Re: 2nd law clarifications

On 2025-01-04 6:44 a.m., MarkE wrote:

On 4/01/2025 12:38 am, Rufus Ruffian wrote:

MarkE wrote:
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On 3/01/2025 5:13 am, Ernest Major wrote:

On 02/01/2025 06:53, MarkE wrote:

Are these statements correct? Could they be better expressed?
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Local entropy can decrease in an open system with an input of free
energy.
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Free energy alone is not sufficient to maintain or further decrease
low local entropy: an energy capture and transformation mechanism is
also needed.

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Capture and transform into what, something useful?
Who defines what's useful?  It's subjective, isn't it?
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The sun beats down on surface rocks in the daytime. They get hot. At
night, the heat spreads downward and evens out the temperature, and
entropy is reclaimed. The entropic tide rises and falls, in a relative
way. Who needs to capture and transform anything?
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Extant life *maintains* low local entropy through its organisation and
processes.

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Life blows through energy like a hungry kid in a mcdonalds, leaving a
trail of entropy in its wake. Even green plants do so.
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You are taking the old "entropy = disorder" meme too seriously. It's
just a simplistic conceptualization. Entropy is the change in system
energy divided by the system temperature. Details at
<https://en.wikipedia.org/wiki/Entropy>
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Evolving life *decreases* low local entropy through the ratcheting
mechanism natural selection acting on random mutations in instances
where that evolution increases functional complexity and organisation.

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How many joules per kelvin are there in "functional complexity and
organization"?
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There is no other known mechanism apart from natural selection that
does this. For example, neutral drift alone increases entropy.

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[citation needed]
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Life generates the entropy it's going to generate, without regard for
anthropomorphic concepts like drift and neutrality, let alone
complexity, let alone "intelligence".  As far as thermodynamics is
concerned, those are not even things. Think joules per kelvin, old
buddy.
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It is difficult to operationalise the concept of irreducible complexity,
as that necessitates a principled definition of system, part and
function. But if you pass over that point, there are at least three
classes of paths (exaption, scaffolding, coevolution) whereby
irreducibly complex systems can evolve. I suspect that the last is the
most frequent, and that it can be driven by drift as well as by
selection. If you are equating an increase in functional complexity and
organisation with a decrease in entropy, then this would negate a claim
that neutral drift always increases entropy.

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What I would say more confidently is, "For example, neutral drift alone
increases disorder."

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It's good to see a man who can be wrong with confidence.
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More precisely, if a population fixes neutral and near-neutral mutations
over time through drift, with no selection acting, the net effect over
time will be devolution, i.e. a loss of information and functional
complexity. The end state will be extinction.

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If devolution happens, it's not exactly neutral, is it?

 You're confusing the relative neutrality of a near-neutral mutation with a cumulative population effect over time.
 

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If a population extincts itself, then mucho selection has occurred, has
it not?
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Again, how many joules per kelvin are consumed by the loss of
"information"?
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Does this necessarily mean entropy will increase? It would seem so.

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No.  Entropy increases because that's what entropy does. It doesn't care
than remarkable life forms are constructed along the way.

 Universally, of course. Locally, not necessarily. Would you agree that evolution produces a local decrease in entropy?
 

I would not agree with that. You need to discard the idea that 'disorder means higher entropy'. My favourite example is rust. Iron rust has a lower "local" entropy that the iron+oxygen that combine to produce it. (see https://www2.oberlin.edu/physics/dstyer/P111/EntropyRust.pdf)
Evolution changes aspects of life but doesn't (locally) reduce entropy. Life (locally) reduces entropy but at the expense of greatly increasing entropy less locally. Think of life as God's way of speeding up the heat death of the universe.
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Don Cates ("he's a cunning rascal" PN)