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Freddie deBoer used to blog at, and may again someday. Now he blogs here.

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26 Responses

  1. Avatar Will Wilson says:

    1. Baryons are strongly interacting. Things that interact strongly (especially electromagnetically) are easier to notice.

    2. I think I get what you’re asking here. My first, very short attempt at an answer would be: ordered things (in the thermodynamic sense) are inherently more useful than disordered things; so there is a reason why our sense of usefulness and the thermodynamic sense of order are well-aligned.

    The reason ordered things are more useful is that disordered things are basically defined as un-useful. The whole point of the laws of thermodynamics is that heat energy cannot be recovered.Report

  2. Avatar Will Wilson says:

    To clarify point 2:

    One can conceive of a state of the constituent matter of a teacup that would be less “useful” than shards of porcelain but less entropic. That is, our sense of usefulness and the thermodynamic sense of order are not perfectly aligned ab initio. What remains true, however, is that it will be easier to convert the less entropic, less useful state of the tea cup into something useful than it will be to convert the more entropic, more useful state.Report

    • Avatar Freddie in reply to Will Wilson says:

      The reason ordered things are more useful is that disordered things are basically defined as un-useful. The whole point of the laws of thermodynamics is that heat energy cannot be recovered.

      Right. I mean, part of my point is that I think the difference between saying “Entropy means that systems tend to move from states that require higher energy to attain to states that require less energy to attain, hence a tea cup requiring less energy to become porcelain shards” and saying “entropy means that systems naturally tend to drift from order towards chaos” is entirely semantic. But I interpret a lot of casual explanations of thermodynamics to be resting on the idea of order qua human notions of practicality, use, etc. To me, the tea cup is only more ordered than the shards in the sense that it requires a higher energy state to get to the form of the tea cup. The definition of order, in other words, is not a function of human practicality.

      But I take what you mean in saying that it does seem to be the case that there are certain inherent attributes of higher-energy-requiring states that make them more likely to be useful.Report

      • Avatar Will Wilson in reply to Freddie says:

        Well, I think that’s because there is an equivalence between thermodynamics and human notions of practicality. Put it this way: whatever you want to do with the constituent atoms of a tea cup, it will always be easier to do it if they’re in teacup-form as opposed to porcelain shard-form.Report

        • Avatar Freddie in reply to Will Wilson says:

          Ah, see, there we disagree, which is why I invoke the idea of a non-human intelligence. Though I can’t imagine a use for porcelain shards that is greater than a use for a teacup, I can imagine that some alien intelligence could find porcelain shards more useful than a teacup. And it’s in that sense that I think appeals to use are too anthropic; natural laws aren’t concerned with human notions of use. Or so it seems to me. This is part of my discomfort with some “layman’s terms” descriptions of entropy, like the clean room/messy room example. (I say that of course as a layman myself.)Report

          • Avatar Will Wilson in reply to Freddie says:

            I think you misunderstand me. Whatever your alien intelligence wants to do with the constituent matter, it’s almost certainly going to be easier to do it, in terms of energy usage, with the less entropic state.Report

  3. Avatar Will Wilson says:

    Final clarification: “Easier” in terms of energy expenditure.Report

  4. Avatar Bayesian says:

    re number 1 –
    First, what Will said about baryons and certain leptons being strongly interacting with photons, which describes most of the human scale phenomenal universe; e.g. some sudden variation in the strong force or especially the weak force with different properties but which somehow or other still produced similar isotope distributions up through the binding energy minimum at iron wouldn’t change much of biochemistry or climatology, assuming the total heat flux from radioactive decay wasn’t different).

    Second, if (present guesses at aggregate mass-energy, e.g. Lambda-CDM) dark matter/dark energy were to be distributed with uniform density throughout the universe, the effect on condensed matter states would be far below present and perhaps imaginable detection threshold.Report

  5. Avatar Michael Drew says:

    To me, the tea cup is only more ordered than the shards in the sense that it requires a higher energy state to get to the form of the tea cup. The definition of order, in other words, is not a function of human practicality.

    Exactly right. I think you’ve got this one licked. It’s not that the teacup is less useful when in shards that relates at all to the Second Law. It’s just that it spontaneously goes from cup state to that state, but never the other way round. The Second Law is the descriptive rule we’ve induced to explain why it goes that way. Certainly human utility does not come into play into that induction — though it does when we introduce valued terms like “broken” and “chaos” (in the folk meaning of the term) to describe various states, which given our proclivities tends to happen very quickly and get baked into our thinking pretty inextricably. But I think the thinking behind thermodynamics is pretty well free of our human purposes, even if the laws initially began to be developed in the context of industry.Report

  6. I enjoyed your posting.

    Baryons require leptons to communicate using photons. The only forces are represented by the bosons. I have an elaborate theory that examines the interactions of forces without the use of gravity. It also explains Dark Energy and Dark Matter and how they interact with Baryonic Matter without the use of gravity. Gravity is a construct that uses volume-less matter to describe interactions using attraction. Mass breaks laws of mathematics, I explain this at my blog.

    By demanding gravity, physics confuses everybody. Just because you cannot parrot back entropy as physicist demand does not mean that the model is correct or your understanding is incorrect. I don’t think the 400 year old model of attraction is correct. And physicist have fewer reasons to believe Newton’s model is correct. Remember it is only a theory.
    Aaron Guerami

  7. Avatar Murali says:

    As Nav said, S = k ln (W)
    where k is the boltzman constant and W is the no of microstates and S is entropy.

    In a very real way, S measures the messiness of a macrostate. A macrostate which has one microstate (one way of arranging the particles) has an entrpy of 0. While a macrostate with many microstates has a high entropy and is considered messy.

    However the second law of thermodynamics doesnt say that entropy in closed systems always increase.

    What the second law says is that the free energy of a system (open or closed) will decrease

    dG = dH – TdS < 0

    From the equation you can see that when dS increases, dG decreases

    Where G is Gibbs free energy
    H is the enthalpy of the reaction. (energy used/released in changing potential energy. e.g bond formation(-ve) bind breaking(+ve) )
    T is temperature in Kelvin
    d refers to an infinitesimal change
    S is entropy
    Free energy is the propensity to do work (in the force multiplied by distance sense).

    Even in closed systems entropy can decrease. Consider an initial state with chlorine atoms in an isolated box at room temperature. This is a closed system. What will happen is that the chlorine atoms will very quickly pair up to form chlorine gas. Their entropy is approximately half of what it initially was. Even so the free energy has still decreased, because the energy lost from bond formation overwhelms the decrease in entropy.

    As we can see from the 2nd law, temperature acts as a multiplier to the entropy. Therefore even though the change in entropy between the 2 macrostates is still the same, at high temperatures, the entropic effects overwhem the enthalpy changes (even though enthalpy also doesnt change)

    We would considser entropy only if we were looking at inert particles in closed systems. Even then, the messiness of the result is not always immediately apparent.

    In inert colloids, depletion forces (which are entirely entropic in origin) cause lage particles to clump together. This would reduce the number of microstates for large partticles considered alone, but for the small particles in the mixture, the extra space (and therefore entropy) that they gain from the clumping of the large particles more than compensates for the loss of entropy by the large particles. Therefore, entropy increases. However, what people observe is that the dispersed particles areaggregating together. This makes it seem that it is becoming more ordered when it is not.Report

  8. Avatar Katherine says:

    In other words, people talk as if there is something inherently more ordered about the cup in the state of a cup than the cup in the state of hundreds of shards of porcelain. That is, that the cup as a cup is more ordered not simply because it takes more energy for it to be put into a cup than put into shards, but because of some sort of inherent “order” to the cup taking the cup shape. To me, that’s applying human attitudes to the fundamental states of the universe in a way that I find unscientific. The universe doesn’t give a shit about the cup being capable of holding water.

    The way one physics book I read put it is that the more different patterns there are that something can exist in, the more entropy there is. Thus, a liquid has more entropy than a crystalline solid because the individual atoms are free to move relative to each other. Likewise, for the cup, when it is broken there are more individual arrangements possible for the pieces. For the intact cup, there is only one possible arrangement of its pieces: the shape of the cup. Hence, when it breaks, entropy increases.Report

  9. Avatar Alex says:

    “The universe doesn’t give a shit about the cup being capable of holding water.”

    Forgive me, because your whole post is about removing the humanity from the science, but I have to ask you if you are implying that the universe doesn’t have a purpose? Doesn’t it seem, at least if you follow the astronomical and geological and biological history of our solar system, that everything that happens is so that life can exist? Doesn’t the unique value of gravity, when couple to the unique speed of expansion of the universe, combined with the bizarre twist that asteroids are a good water delivery mechanism to proto-planets, combined with orbits, moons (and phases) all seem like the universe was carefully drawn up with mathematical formulas that would inevitably lead to living organisms? Doesn’t the bizarre pseudo-polarity of water, with its low melting point and evaporating point, with its freely donated hydrogen atoms, the ease with which is separates into a hydroxide ion for hydrolysis reactions, the way it can store so much thermal energy per pound, all seem like water was…planned? And if water was planned, why not the teacup to hold it?

    I know this is off-topic, to be sure, but everything I have learned about science tells me that since the Big Bang the Universe has done everything it can to produce teacups, or at least the creatures that drink from them.Report

    • Avatar Freddie in reply to Alex says:

      I’m speaking merely in the specific and limited sense of talking about regarding a loss of practicality as a measure of the increase of entropy. The broader issues that you mention are of course important, just a bit bigger than I have the capacity to untangle.Report

    • Avatar Will Wilson in reply to Alex says:

      Hmm… interesting thought. I wrote some time ago about how the theory of structurally stable singularities could be used to support a teleological view of the universe. I wonder if entropy could be worked into that?

      Thanks for guaranteeing that I will get NO work done today.Report

    • Avatar Jaybird in reply to Alex says:

      It strikes me that this is the equivalent of having a blind guy shoot a shotgun at a barn wall, then drawing circles around each little hole and then asking “what are the odds that he would have shot here, here, here, here, here, here, here, here, here, here, here, *AND* here???”

      We’re looking at it after the fact.

      The theory that “it’s all a bunch of stuff that happened” has equal explanatory power.Report

      • Avatar Alex in reply to Jaybird says:

        Or having a blind guy shoot a shotgun at a barn wall and it makes the perfect outline of a teacup, and then we call it “all just a bunch of stuff that happened.”Report

        • Avatar Jaybird in reply to Alex says:

          For small definitions of “perfect” that are co-extensive with the constellation Leo looking like a perfect outline of a lion.Report

          • Avatar Alex in reply to Jaybird says:

            So I should concede that because Leo the Lion as a constellation is a farcical idea, so too is the idea that the Universe has a purpose? That relies on the idea that Leo the Lion as a constellation is a farcical idea, definitively not intentionally placed in the night sky, which is obviously unprovable.
            My argument is not that God intentionally drew on His holy Whiteboard all the important equations of the Universe and then set it into action, merely that the Universe’s fundamental laws, from gravity to atomic forces to the properties of water, all seem, when coupled with astronomical and geological history and looked at as a whole, very ideally suited for the development of biological life.
            Just because humanity has always seen method to the madness does not mean it is a whimsical idea.Report

            • Avatar Jaybird in reply to Alex says:

              Nope, not at all. Reach whatever conclusion you’d like. I’m not a fan of telling other people how to live their lives.

              I’m just saying that “nothing” is an argument with equal explanatory power.

              From my perspective, there’s nothing but static on the television. This group over here is laughing and saying they are watching Green Acres. That group over there is laughing and saying they are watching Mr. Ed. Every now and again, they argue about it and someone ends up dead. It still looks like static to me.Report

              • Avatar Alex in reply to Jaybird says:

                But the television exists!Report

              • Avatar Jaybird in reply to Alex says:

                As does Green Acres and Mr. Ed.

                But there’s just static.

                Additionally, the television was created by John Logie Baird. Green Acres was created by Jay Sommers. Mr. Ed was created by Walter R. Brooks.

                The patterns in the universe that you are matching are not patterns that I see… or, like Leo, patterns that seem deliberately imposed upon chaos (the teacup shotgun pattern that someone else says is a bunny with short ears).

                I’m not saying that they aren’t there. Sure.

                I’m just saying that I don’t see them.Report

              • Avatar Alex in reply to Jaybird says:

                So are you saying that if you saw a freshly mowed lawn, but not someone mowing it, then you would assume that the grass had, by chance, all grown at to the exact same height at the exact same time? Not that someone had planned the lawn to appear that way? Which is more likely, a yard full of grass the exact same height, or a person, not visible, that recently mowed?Report

              • Avatar Jaybird in reply to Alex says:

                It’s more analagous to a field of flowers.

                You’re saying that they are more beautiful than solomon in all his glory.

                I’m just seeing a field of flowers.

                If the lawn were truly freshly mowed, we wouldn’t be having this argument.Report