TheFallibleFiend

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You have made a horrible mistake

You have invited general inquiries on the subject of thermodynamics. It has been more than two decades since I studied thermodynamics and I am trying to explain it - not explain 'it', necessarily, but explain 'around it' with a few caveats. It's bizarre, but I observe that people often explain things that they don't understand very well - why should I upset the apple cart? So I have a thought about the use of terminology. It's really a very general comment relating to how terms are used by specialists (scientists) and lay people (among whom I count myself); however, the same comment applies between specialists in different areas. My comment is very obvious: If I want to apply a scientific principle, I have to use the appropriate scientific definitions of any terms. Specifically, I see people using words like order in describing and applying certain thermodynamic principles - and I'm pretty sure they are not using the word correctly. I have an analogy that I think helps to draw the distinction I'm trying to make - but I would like to know if my distinction is correct or if my example would be more confusing and less accurate than what's already been said (or worse, outright wrong). I explain the specifics here [1]. Thanks for any feedback. TheFallibleFiend 20:59, 24 July 2007 (UTC)

Thermodynamics is my favorite subject. I’m presently (slowly) building the biggest collection of thermodynamics books and textbooks in the world (I’m almost at 150). Anyway, I read your blog and I previously read Robert Shapiro’s “energy-driven networks of small molecules afford better odds as the initiators of life” article last week. I’ve pretty much read every origin of life book there is. I see that your basic question is that you want to know how the laws of thermodynamics explain evolution, with emphasis on the entropy (order and disorder) paradox. The long and the short of the answer is that evolution is a series of chemical reactions, as the following table shows:

Molecular Evolution Table (shows the evolution from the hydrogen ion molecule to the human molecule)

In thermodynamic terms, the two driving forces involved in these reactions are the enthalpic force (the effects of the first law) and the entropic force (the effects of the second law). These two forces compete with each other. The sum effect is that these two forces drive (evolve) the process in question onto points (configurations) of equilibrium (energy wells of stability); at which time the process ceases to function (change subsides), but in a way in which the process is punctuated and the reactions are energetically coupled to each other.

These isothermal, isobaric, substrate-attached reactions, driven by gamma-ray photons, emanating from the sun, entering the earth at the Karman line boundary at 1340 watts per meters squared, on a periodic basis (i.e. only half of the earth is lit up at any given time), operate according to the laws of thermodynamics (not just the second law):

File:Solar-gradient.jpg

The solar system from a thermodynamic systems perspective.

For a (constant-temperature, constant-pressure) chemical reaction to proceed, there must be a negative change in the Gibbs free energy for the reaction. This is called the combined law of thermodynamics, and it takes into account the effects of first, second, and third law of thermodynamics.

For a species of land-walking fish to evolve into a species of reptiles, for instance, the coupled (million year) reaction process will occur if there is a decrease in the free energy of the system, i.e. the evolution reaction occurred owing to long-term energy stabilizing effects in the system.

This is just the quick and the short answer. Always remember that evolution is nothing but the results of movement of nuclei, (outershell) electrons, and photons. Thermodynamics is simply a way to quantify the movements through calculus. There's a new two-volume textbook coming out next month on the topic of Human Chemistry (with focus on the thermodynamics of human life), which has a chapter on molecular evolution, will likely clarify all the confusion for people around the world. Also check out entropy and life.

To summarize, by example, according to Ingo Muller, from his new 2007 book A History of Thermodynamics, “thermodynamics has uncovered the precarious balance between determinism and stochasticity which is essential to the processes on earth, including life.” He continues (from the back cover), “the competition of those intentions is described by the doctrine of energy and entropy in thermodynamics”, which summarizes nicely as:

“ Energy tends to force a system into one single state, and entropy tends to spread the system evenly over all possible states. These competing tendencies are weighted by temperature such that minimal energy determines cold systems. ”

Later: --Sadi Carnot 22:39, 24 July 2007 (UTC)