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Question: Is it true that free energy increases don't happen naturally? Keep reading for background on what is meant by "naturally".

The idea that a decrease in entropy, even a local one, requires some kind of intelligence or life to make it happen has been around for awhile, and still pops up (for example, Local decrease in entropy, does it require life?). People produce numerous counterexamples. The counterexamples don't impress the person making the claim. "Of course I don't mean that kind of entropy decrease". The goalposts shift. The claim becomes unfalsifiable.

But intelligent design advocates have a new and improved version of the claim, which they use as an argument against naturalistic origins of life. Actually, it has apparently been around since the 1980s, but I haven't seen it addressed by anyone outside the pro-intelligent design community. And it sounds specific enough that it is either true or false.

Here's the improvement. Instead of claiming that a decrease in entropy requires intelligence, they say that an increase in free energy requires intelligence, at least through the introduction of a "machine" or "engine" to act as an energy transducer. The idea is that energy input from the surroundings without a transducer to guide it is "raw" and is therefore disruptive or destructive of order (the phrase Bull in a China Shop comes up frequently). A typical statement is found in this article from Brian Miller of the Discovery Institute, Free Energy and the Origin of Life: Natural Engines to the Rescue

In previous articles, I outlined the thermodynamic challenges to the origin of life and attempts to address them by evoking self-organizing processes. Now, I will address attempts to overcome the free-energy barriers through the use of natural engines. To summarize, a fundamental hurdle facing all origin-of-life theories is the fact that the first cell must have had a free energy far greater than its chemical precursors. And spontaneous processes always move from higher free energy to lower free energy. More specifically, the origin of life required basic chemicals to coalesce into a state of both lower entropy and higher energy, and no such transitions ever occur without outside help in any situation, even at the microscopic level.

Attempted solutions involving external energy sources fail since the input of raw energy actually increases the entropy of the system, moving it in the wrong direction. This challenge also applies to all appeals to self-replicating molecules, auto-catalytic chemical systems, and self-organization. Since all of these processes proceed spontaneously, they all move from higher to lower free energy, much like rocks rolling down a mountain. However, life resides at the top of the mountain. The only possible solutions must assume the existence of machinery that processes energy and directs it toward performing the required work to properly organize and maintain the first cell.

And a similar statement is found in Miller's article, Thermodynamics of The Origin of Life

The problem for all theories of origin of life now becomes quite evident. The simplest functional cell compared to its most basic building blocks has both lower entropy and higher energy. And, natural systems never both decrease in entropy and increase in energy at the same time. Such an event would be like rolling countless sixes in a row when the dice are strongly loaded against rolling even one. Therefore, the origin of life through purely natural processes would seem as implausible as water on a hot summer day spontaneously freezing or a river flowing unaided uphill for thousands of miles.

So, my question is whether the claim is true. Namely, that free energy never increases in "natural" systems without outside help. Or more specifically, that there is never an increase of energy and a decrease of entropy at the same time without the help of some "machines".

I can of course come up with examples where a "machine" is used to raise free energy. For example, a battery drives a chemical reaction "uphill" in an electrolytic cell. And when I asked Miller to explain this claim in the comments section of a youtube video, he simply pointed to the example of a freezer making ice on a summer day. I'm not sure where the free energy increase is involved there, but I guess the basic point is that a temperature difference is created where there wasn't one before, and that temperature difference is a source of available work. I asked him twice for more justification of the claim, but so far he's declined to give it.

Those two examples don't clearly demonstrate to me that a general principle is at work. So, is the principle true or false? Can it be proved from the Second Law of Thermodynamics? Can a counterexample be produced?

I am not asking if intelligent design/creationism is true. I am not asking if a local decrease in entropy can happen.

ether
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    Crystals (highly ordered) form naturally. Arguing with creationists is useless. – Jon Custer Mar 28 '22 at 00:59
  • @JonCuster true, but read the rest of it. – ether Mar 28 '22 at 01:01
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    Again, arguing with creationists is useless. They will just move to some other nonsense. Many natural processes are more bizarre than thy can imagine, much less admit. – Jon Custer Mar 28 '22 at 01:10
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    @JonCuster I don't argue with them to convince them of anything. The point is for me to learn something new. This claim regarding free energy is new to me, and I'd be interested to know the answer. – ether Mar 28 '22 at 02:30
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    First thing to remember is that the Earth is not an isolated system, what with that sun thing shining. – Jon Custer Mar 28 '22 at 02:35
  • @JonCuster That is correct. How does that address the claim that free energy can't increase without "machines"? – ether Mar 28 '22 at 02:51
  • Because the sun is pumping energy into the system, making random assertions about the ‘free energy’ moot. – Jon Custer Mar 28 '22 at 02:55
  • @JonCuster My question is not whether creationism is true. It is whether the claims about free energy increase are true. – ether Mar 28 '22 at 03:06
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    @ether The Sun is a low entropy energy source. Please see https://physics.stackexchange.com/q/399463/123208 – PM 2Ring Mar 28 '22 at 05:36
  • @PM2Ring Thank you, that was very interesting. Doesn't directly address my question, but it is of course relevant. – ether Mar 29 '22 at 02:11
  • @JonCuster I'll rephrase one of my earlier comments. Are you actually saying that the claims are false and that impinging sunlight does raise free energy? Because that is what I think is true. I'd just like to hear it from someone smarter than me. – ether Mar 29 '22 at 02:13
  • @ether - without the sun, the surface temperature of the Earth would be a balmy 35K or so ( see https://earthscience.stackexchange.com/questions/9210/what-is-the-current-equilibrium-surface-temperature-of-earth-i-e-without-the-s). I’d say sunlight makes a pretty big difference in what chemistry occurs here. – Jon Custer Mar 29 '22 at 02:21
  • @JonCuster Can you please just give a direct answer instead of hinting around? I get that the sun makes a difference. You don't have to convince me of that. – ether Mar 29 '22 at 02:34

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The most fundamental counter-argument I can think of is fairly simple. Thermodynamics by its very definition describes the behaviour of equilibrium states (typically local). The living organism is definitely out of equilibrium so you cannot make simplistic claims about entropy or free energy. It is very typical that energy and matter fluctuations lead to the formation of high-density regions in your system: stars and planets in cosmology or cells and living organisms on lower length scales. To apply the thermodynamic reasoning you have to look at the times far greater than the equilibration time (which for the earth are stupendously large). And in the (very) long-term there is no life, only the heat(entropy?) death of the universe.

SmallPieceOfBread
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  • I get what you are saying, I think. That, technically, definitions like temperature and entropy and free energy are defined at equilibrium, and that anything living is far from equilibrium. Nevertheless, real scientists do try to calculate thermodynamic quantities for biomatter. So just saying thermodynamics doesn't apply doesn't really answer the question. – ether Mar 29 '22 at 02:41
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    In biomatter, you look at the intermediate timescales where the chemical reactions reach an equilibrium but at times much shorter than the half-life of stable compounds. Simply, you have to be very specific to formulate the statistical ensemble and building a philosophical argument out of context seems unproductive to me. – SmallPieceOfBread Mar 29 '22 at 08:00
  • Those are good points. Ignoring any philosophical arguments, is it true or untrue that free energy of a system only decreases in "nature"? Is it true or untrue that there is never an entropy decrease and an energy increase in a system at the same time in "nature"? That's really all I need to know. – ether Mar 30 '22 at 01:17
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    The laws of thermodynamics hold statistically - they are about probability. It is incredibly unprobable that in a closed system the entropy will decrease. Strictly speaking, it is possible but the probability of that is less than marginal.

    Similarly, in a system at a fixed temperature, it is incredibly improbable for the free energy to increase. You always have to note the limitations of your statistical ensemble.

     – SmallPieceOfBread Mar 30 '22 at 06:46
  • Right, I understand that fluctuation theorems set bounds on the probability of a entropy decrease in an isolated system. However, I think even a single cell is macroscopic enough to make the statistical aspect unimportant. For the case of a system in contact with an isothermal reservoir, I'm less sure. What about my example of an electrolytic cell? The reaction is driven in the direction of increased free energy (considering the voltage source to be external to the system). What is special about that setup so that a free energy increase is no longer improbable, but practically certain? – ether Mar 31 '22 at 03:25
  • I am not sure if I understand your example, so maybe you could elaborate on that. If I understand it correctly then it comes to the trade-off between two terms in free energy $F=U -TS$. By applying external voltage you increase the energy cost of the disorder making the first term more important. The decrease in the entropy is balanced by the decrease in the energy. – SmallPieceOfBread Mar 31 '22 at 06:09
  • Well, in the example I was actually thinking of, electrolysis of water at STP, the entropy actually goes up a lot (165 J/K per mole) because gas is being produced. But the energy/enthalpy goes up enough (286 kJ/mol) so that the first term dominates. $\Delta G^o = 237$ kJ per mole of reaction. There might be other electrolytic cells where entropy decreases. I'll have to look into it. Either way, here we have a system maintained at constant temperature whose free energy increases. So that can't always be fantastically improbable. The question is, was the human intervention of... – ether Apr 01 '22 at 05:12
  • setting up the electrochemical cell apparatus essential? Or can similar processes take place "naturally" (with nobody's help)? – ether Apr 01 '22 at 05:15
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    Correct if I am wrong here. I think you're comparing the free energy before the voltage is applied and the free energy at the end of the reaction - this is not how it works. You have to compare the free energy in the same external conditions - after the voltage is applied. Then you not only have the energy of the reaction but also the interaction of the water dipole moment with the electric field. – SmallPieceOfBread Apr 01 '22 at 05:55
  • Also, your analysis shows why this reaction does not happen without the external voltage - because it would lead to an increase in the free energy. – SmallPieceOfBread Apr 01 '22 at 06:05
  • I hadn't considered the energy of the dipole moment in the field. That is very interesting. Is that interaction energy considered part of the system internal energy (where the system is just water, hydrogen, and oxygen gas)? And is it large enough to cancel out the positive free energy change? – ether Apr 01 '22 at 06:14
  • And I was comparing free energy right after voltage is applied and stabilizes to free energy at end of reaction. So no change of external conditions. Although that may already provide a partial answer to my question. Free energy increases may well be common when a change of external conditions is allowed. – ether Apr 01 '22 at 06:27
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    This is actually a little more complex. For this system, you would minimize the Gibbs free energy instead of the free energy $G(T,p,E,N) = U(S,V,P,N) - TS + pV + EP$ where $E$ is the electric field and $P$ is the total dipole moment of the system. The fundamental thermodynamic relation for this system is: $U = TS - pV - EP + \mu N$ or in the differential form $dU = T dS - p dV - E dP + \mu dN$. – SmallPieceOfBread Apr 01 '22 at 06:31
  • Ok, I see there is a way to define a thermodynamic potential for the problem, but wouldn't the ordinary Gibbs free energy, G = U+pV-TS still increase? – ether Apr 01 '22 at 06:36
  • Let us continue this discussion in chat. – SmallPieceOfBread Apr 01 '22 at 06:41