is that solar energy flows through the earth from a very hot source (the sun at 5785 K) to a very cold sink (the rest of the universe). This is analogous to how the high temperature heat from burning fuel flows through a gas or steam turbine, producing useful work plus low-temperature waste heat that must be dumped into the environment. Just as a heat engine cannot run without both fuel and a heat sink, life on the earth could not survive without both the sun and the rest of the universe into which to dump its low-temperature waste heat energy.

Karn 03:39, 21 June 2007 (CDT)

Indeed, feel free to edit. MiddleMan 09:54, 21 June 2007 (CDT)

Hmn

This edit is not exactly clear to me. Are you defining the universe to cover what is necessary to make it an isolated system? If so, you could just say "The universe is defined in such a way that it is an isolated system." Heart♥Gold^{Swarm like a hive} 12:12, 17 July 2007 (CDT)

No, because that's not how it is defined, although the definitions are equivalent. The universe is in laymen's terms: everything there is, all space, all energy there is is stored in the universe. MiddleMan 12:17, 17 July 2007 (CDT)

Okay, if that is not how it is defined, you should be able to cite a reference that prooves the universe is an isolated system. Or is this pseudoscience? Heart♥Gold^{Swarm like a hive} 12:19, 17 July 2007 (CDT)

No, there is no space-time (yes, no time) outside the universe, so heat currents cannot flow there. MiddleMan 12:21, 17 July 2007 (CDT)

Original research on your part, definitional, or can you cite a scientific proof to this effect? Heart♥Gold^{Swarm like a hive} 12:36, 17 July 2007 (CDT)

Another

Again, this edit is not exactly clear to me. Couldn't the Earth also gain potential energy, e.g., the creation of mountain ranges? Heart♥Gold^{Swarm like a hive} 12:19, 17 July 2007 (CDT)

Well I suppose the better way to say it is that high-grade energy from the sun interacts with the earth, where some of it is stored and eventually released as low-grade energy into space. But the creation of mountain ranges is not fueled by the sun, thats storage of energy from the core and mantle. Most of the sun's energy that gets stored is stored in plants/bacteria or trapped as heat. tmtoulouse ^oppress 12:35, 17 July 2007 (CDT)

Hence, my comment (somewhere) about being integrated (and by implication) averaged over time. Heart♥Gold^{Swarm like a hive} 12:38, 17 July 2007 (CDT)

Assume I am ignorant of all previous discussion (which I am)...what are you attempting to integrate? tmtoulouse ^oppress 12:39, 17 July 2007 (CDT)

The energy into and out of Earth. Heart♥Gold^{Swarm like a hive} 13:04, 17 July 2007 (CDT)

So you mean integration of the difference between the energy entering the earth and leaving the earth? That gets exceedingly complicated depending upon what exactly you are looking at. Sources of external energy include extra-terrestrial objects, and extra-terrestrial sources of radiation, the bast majority of that is not "stored" in the earth and just continues on unchanged. So if we only look at external energy thats stored I would say that currently it would currently integrate to a positive number since there is plenty of "stored" energy left. However, as we let the time axis expand eventually we would integrate to 0 if we only count energy released that was originally stored from external sources. But if you want to count ALL energy that will ultimately be released the difference between energy in and energy out will ultimately be negative since the earth has its on energy left over from its formation that will eventually be released...............but why does this matter? tmtoulouse ^oppress 13:12, 17 July 2007 (CDT)

I think it is actually possible to store potential energy in the Earth like that, it would however be insignificant, and extra energy is far more likely to manifest itself as kinetic energy or heat. Not that the influx has to equal the outflux to make Earth an open system. MiddleMan 13:09, 17 July 2007 (CDT)

Hmmm... I'm going to have to work on this a bit at some point. In the world of chemistry, people are moving away from the misapplied term "disorder" to "degree of dispersion of energy." It turns out the disorder analogy isn't such a good one, and a lot of the social analogies are even worse. ŠтΈṜȳŁЁ^and...? 13:12, 17 July 2007 (CDT)

Yes the order/disorder stuff is problematic, I usually respond to creationist attempts at using 2nd LOT by asking them what the rules governing transfer of heat have to do with evolution anyway? tmtoulouse ^oppress 13:20, 17 July 2007 (CDT)

Exactly; in chemical terms how the quanta of energy are always distributed statistically among the energy at equilibrium; it's just when two systems interact, they need to redistribute that energy. Hence why all energy ends up as heat. All gen. chem books (or at least the decent ones) have in their last edition taken out a lot of (if not all of) their references to disorder, and certainly the messy room or desk analog. It's been acknowledged that 40 years of chemical pedagogy were all crap. ŠтΈṜȳŁЁ^and...? 13:28, 17 July 2007 (CDT)

"It turns out the disorder analogy isn't such a good one, and a lot of the social analogies are even worse." Bad social analogies are not caused by actual words used, in my opinion. It just happens. See social darwinism and the eugenics movement. Heart♥Gold^{Swarm like a hive} 21:25, 17 July 2007 (CDT)

You mean that Einstein and Fermi were wrong, because people turned their ideas into weapons of mass destruction? MiddleMan 21:28, 17 July 2007 (CDT)

Rewrite

Sterile, I would like to put the example of the room and some other things back in. So, a curious homeschooler can understand how entropy works and what is actually meant by "disorder". Not that there's anything factually wrong with your version, but it might a bit hard to follow for laymen. MiddleMan 21:22, 17 July 2007 (CDT)

Go ahead--I was worried it was a bit "elevated." You will find I'm not particularly possessive about most articles. ŠтΈṜȳŁЁ^and...? 10:31, 18 July 2007 (CDT)

How come nobody ever says...

...that evolution disproves the second law of thermodynamics? I think we should be told. Totnesmartin (talk) 13:24, 14 July 2010 (UTC)

Surely 'the attempt to get everybody to improve so they can go to heaven' violates the second law of thermodynamics?

The laws of thermodynamics refer to generalities rather than particularities within the generality. 82.198.250.70 (talk) 17:11, 11 January 2011 (UTC)

Absurdity of SLOT Argument

I got to thinking about the "SLOT rules out evolution" story and realized a rejoinder: "If the SLOT rules out evolution, then it also must rule out airplanes, cars, and personal computers -- after all, it's not like WE can violate the SLOT either. If the SLOT rules out evolutionary constructions, what's different about human constructions that gives them a free pass?"

This seems like a pretty solid argument to me -- indeed, it's so obvious I can't believe nobody ever thought of it before -- but so far the reaction has been heavily negative. Nobody will tell me why. MrG 71.208.38.224 (talk) 17:48, 19 March 2011 (UTC)

Time to rustle up reliable sources, if it's Wikipedia you're after trying to change. There ought to be some to find in the various rebuttals of objections to evolution. ISTR many of the objectors have a hard time distinguishing open systems from closed ones, which is relevant to second law arguments. Good luck! Sprocket J Cogswell (talk) 18:25, 19 March 2011 (UTC)

No, actually, I'm just running across people to get feedback. I've never been all that happy with the "open versus closed" argument, not because it's wrong, but because it implies some comprehension of thermo, and people who have some comprehension of thermo don't buy the creationist argument in the first place. I think there's something to be said for showing that the creationist argument is silly on the face of it. However, again, the reaction has been generally negative to that idea, I know not why. MrG 71.208.38.224 (talk) 18:33, 19 March 2011 (UTC)

Are you speaking of something like the paragraph in this article that begins:

"Let us suppose that there actually were some process in nature which violated the second law of thermodynamics. Is that any reason to suppose that intelligent designers are responsible?"

TomS TDotO (talk) 18:51, 19 March 2011 (UTC)

Yeah, it's the same idea, phrased a bit less vividly than I would put it. (I didn't *think* I could have been the first person to think of the idea.) But do you have a source on that? MrG 71.208.38.224 (talk) 18:59, 19 March 2011 (UTC)

Because humans are intelligent and airplanes, cars, and PCs are therefore Intelligently Designed^TM. SLOT only applies to things that are not intelligent. /creationist logic Actually, I like this argument, but I'm not a physics guy so I'm not sure if it applies. Nebuchadnezzar (talk) 19:02, 19 March 2011 (UTC)

Yeah, that's the obvious answer, but the response is obvious too: "Nobody's ever been intelligent enough to figure out a way to violate the SLOT. Creationists are saying it is impossible to break the SLOT -- now they're saying somebody's broken it?" MrG 71.208.38.224 (talk) 19:09, 19 March 2011 (UTC)

Expanding misuse of the SLOT

I encountered a creationist on Xbox live who astounded me with his lack of understanding of SLOT. He tried to claim it as a basis for why comets could not possibly exists in a deep timeline scale. I think that the misunderstanding had something to do with him reasoning that the dispersal of heat over so much time would raise the temperature of the frozen material. Too bad for him that the universe is a lot bigger than he apparently thinks it is, and heat presumably not working the same way he thinks it does. I think that this is the gist of what the person said, but I may not have presented it right, which would be irrelevant considering that the original argument was outright wrong.

If anyone gets to this, can they tell me if they have encountered it before and how common it is?--JabberwockDownTheHole (talk) 01:54, 11 July 2011 (UTC)

a Bronze is really in teh "best of?" really?

Seems to me our best of, should be gold or at least silver quality. --GodotMoi j'dis, laisse beton 02:29, 16 November 2011 (UTC)

Best of is a rather old category from back in the day. Тy^talk 02:31, 16 November 2011 (UTC)

entropy always increases

What is the difference between this and "entropy never decreases?" I am but a layman, forgive my ignorance. It's just that I've always seen it as always increases rather than the converse--. 00:03, 21 November 2011 (UTC)

It is possible for entropy to remain constant. Тy^talk 00:08, 21 November 2011 (UTC)

But wouldn't any amount of entropy eventually increase? Because it's entropy?--. 00:26, 21 November 2011 (UTC)

In the universe itself, yes. Тy^talk 00:37, 21 November 2011 (UTC)

So it can't remain constant, then, right?--. 00:41, 21 November 2011 (UTC)

Entropy basically falls out of a statistical equation to do with states (among a few other things). Because of this it's only a statistical effect, really. Entropy is very likely to increase, highly unlikely to stay the same, and almost impossibly to decrease within a closed system. See: wp:Ergodic hypothesis and wp:Poincaré recurrence theorem ^theist 00:44, 21 November 2011 (UTC)

The major qualification is within a closed system. An energy flow through the system is apt to decrease the entropy within the system (such as the energy pouring in from the Sun onto the Earth and the radiation from the Earth into space). BTW, this is not a violation of the 2nd law of thermodynamics, but is part of the expression of the law. TomS TDotO (talk) 11:59, 21 November 2011 (UTC)

But the universe itself is a closed system by definition. Entropy in the universe always increases (or could stay the same) but at the same time it could go on forever to the point where it could statistically rearrange itself to have order again. There are some problems with assuming this means the universe will repeat itself out of statistical certainty, but it adds an extra layer of complication to how much the law really is "inviolable". ^gnostic 14:37, 21 November 2011 (UTC)

I was always under the impression that when scientists decide to call something a "law," that at that point it was incontrovertible. Is this not the case here? I ask because of Armondikov's first post--. 02:29, 24 November 2011 (UTC)

Mostly laws are statements of observed relationships. Think of Snell's law (about the refraction of light when passing between two different media), or Ohm's law (about electric circuits). TomS TDotO (talk) 12:02, 24 November 2011 (UTC)

Pseudo-science in the American Journal of Physics

On February 27, 2012, the following article was accepted by the American Journal of Physics for review. I have some criticisms of the RationalWiki article too. I consider the second law of thermodynamics just as much a law of physics as Newton's second law.

Evolution and the second law of thermodynamics (manuscript ID no. 25055)

The articles published by the American Journal of Physics, “Entropy and evolution” (November 2008) and “Evolution and the second law of thermodynamics” (October 2009) are based on a lack of understanding of thermodynamics and evolutionary biology.

The common descent of species refers to the evolution of mammals from bacteria over a period of 3 billion years. Adaptation refers to the evolution of traits that increase the chance of survival in the various habitats that cover Earth. While there is no easy way to draw the line between adaptation and common descent, natural selection is a theory that explains only adaptation. It does not explain common descent. In other words, natural selection explains why giraffes have long necks, but it does not explain how giraffes evolved from fish and fish evolved from prokaryotes.

I have I a license to teach physics in New York State and can lawfully teach biology if no licensed biology teacher is available. I would give my hypothetical class the following two quotes to support the above assertion. The first quote should be read slowly. The second quote is from a biologist who I think limits the explanatory power of natural selection more than most biologists:

Facilitated variation is not like orthogenesis, a theory championed by the eccentric American paleontologist Henry Osborn (1857–1935), which imbues the organism with an internal preset course of evolution, a program of variations unfolding over time. Natural selection remains a major part of the explanation of how organisms have evolved characters so well adapted to the environment. (Marc Kirschner and John Gerhart, The Plausibility of Life: Resolving Darwin’s Dilemma, 2005, page 247)

P. falciparum, HIV, and E. coli are all very, very different from each other. They range from the simple to the complex, have very different life cycles, and represent three different fundamental domains of life: eukaryote, virus, and prokaryote. Yet they all tell the same tale of Darwinian evolution. Single simple changes to old cellular machinery that can help in dire circumstances are easy to come by. This is where Darwin rules, in the land of antibiotic resistance and single tiny steps…There is no evidence that Darwinian process can take the multiple, coherent steps needed to build new molecular machinery, the kind of machinery that fills the cell. (Michael J. Behe, The Edge of Evolution: The Search for the Limits of Darwinism, 2007, p. 162)

The following is a quote from a science writer who thinks natural selection does explain the complexity of living organisms. You might ask the author what biology textbook or peer-reviewed article she got this idea from. Christine Kenneally, Steve Pinker, and Paul Bloom have PhDs in linguistics, not biology.

They [Pinker and Bloom] particularly emphasized that language is incredibly complex, as Chomsky had been saying for decades. Indeed, it was the enormous complexity of language that made is hard to imagine not merely how it had evolved but that it had evolved at all....But, continued Pinker and Bloom, complexity is not a problem for evolution. Consider the eye. The little organ is composed of many specialized parts, each delicately calibrated to perform its role in conjunction with the others. It includes the cornea,…Even Darwin said that it was hard to image how the eye could have evolved....And yet, he explained, it did evolve, and the only possible way is through natural selection—the inestimable back-and-forth of random genetic mutation with small effects…Over the eons, those small changes accreted and eventually resulted in the eye as we know it. (Christine Kenneally, The First Word: The Search for the Origins of Language, 2007, pp. 59–60)

This is the kind of misinformation the two American Journal of Physics articles are promoting. According to the second law of thermodynamics, an isolated system of non-interacting particles will either be in equilibrium or go to a state of greater disorder. In other words, nature goes from the more complex state of speed and location to the less complex state. The two articles report scientific calculations showing that evolution does not violate the second law of thermodynamics. Laymen interpret this to mean that natural selection explains the complexity of life.

A very understated measure of the complexity of life is the primary structure of a protein. A large protein has 600 amino acids connected together. Sickle cell anemia is caused by one amino acid in hemoglobin not being the right one, there being 20 different kinds of amino acids. Evolutionary biologists calculate the probability of getting the primary structure of a protein by the random selection of amino acids. They relate this probability to the time available for evolution, which is 3 billion years. I selected the number 600 because that is the length of an English sonnet, which is made up of approximately 20 letters. Professors Gerhart and Kirschner discuss the chances of getting an English sonnet from the random selection of words and letters in their award-winning book cited above.

These are the same calculations of probabilities used in statistical mechanics to relate microscopic variables to the macroscopic variables of thermodynamics. For example, the connection between temperature (T) and the average kinetic energy (KE) of a molecule in a gas is given by KE = (3/2)kT, where k is the Boltzmann constant. The two articles use an equation connecting entropy (S) with a quantity called thermodynamic probability (Ω): S = klogΩ.

This means there is a loose connection between evolution and thermodynamics. One might say:

Considered thermodynamically, the problem of neo-Darwinism is the production of order by random events. (Ludwig von Bertalanffy, “Chance or Law,” in Beyond Reductionism: New Perspectives in the Life Sciences, The Macmillan Company, 1969, page 76)

However, the idea that evolution violates the second law of thermodynamics is irrational because the second law is as certain as saying the odds of getting snake eyes in a dice game is 1/36. It is equally irrational to try to prove evolution doesn’t violate the second law by performing entropy calculations on living organisms. It is like calculating the entropy of a deck of playing cards with Boltzmann’s constant. A deck of playing cards has neither entropy nor temperature.

There are more quotes from mainstream biologists in my Youtube video titled, “The Truth About Evolution and Religion.”

Also of interested to any teacher should be the dialog between me and a graduate student at Berkeley majoring in biophysics: http://www.quora.com/Should-scientists-refer-to-evolution-as-a-law-instead-of-a-theory/answer/David-Roemer-1

This is a link to an article by a mathematics professor that criticizes the two articles. The article itself contains three other links that may be of interest: http://www.evolutionnews.org/2011/10/more_philosophical_than_scient052441.html ^{— Unsigned, by: Davidmihjn / talk / contribs}

tl;dr summary of the above: the author is a religious creationist/cdesign proponentist.--ZooGuard (talk) 12:33, 1 March 2012 (UTC)

Intelligent design and creationism

Concerning ZooGuard's statement that I am an advocate of ID and creationism:

The conflict between mainstream biologists and creationists (also advocates of intelligent design) is a conflict between atheists (and liberal Christians) and Protestants. I call it a conflict because it is not a disagreement between intelligent people about evidence. Protestants and atheists both fail at the level of intelligence. Their cognitive abilities don’t rise to the level of reflective judgment. Ordinarily, intelligence is a measure of how long it takes someone to grasp a concept, insight, or theory. In the case of religion, there is so much conflict, anxiety, and bias that people are inhibited from thinking intelligently. They can’t grasp concepts no matter how much time they have.

I went to a Catholic college and am not an advocate of intelligent design or a creationist. There is nothing in the article being considered by the American Journal of Physics that promotes intelligent design or creationism. If I don't get an intelligent response to my talk comment, I'll proceed by submitting a critique of the RationalWiki entry. Most of what I have to say is in my talk comment. Davidmihjn (talk) 02:36, 2 March 2012 (UTC)

I'm not a physicist. I'm not a biologist. But there is one significant problem; you suggest that nature is some how isolated and closed. Six words "Big yellow thing in the sky". I'm just saying..... ^{— Unsigned, by: WaitingforGodot / talk / contribs} 03:11, 2 March 2012 (UTC)

Also, if you don't want to be mistaken for a creationist, it's best not to quote proponents of said position at length in your arguments. Nebuchadnezzar (talk) 04:08, 2 March 2012 (UTC)

who said isolated or closed ? meteors, gas diffusion into space, the SUN ! its hard to miss the effects of the freaking sun. Hamster (talk) 05:36, 2 March 2012 (UTC)

It's hard to right a response, intelligent or otherwise, to your post, because it's so incoherent, convoluting disorder, complexity, and entropy, and really not considering energy at all. All attempts to consider entropy without energy inevitably fail (aleit sometimes they are framed in terms of configurations of molecules, but not in the way that you do). Any DNA sequence, natural or not, the genes will be expressed to the primary sequence of a protein, as long as the catalysts are present, and is consistent with the second law of thermodynamics. The entropy calculations, properly framed in terms of energy, do show that the entropy decrease by all of life is well offset by the increase by the sun, and you do nothing to disprove that. It's not even clear that your post is a criticism of the papers, as it doesn't even consider them. We welcome criticism, but if it's like this, there's no content to it. (I also suspect Poe here.) Is this you? And this? It is! sterile^talk 05:38, 2 March 2012 (UTC)