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Thermodynamics of Life

Origin-of-life studies have been a feature of chemistry for a long time, and over the years some key questions have become clear. It’s clear from astronomical and planetary science data that the common molecules of organic chemistry are more or less soaking the universe. Amino acids and simple carbohydrates are apparently part of the cloud of gunk that makes up a new solar system, with more forming all the time. But a major step is how (and why) molecules would have organized themselves into gradually more complex systems. Some parts of the process may have been modeled already; there are a number of interesting ways that primitive membranes might have formed, which would seem to be a necessary step in distinguishing the relatively concentrated inside of a proto-cell from the more watery outside.
But a new paper (discussed here as well) has a theory that says this might have been flat-out inevitable:

From the standpoint of physics, there is one essential difference between living things and inanimate clumps of carbon atoms: The former tend to be much better at capturing energy from their environment and dissipating that energy as heat. Jeremy England, a 31-year-old assistant professor at the Massachusetts Institute of Technology, has derived a mathematical formula that he believes explains this capacity. The formula, based on established physics, indicates that when a group of atoms is driven by an external source of energy (like the sun or chemical fuel) and surrounded by a heat bath (like the ocean or atmosphere), it will often gradually restructure itself in order to dissipate increasingly more energy. This could mean that under certain conditions, matter inexorably acquires the key physical attribute associated with life. . .
. . .“This means clumps of atoms surrounded by a bath at some temperature, like the atmosphere or the ocean, should tend over time to arrange themselves to resonate better and better with the sources of mechanical, electromagnetic or chemical work in their environments,” England explained.

Self-replication would be an excellent way of doing this, and if England is right, then the development of self-organizing and replicating systems would be “baked in” to thermodynamics under the right conditions. Combine that with the organic chemistry that seems to obtain under astrophysical conditions, and we should, in theory, not be a bit surprised to find living creatures hopping around, full of amino acids and carbohydrates, using sunlight and chemical energy to do their thing.
England’s theory is still fairly speculative, but he seems to be moving right along in applying it to living systems, at least on paper. What I like about this idea is that it would seem to be testable, in both living and nonliving systems. Perhaps something can be done at the level of bacteria, yeast, or even viruses or bacteriophages. I look forward to seeing some data!

37 comments on “Thermodynamics of Life”

  1. haptic says:

    I don’t understand this. If life is inevitable, where are the Martians?
    In the solar system, we know of 5-10, maybe more, planets or moons with an external source of energy (often the sun, but also heat from the interior of the planet) and surrounded by a heat bath (like the ocean or an atmosphere).
    We don’t know for sure whether any of them (besides Earth) have life– its just possible some do. But we do know for sure that (except Earth), the contribution life makes to overall energy balances, if any, is so small it cannot be detected by our most sophisticated instruments.
    In particular, I would guess we know enough about Martian chemistry/geology (marsology?) by now to confirm or deny in fairly short order whether there are complex molecules good at dissipating energy sitting around the surface. My guess is there aren’t, but what do I know.

  2. student says:

    Maybe this should be called entropic catalysis — ie. living things are catalysts for increasing entropy.

  3. Henry's cat says:

    Come on, we all know you Americans are keeping the Aliens and their technology for yourselves…
    I don’t blame you really, after all they always land in the USA in the movies…

  4. Crimso says:

    Nice one. Thanks, I’m now going to discuss this in my topics class this semester (our topic is “Origins of Life”). They know I love thermo (and I’m not being my usual sarcastic self there).
    I see Enrico Fermi reads you and comments as well.
    haptic: “inevitable” doesn’t mean “already happened.” Nor does it mean that because there are older bodies in our solar system for which the same necessary conditions obtain, that those bodies should have already developed life. The thermodynamics is only part of it. The kinetics (and everything that impacts it) of the process is just as important. In effect, things such as oceans, abnormally large satellites, etc. could be considered as catalysts. Not all systems with the “correct” thermodynamics will have the “correct” catalysts, and so those systems might be reasonably expected to take trillions of years for the emergence of life. We might appear to be alone because we are.
    Alternatively, “people don’t shout in jungles.” Think I got that recently from Centauri Dreams. The Centauri Dreams blog occasionally features postings considering origins of life as it relates to exobiology. Lots of cool stuff there, too. Lowe and Gilster are the two science blogs I read nearly every day, and I know I’m missing out on some other good ones.

  5. Gene says:

    @haptic There’s a really good chance there *were* Martians, but Mars doesn’t have a strong magnetic field, and so the Solar wind has stripped most of the original atmosphere, and volatiles like water went with it. Curiosity and the other rovers have showed pretty conclusively that it did have a *lot* of water in the past.
    There is one of the gas planet’s moons with a lot of water, and it’s possible that it does have life. Titan also has a weather system of some sort. Unfortunately, it’s very expensive to get there and look.

  6. Vaudaux says:

    Flat-out inevitable:
    Lots of chemical reactions are thermodynamically favorable, but don’t occur in the absence of a catalyst. More accurately, I guess, is that in the absence of a catalyst they occur only rarely.
    In living cells today, most biochemical reactions must be catalyzed by enzymes, even though they are thermodynamically favorable. Without enzymes, those reactions would still inevitably occur, but on a time-scale that would not be useful to the cell.
    Self-organizing and replicating systems may be inevitable in a thermodynamic sense, yet have so high an energy barrier that they have occurred spontaneously only once (as far as we know) since the beginning of time.

  7. NMH says:

    Where are the martians?
    As Ernst Mayr has pointed out, 99.99% of all species that has ever lived on earth have gone extinct, and humans are the only species ever produced capable of examining the universe around them…and that would have been greatly delayed if it was not for western culture.
    So there may be life on other worlds, but its mostly likely comprised of forms that cannot examine the universe, like slime molds.

  8. Anon says:

    Those in the know say that there’s very little that’s new here. We already know how dissipative structures can arise from the basic laws of thermodynamics (for instance as explicated by Ilya Prigogine). That being said, it’s always nice to know some more details. By the way the paper’s been around on arXiv for more than a year.

  9. haptic says:

    @4,5,6,7
    So, prior to this paper, it was thought by many (most?) that that life is highly improbable, not likely to happen on a timescale of billions of years, and prone to disappear not long after it formed.
    This paper argues that life is inevitable. However, if your interpretation of “inevitable” is correct, inevitable is meant in the thermodynamic sense: it roughly translates as consistent with “improbable, not likely to happen on a timescale of billions of years, and prone to vanish not long after forming.”
    This does not strike me as a profound advance.

  10. Vaudaux says:

    @9 haptic: Exactly.
    As a biologist (who hasn’t read the actual papers), it is not surprising to me that biology is consistent with physics. It is surprising that physicists see this as a new discovery.

  11. Jerry says:

    Sounds like intelligent design to me!

  12. Crimso says:

    haptic and Vaudaux: not exactly. We have no idea whatsoever on what timescale life could be expected to develop (and persist) as we only have one data point. Don’t count me among that “many (most?)” statement. Don’t misinterpret my comment as stating that thermodynamically inevitable means it can’t be fast. Thermo and kinetics are orthogonal. You can interrelate the two, but neither dictates the other. Something can be a virtual certainty to occur according to the thermo, but still require 10^30 years to actually occur. Or it could occur in a fraction of a second.
    Inevitable in the thermo sense and in the context of a snapshot taken at this moment roughly translates as “improbable or probable, likely to take 10^30 years or 10^-6 seconds, and prone to vanishing shortly after forming or persisting for the rest of time.”
    The key point to remember is that we never really had any idea how likely life is to form (again, we have a single data point), and the fact that we detect no life elsewhere leads us to the tempting (and I think probably incorrect) assumption that we are all there is (at least in terms of sentient life). Given the incomprehensibly vast scale of the universe, if life is thermodynamically inevitable, then it probably does exist elsewhere right now, and some of it is probably sentient. It just may be that the sentient life is in another galaxy (or is 10 light years away but using technology we can’t detect, either because its level is too high or too low).

  13. Dr. Manhatan says:

    “If life is inevitable, where are the Martians?” Wiped out in 1898 by bacteria? I thought the historian Herbert G. Wells covered that?
    Seriously, Mars may have had life in the past, or possibly favorable prebiotic conditions were not around long enough. The ability of the Martian atmosphere to block destructive UV (virtually non-existent at present) may have been a factor. As much as I would like to see Curiosity or one of its next generation find Martian life, I personally think that given the conditions at present (high UV, per chlorates etc.) it is unlikely there is current life there.

  14. Anonymous says:

    I wonder if England’s ideas would be testable in a toy chemistry, such as
    http://organicbuilder.sourceforge.net/
    Organic Builder already supports self-replication (challenge 19), very mesmerizing to watch.
    Also: I wonder if England has been introduced to Hutter and Wissner-Gross?

  15. RKN says:

    What I like about this idea is that it would seem to be testable
    First thing I thought, too. I wouldn’t want to be the grad student given this project, though. Might be ABD for a very, very long time waiting for the “inevitable” to occur.

  16. Anonymous says:

    Replying to 15 RKN: Should only take 7 days, tops. Time enough to catch a snooze.

  17. Anonymous says:

    I imagine that key and necessary ingredients for life are appropriate chemicals, appropriate reaction conditions, etc. All the energy in the world will do no good if you don’t have that. So, that we have A and B and a suitable reaction media and energy………

  18. Anonymous says:

    Life anywhere is still not likely. I imagine that key and necessary ingredients for life are still appropriate chemicals, appropriate reaction conditions, etc. All the energy in the world will do no good if you don’t have that. So, that we have A and B and a suitable reaction media and energy………

  19. daen says:

    @3: Henry’s Cat — they don’t always land in the US (https://en.wikipedia.org/wiki/Morons_from_Outer_Space)

  20. alf says:

    I think the term “life” is being stretched here. Self-replication does not necessarily mean life. Crystals self-replicate but most people don’t consider them as alive. The author uses the phrase “key physical attribute associated with life”.

  21. RKN says:

    @16:
    Specifically, I assume you mean 6 days, and snooze on the 7th. 😉

  22. I don’t doubt life is inevitable given enough time. I also don’t doubt that once formed life is precarious. I am far more doubtful of intelligent, human-like life emerging since that seems much more a product of accident.

  23. Yancey Ward says:

    #21
    God was a slacker. He really didn’t need 6 days to get it done.

  24. Anonymous says:

    In regards to this idea that “life” is inevitable, I would warn one to be careful about what is defined as “living”.

  25. Cal says:

    There has got to be a machine learning scheme to be exploited here.

  26. Chemdiary says:

    Also, when we say “life” we think of the life as it is present on earth. But, even the gravity is different on other planets. I hope they are doing experiments on ISS to see how gravity effects chemical and biochemical reactions. So, may be there are other large “molecules” and “systems” on other planets that we don’t understand yet.

  27. Reverend J says:

    @7
    and that would have been greatly delayed if it was not for western culture
    Excuse me? You might be forgetting about a little thing in the past known as the “Dark Ages” Also, I’m sure your algebra wouldn’t be doing to well if it wasn’t for Muhammad ibn MÅ«sā al-KhwārizmÄ« and many other from millenniums before him.
    I’d suggest you’d read some history of science in the world, but it seems you’ve already made up your own fantasy of what has happened.

  28. Anonymous says:

    I’m not sure why this paper/work is supposed to be so groundbreaking…
    Probability of life
    = 1 – (99.999…% probability of NOT creating life in unit time) ^ infinite time
    = 100%

  29. Anonymous says:

    I’m not sure why this paper/work is supposed to be so groundbreaking…
    Probability of life
    = 1 – (99.999…% probability of NOT creating life in unit time) ^ infinite time
    = 100%

  30. Anonymous says:

    27: Excuse you: The scientific revolution occurred in the west; it most certainly did NOT occur in the islamic world. Most scholars agree that we can thank the arabs for translating Greek texts, but that’s about it. Stop trying to rewrite history.

  31. NMH says:

    27: I am aware that important contributions to science and math came from the Middle East, India, and China. That being said, I think, as #30 has may be eluding to, that the work of some early philosophers/scientists in the west (eg Descartes, Newton, Galileo) seemed to start a culture of inquistiveness and curiosity in the west that well-outpaced these trends in other cultures of the world.

  32. Anonymous says:

    …meanwhile other countries still cut your head off or pelt you with stones if you dare to question their faith.

  33. Paul says:

    In particular, I would guess we know enough about Martian chemistry/geology (marsology?) by now to confirm or deny in fairly short order whether there are complex molecules good at dissipating energy sitting around the surface. My guess is there aren’t, but what do I know.
    The interesting recent discovery (

  34. Paul says:

    (for some reason it cut that off)
    The interesting recent discovery on Mars is that the regolith contains substantial quantities of perchlorate. This was unexpected. While this does not rule out the presence of life (and perchlorate solutions can have very low freezing points), it does mean organic materials run the risk of being destroyed by oxidation (either by perchlorates or by the conditions that are creating the perchlorates.)
    The presence of perchlorates also explains the odd Viking lander results, which didn’t see organic matter, except for some small halogenated compounds.

  35. Henry's cat says:

    @19:daen: lol. I thought we were talking about intelligent life? Good film, though.

  36. vulcano says:

    we don’t have warp drive technology yet, hence the vulcans (or other space travellers) are leaving us alone because we are too primitive?

  37. David L. says:

    Being a past student of both Biology and Physical Chemistry, and a current student of Probabilty and Statistics, I’m not sure what to think. On the one hand, billions of years is a long time and having the right chemicals and energy around could create some fantastic systems like life. But on the other hand, even the simplest form of life is so complex I can’t beging to see how you go from a self replicating chemical to a cell structure that can only survive if the entire system is in perfect order. Distrupt one thing and the cell dies. It seems there’s still something very key that isn’t known yet.

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