Boltzmann Brains and evolution

In the “Elon Musk” discussion, in the midst of a whole lotta epistemology goin’ on, commenter BruceS referred to the concept of a “Boltzmann Brain” and suggested that Boltzmann didn’t know about evolution. (In fact Boltzmann did know about evolution and thought Darwin’s work was hugely important). The Boltzmann Brain is a thought experiment about a conscious brain arising in a thermodynamic system which is at equilibrium. Such a thing is interesting but vastly improbable.

BruceS explained that he was thinking of a reddit post where the commenter invoked evolution to explain why we don’t need extremely improbable events to explain the existence of our brains (the comment will be found here).

What needs to be added is that all that does not happen in an isolated system at thermodynamic equilibrium, or at least it has a fantastically low probability of happening there.  The earth-sun system is not at thermodynamic equilibrium.  Energy is flowing outwards from the sun, at high temperature, some is hitting the earth, and some is taken up by plants and then some by animals, at lower temperatures.

It is really the same argument that can be made against Granville Sewell’s nonsensical “Second Law” arguments against evolution.  Sewell makes it sound absurd that random evolutionary particles could form buildings and computers.  He does this by leaving out the intermediate steps where the particles aggregate into atoms, those into molecules, those into rocks, those into planets, and then energy flow from the sun to those planets enables life to exist.  All processes that are far from thermodynamic equilibrium.  Life lives by harnessing some of that energy flow.  All of this has been understood since … well, since Boltzmann.

Boltzmann Brains are too improbable to worry about, but single-celled organisms do develop sensitivity to their environment, involving waves of excitation that involve electrochemical potentials  across their cell membranes.  And when multicellular animals developed, some cells specialized in doing that, leading ultimately to Ludwig Boltzmann’s own brain.

Those processes do not simply result from thermodynamic fluctuations in an equilibrium system.

77 thoughts on “Boltzmann Brains and evolution

  1. And there you have it folks, Joe cleans the table by asserting that life “harnesses” some of that energy flow.

    How is that a better argument than Granville Sewell’s???

    Energy flow says diddly squat about the how and why some molecular configurations can and do harness energy but others don’t.

    Joe, is this your box of chocolates argument?

  2. Sewell makes it sound absurd that random evolutionary particles could form buildings and computers.

    What we know by experience to be designed objects, like computers and autos, don’t just appear without designers being responsible, therefore, what reproduces and carries with it the appearance of evolution–life–was in fact designed.

    It is one of the most backward arguments that I have ever seen. Even somewhat more backward than ID in general, which is the idea that design was required to make life exist with all of the evolutionary constraints and evolutionary patterns of non-design.

    Glen Davidson

  3. Steve: How is that a better argument than Granville Sewell’s???

    Amusingly that means you just skipped most of the OP as that question is answered therein.

  4. Joe,

    I’m the one who first introduced that Redit answer on the Elon Musk thread. But Bruce convinced me that it was a bit simplistic. My first thought, after reading that Redit thing was that the BB argument was missing a ceteris paribus clause in one of the premises. But reading Bruce’s posts on the matter suggested to me that the argument had a different method of getting what it wanted without an “all else equal” coda.

    Our discussion of the matter ended with the following, which maybe you’d like to comment on….

    Bruce:
    Here is a more specific version of my argument.
    Let T = the length of time the universe will exist between the big bang and the start of the heat death.
    Now consider an urn and fill it with balls as follows.
    1. Put in a ball labelled “OB” for each non-overlapping time interval t during T in which a brain with my current thoughts exists. Probably there is just one such interval, but all that matters is that the number of OB balls must be finite (assuming t cannot be made arbitrarily small, which I think is justifiable).
    2. Now consider some interval T* starting at the heat death phase. Put a ball labelled “BB” in the urn for each for each non-overlapping interval t in T* such that there is at least one BB that has the same thoughts as me now in that interval . As T* grows without limit reflecting the fact that the heat death lasts forever, the number of BB balls will grow without limit.
    I say that the situation we are in is analogous to selecting a ball from such an urn. As T* grows without bound, the probability of selecting a BB ball grows arbitrarily close to 1.
    ETA: Since we are living at some specific time, maybe the above is missing steps for each of the two intervals T and T*. First we need to select a time in T and a time in T*, then create the urn with balls up to each time, then we compute the probability of a BB ball being selected from that urn. Something like that. I think I can complete that to fix to the argument, but first I’ll wait and see any thoughts on the scenario so far.
    ***************
    Walto:
    I want to revise my [earlier remarks] here. Trying to come up with an analogous [argument] has given me a better understanding of [the BB argument], I think. I think it DOES have some stuff that substitutes for the clause I thought was missing, viz.:
    1. The universe is a closed system;
    2. For all we know, the universe has existed for an infinite time prior to now;
    3. Infinite time series cannot involve infinite numbers of separate ‘beginnings’ of finite time series.
    With those added, I think the BB advocate indeed has us over a barrel. But I here defer to cosmologists. Doesn’t the currently prevailing theory deny 2 and 3?

    *******************
    Bruce:
    I agree (2) is not the current consensus view, although it was Boltzmann’s, I think, and one source of his original concern (another was no knowledge of evolution).

    Here is a more specific version of my argument.
    Let T = the length of time the universe will exist between the big bang and the start of the heat death.

    Now consider an urn and fill it with balls as follows.

    1.Put in a ball labelled “OB” for each non-overlapping time interval t during T in which a brain with my current thoughts exists.Probably there is just one such interval, but all that matters is that the number of OB balls must be finite (assuming t cannot be made arbitrarily small, which I think is justifiable).
    2.Now consider some interval T* starting at the heat death phase.Put a ball labelled “BB” in the urn for each for each non-overlapping interval t in T* such that there is at least one BB that has the same thoughts as me now in that interval. As T* grows without limit reflecting the fact that the heat death lasts forever, the number of BB balls will grow without limit.
    I say that the situation we are in is analogous to selecting a ball from such an urn. As T* grows without bound,the probability of selecting a BB ball grows arbitrarily close to 1.

    ETA:Since we are living at some specific time, maybe the above is missing steps for each of the two intervals T and T*. First we need to select a time inT and a time in T*, then create the urn with balls up to each time, then we compute the probability of a BB ball being selected from that urn.Something like that. I think I can complete that to fix to the argument,but first I’ll wait and see any thoughts on the scenario so far.

    **************
    Walto:
    I’m not really competent to opine on this, and maybe I just come out with the same response you attributed to someone else above, but my general sense is that all the info that we use to determine the likelihood of the premises in our argument for BB being true are now being used to deduce that those premises are actually false. I.e., I’d think that cosmological theory and other parts of physics–which we seem to be depending on when we make this argument– would seem to be inconsistent with us currently being in a heat death phase. So if the conclusion is correct, we have no reason for believing the premises.

  5. walto:

    Our discussion of the matter ended with the following, which maybe you’d like to comment on….

    I’m kind of embarrassed about putting such a hand-waving argument to someone who has a deep understanding of the probability and its role in science*. But, what-the-hell, I am an not the only one to put forward questionable arguments on TSZ.

    Here is the background as I saw it:

    If we take as given the premises that
    1. There will only be a finite time in our universe before heat death is reached.
    2. Heat death will last forever.
    3. Life is only possible during that initial finite time.
    4. Boltzmann brains have a tiny but non-zero probability of existing at any time, including the infinite time after the heat death.
    5. I am having a subjective experiences which would be described as “I see a tree”.

    Now, given the above, I have the intuition that I am much more likely to be a BB than a “normal” brain existing before the heat death. Can that intuition be captured in a probability argument? I tried to do so in the text Walt quotes.

    —————-
    ETA: Not meant as a backhanded comment on your knowledge of probability, Walt; of that I have neither knowledge nor knowledge*.

  6. No prob. I’m far from knowledgeable on the subject, certainly. I’ve only taken one statistics course. I’ve worked closely with actuaries for many years and I enjoy reading statistics textbooks–but only if they’re intro level.

  7. Steve: And there you have it folks, Joe cleans the table by asserting that life “harnesses” some of that energy flow.

    How is that a better argument than Granville Sewell’s???

    Energy flow says diddly squat about the how and why some molecular configurations can and do harness energy but others don’t.

    Joe, is this your box of chocolates argument?

    https://en.wikipedia.org/wiki/Photosynthesis.

  8. Creationists should drop 2nd law of thermodynamics as an argument against evolution. I’ve taken the side of TSZ regulars against my fellow IDists on the topic.

    I’ve asked a simple question of creationists and IDists which they refused to answer.

    What has more entropy, a frozen dead rat or a living human?

    Answer: a living human has more entropy than a frozen brain dead rat.

    The same sort of question can be posed regarding boltzman brains.

    I provided sample calculations as would be expected of a college chemistry, engineering or physics student in this thread. It’s moderately technical, but someone with a little algebra background can understand it. It’s tedious, but well that’s the nature of physics:

    http://theskepticalzone.com/wp/2lot-and-id-entropy-calculations-editorial-corrections-welcome/

    Some may have wondered why me (a creationist) has taken the side of the ID-haters with regards to the 2nd law. It is because I am concerned for the ability of college science students in the disciplines of physics, chemistry and engineering understanding the 2nd law. The calculations I’ve provided are textbook calculations as would be expected of these students.

    The fundamental problem is 2LOT is concerned with energy (or position/momentum) microstates, whereas IDists are concerned with “design space” microstates. The number of microstates can both be expressed in information bits, but it does not mean we are dealing with the same microstates. I’m providing sample calculations to prove the point that it is disastrous for IDists to invoke textbook 2LOT for the simple reason 2LOT is concerened with energy (or position/momentum) microstates which has little or nothing to do with “design space” microstates of interest to ID.
    …..

    Thanks Joe for the post.

  9. Pure nonsense Cordova!

    Living systems exhibit the ability to control entropy, albeit not indefinitely.

    And reproduction is life’s ace-in-the-hole that restarts the process of entropy control all over again. So even though individual lives finally succumb to entropy, life in general does not.

    So yeah,thanks to fecundity life in general does defy entropy time and time again.

    This is what you can’t (or more likely won’t) wrap your brain around.

  10. Rumraket,

    Photosynthesis is not an answer. It’s just another question.

    That is, what caused collections of molecules to be affected by light in such a way as to be changed into more complex configurations and not others?

    Moreso, how can you talk about any of this in any intelligent manner without reference to design, without reference to viability, survival, purpose?

    So in order for you to avoid this obvious conundrum, you have no choice but to fall back on a rope-a-dope rhetorical strategy.

  11. Pure nonsense Cordova!

    Really? So what has more entropy – a living human with a functioning brain or a frozen rat with its brains removed?

  12. Joe Felsenstein: Steve seems not to get it that organisms require energy to reproduce.

    Long history of that in crypto-creationism. Dembski and Marks (2009) noted in their first published paper, probably at the behest of a reviewer, that simply increasing the size of a uniformly random sample increases the “active information” of the sampling process. I responded with “Work Is Not Information.” Wesley (Elsberry, I presume) left a comment:

    People have been pointing this out to Dembski since at least 1997 at the “Naturalism, Theism, and the Scientific Enterprise” conference where Bill Jefferys of UT Austin socked him with it.

    Dembski and Marks (2010) fixed the problem in their second version of the active information measure, but Dembski, Ewert, and Marks (2013) reintroduced it in the third (current) version. Let’s say you have a non-terminating process that samples uniformly (with replacement), and also an observation process with a “terminator” (DEM’s term) that kills the sampling process when the sample is of size $n$, and with a “discriminator” (DEM’s term) that selects a fittest element of the size-$n$ sample. If the “target” is the set of all individuals of maximum fitness, and not all individuals are in the target, then the probability of hitting the target, and by definition also the active information, is monotonically increasing in $n$. The more work the overall system does, the more “information” DEM say must have been “inputted in its construction.”

    Although this is too abstract for most people (including federal judges), it’s perhaps the simplest way to expose the lunacy of “conservation of information.” DEM sidestep the (in)sanity check by predicating fixed $n$. But they really shouldn’t be allowed to get away with that.

    (I’m well aware that the energy expenditure of a reversible computation can, in theory, be driven arbitrarily low. It never goes to zero, in practice.)

    Sorry if this seems to derail the thread. I didn’t know I’d write so much when I started.

  13. With this comment it seems professor Felsenstein and even Tom English are willfully denying the elephant in the room, are they not?

    It is not the question of organisms requiring energy to reproduce but the ‘need’ to reproduce in the first place.

    From a non-teleological evolutionary perspective, molecules have no foresight, no ability to plan, organize, etc. etc. So science needs to ask what drives certain molecular configurations to absorb light and ‘then something extraordingary happens’ but for other configurations, ‘its a dud’.

    So time and time again, your side is religated to handwaving and dismissive rhetoric with ‘oh, we’re working on it’ and ‘oh, we know lots and lots about what is happening’.

    At least Dembski is brave enough to withstand the design denial community’s petulant and infantile ridicule and barbs and boldy chart a new course to finally break the stale 20th century dogma of ‘its all physics and chemistry’.

    What is so ironic (and satisfying) is to watch the extraordinary lengths design deniers go to to crib off design in order to seam-seal their non-teleological narrative.

    And that is saying alot about the multi-colored, quilted tapestry that non-teleological evolution is in all its glory.

    “Steve seems not to get it that organisms require energy to reproduce.”

  14. Steve:

    At least Dembski is brave enough to withstand the design denial community’s petulant and infantile ridicule and barbs and boldy chart a new course to finally break the stale 20th century dogma of ‘its all physics and chemistry’.

    Actually, Dembski is “brave” enough to bail out of ID, Steve.

    I think he got tired of failing.

  15. Tom,

    The fact that you write so much in opposition to Dembski and Marks to me seems a blatant admission that they are on to something (which offends you in some shape or form). Otherwise, I don’t think you would spend so much time looking for nano-gaps in their caculations.

    Sure criticisms are not a bad thing. It sharpens the senses on both sides of the equation. But you are still on defense. Perpetually it seems.

    So its easy to forget who is in possession of the ball. Hint: Its not Tom English or Joe Felsenstein.

  16. Steve: From a non-teleological evolutionary perspective, molecules have no foresight, no ability to plan, organize, etc. etc. So science needs to ask what drives certain molecular configurations to absorb light and ‘then something extraordingary happens’ but for other configurations, ‘its a dud’.

    It is processes, not molecular configurations, that absorb energy from light.

  17. That is keiths’ characterization.

    Nothing more.

    Dembski has made is point. Information more and more is in fact being seen as an independent entity acting on matter.

    Design deniers are looking more and more like Luddites. Dembski’s work is done here.

    keiths:
    Steve:

    Actually, Dembski is “brave” enough to bail out of ID, Steve.

    I think he got tired of failing.

  18. Random particles could not create computers or buildins.
    So yes evolutionists must say the intermediate steps can see particle to computer.
    Hmm. I agree a computer is less complicated then a single cell or anything biological.
    Yet still these must be mighty steps of chance organization. It boggles the brain.Well mine!
    Single celled things , however excited, coming from and turning into other things is too easily explained away by chemistry.
    Uts saying AGAIN that small steps can explain everything. yet again that means everything. however improbable/impossible. Its not saying anything intellectually about actual origins of/in biology. its just a line of reasoning.
    Evolutionists have got away with this too long or at least in saying this line of reasoning counts as scientific investigation of how things actually happened.

  19. Steve:

    The fact that you write so much in opposition to Dembski and Marks to me seems a blatant admission that they are on to something…

    By your logic: The fact that you write so much in opposition to atheists seems a blatant admission that they are on to something.

    Can’t you think even one step ahead, Steve?

  20. Why is there such a penchant for pedantry on this board?

    It takes a certain molecular configuration to you know…start a process…which has the capability to absorb light….which then triggers other processes in other molecular configurations, which results in work, which results in growth and complexity, which results in LIFE !

    Neil Rickert: It is processes, not molecular configurations, that absorb energy from light.

  21. Tom and I “write so much in opposition to Dembski and Marks” because they put forward mathematical arguments that are supposed to establish that a Designer must have set up the pattern of natural selection that results in adaptation. And because so many fans of ID think that their argument establishes that. But we showed that their argument does not establish that.

    Now exactly what was it that was wrong with our argument, Steve? Be specific, we’re happy to go into details. I realize that you don’t engage in “pedantry” but there is the issue of backing up your arguments. Is it “pedantry” when people ask you to do that?

  22. Steve,

    What I did wasn’t pedantry. I simply took your dumb argument and reflected it back to you so you could see how dumb it was.

    It isn’t a sign of weakness for Joe and Tom to use strong arguments against Dembski and Marks, but it’s definitely a sign of weakness when you use dumb arguments against them.

  23. Steve: It takes a certain molecular configuration to you know

    Why be coy? How did your intelligent designer get that configuration together in the first place? When did it do that? Why then? etc etc. Questions you have never asked yourself nor will ever ask yourself.

    As Joe F notes, you don’t seem to have any substance to your argument. No, you know, science. Don’t you feel any shame at being essentially a literate Robert B? It’s the exact same quality of argument, except you can just string a sentence together somewhat better.

  24. A nitpick I find myself repeating: the harvesting of light is but one, and probably secondary, means of tapping into energy flow. There are plenty of atoms and molecules right here on earth that are not in thermodynamic equilibrium, or rather wouldn’t be if placed in proximity. Place them in proximity and they react – which fundamentally means that electrons shift their allegiance in favour of a lower-energy configuration. Life interposes itself in this process, introducing a ‘stepped’ energy release that intercepts the flow of electron energy, by physical as well as chemical means.

    Each time energy flow happens, with or without a living thing tapping into the flow, the earth as a whole moves a tad closer to complete thermodynamic equilibrium, but such complete equilibrium would take a looooong time, even without a sun.

    This is how chemotrophy works. Provided the electron-accepting molecules are not all consumed, it can go on in near-perpetuity. Light allows for a particular, albeit very successful, means of getting molecules up to the top of the hill, but is unlikely to be primordial. Plenty of atoms and molecules on earth are already there, relative to others at the other end of the slope.

    As to Boltzmann Brains in an equilibrium earth, I don’t see how this could be even possible. The issue is not simply one of random departures from equilibrium for the energy in the system, but requires physical movement of atoms, (or am I talking the ‘brain’ thing too literally?). Brains aren’t made of energy, but of ‘stuff’.

  25. Steve: The fact that you write so much in opposition to Dembski and Marks to me seems a blatant admission that they are on to something (which offends you in some shape or form).

    That’s idiotic. It’s like admitting there’s “something to it” if you vigorously oppose Nazism, or child-rape.

    Maybe it’s opposed because it’s just wrong?

  26. Allan Miller:

    As to Boltzmann Brains in an equilibrium earth, I don’t see how this could be even possible. The issue is not simply one of random departures from equilibrium for the energy in the system, but requires physical movement of atoms, (or am I talking the ‘brain’ thing too literally?). Brains aren’t made of energy, but of ‘stuff’.

    If we consider a closed box of a gas at thermal equilibrium, there is still a tiny but non-zero probability that all the gas molecules will spontaneously move to a state of much lower entropy; eg, all the one half of the box.

    As I understand the BB scenario, it is like that, only more so. Instead of the box, we have the whole universe (but still with atoms in it) at maximum entropy (“heat death”); the low probability configuration that spontaneously occurs is something that briefly functions as a human brain.

    If the heat death happens and lasts for an unlimited time, and if the probability of BB is greater than zero, then intuitively a BB with that briefly goes though the same internal states as I do when I have my current thoughts will occur an unlimited number of times.

    Sean Carroll has more including the reason that Boltzmann started thinking in that general direction.

  27. It’s not always clear to me what is being envisaged when people talk of ‘Boltzmann Brains’. It seems to be a peculiar construct, whereby something observed inside the universe constructed by these hypothetical entities actually obeys the same rules they observe – though only up to a point. In this outer world, physical brains can exist in a gas, but thermodynamics still rules, and there is still such a thing as a gas.

    But why should it reflect any of those internally-observed phenomena? Why should the external reality bear any relation to the apparent reality inside? The same applies to the ‘simulated universe’ idea. It’s like saying ‘Hmmm, a teapot. Hey, I wonder if the universe is inside a gigantic teapot?’. Because, while it may all be an illusion, it’s teapots all the way up?

    The Second Law applies only in our (observed) reality. There is no warrant for invoking behaviour that can be observed in that reality to be operational outside it. IOW, Boltzmann brains are based on a particular, and undemonstrated, assumption regarding the relation between apparent reality and real reality. What reason would we have to suppose that local fluctuations against that internal arrow happen ‘outside’? Or, indeed, that the entire concepts of entropy, energy or matter have any meaning ‘outside’?

    I experience the same reaction to Boltzmann Brains as to multiverses, ‘it’s a sim’ and ‘it’s a hologram’. It all seems like shaky thinking to me.

  28. BruceS,

    If we consider a closed box of a gas at thermal equilibrium, there is still a tiny but non-zero probability that all the gas molecules will spontaneously move to a state of much lower entropy; eg, all the one half of the box.

    Yep, that’s the point though. Sure you can get fluctuations in a gas. It’s a state of matter that lends itself to demonstrating one kind of entropic improbability – more so if you imagine the gas molecules to be ‘ideal’, a box of singularities. But even a gas does not actually behave like that. An equilibrium solid system even less so. Gas molecules get in each others’ way; atoms in solids likewise. When energy has equilibrated in a solid, the energy has departed. The atoms ain’t going anywhere. Sure, they can still ‘randomly’ gain enough energy to move. But everything else is in the way. They can’t configure.

    I think there is an implicit assumption of infinite paths, but there are always likely to be some states, especially compacted ones, that physically cannot be reached from a given start point by simple fluctuations of probability. Including, it is perfectly possible, ‘brains’.

  29. I have the same general impression. We actually have evidence for some stuff–the rest of it is soap bubble possibilites that would, only if occurrent, defeat that actual evidence. We can see that the bare possibility of conflicting scenarios doesn’t matter once we recognize that neither justification nor knowledge requires ‘proof’ or any other species of truth-entailing certainty.

  30. Allan Miller:

    I think there is an implicit assumption of infinite paths, but there are always likely to be some states, especially compacted ones, that physically cannot be reached from a given start point by simple fluctuations of probability. Including, it is perfectly possible, ‘brains’.

    According to 2LT, all molecules moving to one side of a box is not impossible, just highly improbable. That includes highly compacted states or any state as far as I know that is not impossible. Obviously, brains are possible. As Carroll points out in the post I linked, in a heat dead universe you just need to make your box big enough to include all the required molecules and wait.

    ETA: As I understand it, your point is that brain configurations cannot occur spontaneously. Why would that be though? If it is because that would require a lot of events each of which is thermodynamically highly unlikely, then I grant that. It is just more zeros after the decimal point in the probability. But infinite takes care of that, at least intuitively, as long as the joint probability of all the events is not zero.

    Bolzmann actually considered that idea that our entire universe was a quantum fluctuation, although I am not clear on what point in its history he thought it fluctuated into existence. Boltzmann had some pretty good insights into 2LT and its probabilistic basis!

    Carroll argues in the post I linked earlier than BBs are even more likely that entire universes fluctuating into existence.

    Here’s another post from Carroll on BBs; they are taken seriously enough by some physicists that he got a paper published on why they may not be physically possible for a reason related to the Higgs boson. (My point being it takes some complicated physics to try to rule them out, at least not according to the to scientists who take Carroll’s work seriously enough to peer review and publish it).

  31. walto: The point is that it doesn’t need to be.

    I removed that phrasing after about 1 minute of posting it. I invoke the 5 minutes rule with regard to ETA: ie one has 5 minutes after posting to make any change without doing an ETA.

    (I just made that rule up, of course.)

  32. walto:
    . We can see that the bare possibility of conflicting scenarios doesn’t matter once we recognize that neither justification nor knowledge requires ‘proof’ or any other species of truth-entailing certainty.

    I don’t believe a BB in a heat dead universe even perceives, let alone knows.

  33. Me:

    Really? So what has more entropy – a living human with a functioning brain or a frozen rat with its brains removed?

    More relevant perhaps to the OP. According to Boltzman’s definition of entropy

    S = k ln W

    So which has more entropy a brainless amoeba or a human brain according to Boltzmann?

    Answer: human brain has more entropy than a brainless amoeba since

    W_human_brain > W_brainless_amoeba

    As Joe pointed out:

    It is really the same argument that can be made against Granville Sewell’s nonsensical “Second Law” arguments against evolution.

    If it is necessary it INCREASE entropy to make something like brainless bacterium into an organism with a gigantic brain like a human brain, what’s the point of all the lowering entropy arguments of IDists and the 2nd law?

    Answer: 2nd law adds confusion factors since entropy can be increased by increasing temperature and/or adding more particles to a system. An embryo developing a brain requires a thermodynamically open system. As the embryo develops to an adult its entropy increases because the number of atoms in the system increases. If one wants to remove practically all the entropy in a system, freeze it to absolute zero — a lot of good that will do.

    Doubt me? How about supporters of the creationist 2nd law arguments actually provide entropy calculations as would be expected of a college physics, engineering, or chemistry student. Here’s a place to start, and one can make it as complex and exhaustive as one desires, but this is the starting point:

    https://en.wikipedia.org/wiki/Standard_molar_entropy

    In chemistry, the standard molar entropy is the entropy content of one mole of substance, under standard conditions (not standard temperature and pressure ).

    It’s pointless to frame arguments in closed systems at equilibrium, it’s pointless to argue the 2nd law in support of ID. Worse, it’s just plain wrong.

    Where is Kairos Korageous and his fishing reel turbo encabulator arguments when you need him?

  34. BruceS,

    Right. But for our ostensible perceptual experiences to be veridical, we need evidence.

    We have it, and it’s not defeated by the bare possibility of ray guns on Rigel 7.

  35. BruceS,

    As Fernando the duck says in “Babe the Pig”

    “I like that rule. That’s a good rule. But this is bigger than rules!”

  36. FWIW, to appreciate the difficulty of the topic of statistical mechanics and thermodynamics and Boltzmann’s work:

    http://www.eoht.info/page/Founders+of+thermodynamics+and+suicide

    In trivia, founders of thermodynamics and suicide refers to the curiosity that among thermodynamics founders (Mayer, Haber, Lewis, Bridgman), statistical mechanics/statistical thermodynamics founders (Boltzmann, Ehrenfest), human chemical thermodynamics founders and or initiators (Goethe, novel Werther, Adams, his wife, Wieninger, Goethe’s protege), and morphological thermodynamics pioneers (Turing), a curiously large number are associated with suicides or suicide attempts. This coincidence is summarized well by American physicist David Goodstein in the opening lines to his 1975 book States of Matter: [9]

    “Ludwig Boltzmann, who spent much of his life studying statistical mechanics, died in 1906, by his own hand. Paul Ehrenfest, carrying on the work, died similarly in 1933. Now it is our turn to study statistical mechanics.

    In sum, thermodynamics, what many consider to be the most intellectually difficult subjects of all, is noted for its prevalence of suicides and suicide attempts by a large percentage of its founders

  37. For people who like entropy or postings by Sean Carroll, he recently posted at undark on how 2LT and the nature of the universe just after the big bang help make sure wound grandfather clocks in good repair only tick forward (almost all the time).

  38. Bruce,

    For people who like entropy or postings by Sean Carroll, he recently posted at undark on how 2LT and the nature of the universe just after the big bang help make sure wound grandfather clocks in good repair only tick forward (almost all the time).

    He also wrote an excellent book on the topic:

    From Eternity to Here

  39. keiths:
    Bruce,

    He also wrote an excellent book on the topic:

    From Eternity to Here

    Yes, read that and also his latest, which as I think I said earlier, is a fun and fast read, but for what I am interested in sacrifices depth for breadth (but I can understand that Carroll would do that for his intended audience).

  40. Bruce:

    …also his latest, which as I think I said earlier, is a fun and fast read, but for what I am interested in sacrifices depth for breadth (but I can understand that Carroll would do that for his intended audience).

    I read somewhere that he cut a lot out of The Big Picture. Even so, it clocks in at 480 pages!

  41. BruceS,

    According to 2LT, all molecules moving to one side of a box is not impossible, just highly improbable. That includes highly compacted states or any state as far as I know that is not impossible.

    There’s the rub. What’s possible? I think you (and others) are over-extending the graspable model of randomly jiggling ideal gas atoms to cover all systems to which the term ‘thermodynamic’ can be applied.

    If there is one gas atom in a box, obviously it can be anywhere. Two, then there can easily be times when they can both be the same side of an arbitrary divide. Now start adding more and more atoms. Similar applies, with diminishing probability – there is always a nonzero possibility for an ideal gas that all atoms will be one side of your line. But these are real atoms, not ideal ones. You’ve put them in a box, so probably want collisions with the wall to simply change direction. But they still collide with each other, which changes the energy and direction of the interactors. You need all their vectors to point in the same direction, but you can’t get this because of collision. The more atoms there are to collide with, the more the gas will tend to fill the space, and block paths.

    Now, one might agree that, since one can artificially create a circumstance B where all the atoms are on one side, and allow that to go to equilibrium state A, time-reversibiliy means that there must be paths linking equilibrium and non-equilibrium states. But only from that starting point. The fact that B could be achieved from A does not mean that state A will ever exist, even with infinite jiggling. States macroscopically indistinguishable from A may exist, but not A itself. You don’t just need any old A-like macrostate, you need a specific set of microstates.

    This is evidently not-quite-true for smallish numbers of atoms, and one could hope that that glimmer of diminishing probability saves the case as more and more interactors are added to the box. But I think the window becomes closed off completely. Once you start adding interaction, the ideal gas model (and intuitions on order and disorder) become less and less valid. Suppose we have so many ‘gas’ atoms that they create their own gravitational field – the mass of Earth in a teaspoon, that kind of thing. Would it still be possible to get them all on one side of the box, in an infinity of time? How, physically? They can barely move.

    Suppose further, instead of solely considering positional results in a monoatomic gas, our nonequilibrium state requires molecular configurations. If you start with a box full of hydrogen, say, can it ever generate atoms of carbon, oxygen, iron and so on, and molecules made from them, without going through the ‘conventional’ state of collapse and nuclear fusion? Can chemical entropy be defeated by statistical mechanics?

    Obviously, brains are possible. As Carroll points out in the post I linked, in a heat dead universe you just need to make your box big enough to include all the required molecules and wait.

    The bigger, and denser, you make your box, the less work the box model can do – the more interaction interferes and restricts paths.

    ETA: As I understand it, your point is that brain configurations cannot occur spontaneously.If it is because that would require a lot of events each of which is thermodynamically highly unlikely, then I grant that. It is just more zeros after the decimal point in the probability. But infinite takes care of that, at least intuitively, as long as the joint probability of all the events is not zero.

    It is simply assumed that the probability is not zero, by unwarranted extension. Obviously, given that a brain can decay into a higher entropy state, one could imagine that precise reversal of the photon and molecular trajectories could reassemble that state. But it’s not re-assembly that we are talking of. We are talking of an actual state A (which did not arise by decay of B) from which a path must exist to another actual state B, against the thermodynamic rub of the green. And I don’t think the incantation ‘infinity’ helps there.

    Can brains arise through mere thermodynamic jiggling of an atomic assemblage, rather than via stellar nucleosynthesis, supernova, solar disk accretion and evolution? It’s not enough just to imagine that they could.

  42. Allan,

    Even if you reject classical Boltzmann brains, that doesn’t eliminate the possibility of Boltzmann brains due to fluctuations in the quantum vacuum.

  43. Allan Miller:
    There’s the rub. What’s possible?

    I (and Carroll, I guess) are missing something in your argument. After all, brain configurations can exist. The brain in which I am having this thought exists now.
    We are not talking about some state made impossible eg by the gravitational attraction of its components.

    I agree the atoms have to be present. I am talking about the heat death of this universe with its existing atoms.

    I agree that path is against the thermodynamic “rub of the green”.

    ETA: I guess 747s could also exist in heat death, even without junkyards and tornadoes.

    Swampmen without semantic abilities too (for Walt)

    To be clear, nothing in what I am saying has any bearing on the probability of brains in the time before heat death when evolution operates.

  44. keiths,

    Even if you reject classical Boltzmann brains, that doesn’t eliminate the possibility of Boltzmann brains due to fluctuations in the quantum vacuum.

    Well – I reject it thus!

    Is it possible, in an infinity of universes or time? Quantum effects are soon wiped out even when you get up to the atomic scale, let alone the molecular and supra-molecular. I think, in both cases, people are envisioning an infinitely shrinking probability that never gets to zero. But why doesn’t it?

    And the other issue remains – as a Boltzmann Brain of whichever cause, why would I experience, in my illusory perceptual world, the very behaviour which caused my existence in the ‘real outer world’? Quantum fluctuations happen ‘in here’, not ‘out there’.

  45. Now a couple of things that do bother me about BBs:
    Having a thought is a process, not a state, and I don’t know if a BB randomly assembled can exist long enough to have a thought. I guess you have to assume enough of the required biological support to allow the time for that process to occur. Or maybe the sequence events for the process just becomes part of the overall sequence events that has to arise by fluke. Either just amounts to more zeros after the decimal point (in the number giving the probability).

    There is also the issue about what “having the thought means”. If it means a state with some kind of semantic contents (such as “I am a brain have a thought”), I don’t know if a BB can be said semantically capable. Even if it is a BB which duplicates one of the awake sequences of states of Searle’s brain.. Maybe we need to assume enough environment and body to allow perception? More zeroes.

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