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Tim Tyler · Guest

Jim Menegay <jamenegay@ra.rockwell.com> wrote or quoted:
[quote]Tim Tyler <tim@tt1lock.org> wrote in message news:<bsnrbo$ul6$1@darwin.ediacara.org>...

The main link between evolution and thermodynamics which I have
considered is the one that regards evoultion as a dissipative
structure that maximises the level of energy degradation in a system.
[/quote]
[...]

[quote]The idea has been floating around for a long while now. I was first
alerted to it by:

"Life as a Manifestation of the Second Law of Thermodynamics" - Schneider,
E.D, Kay, J.J., 1994, Mathematical and Computer Modelling, Vol 19,
No. 6-8, pp.25-48. [link in references on site below]

I have my own expression of the idea - at:

http://originoflife.net/bright_light/

The thing is, though, that Prigogine>s "dissipative structures" are
claimed to *minimize* the generation of entropy, at least as measured
per unit volume. Your ecosystems are claimed to *maximize* entropy
generation. No one that I have read has ever reconciled these ideas
to my satisfaction.
[/quote]
You are talking about Prigogine>s "principle of minimum entropy production"?

If so, the resolution seems relatively simple:

``The principle of minimum entropy production by Prigogine states that the
rate of internal entropy production (diS/dt) is a minimum for a
non-equilibrium stationary state not far from the equilibrium. For small
deviations or fluctuations around a stationary state, the rate of
entropy production can only decrease with time (i.e., its time
derivative is negative), so that the stationary state with the minimum
rate of entropy production is re-attained. On the other hand, while in
the stationary state, the time derivative of the rate of entropy
production is zero. [...]''

- http://www.geocities.com/riturajkalita/irrevtherm.htm

Prigogine>s principle applies to states which are very near to
equilibrium. An example would be close to universal heat death.

When you are very near to equilibrium, the rate of increase of
entropy is normally very low - since there are few energy gradients
for dissipative processes to feed off - and so the rate entropy
production is low at such locations.

That doesn>t contradict the ideas I mentioned above - about
living systems getting better and better at dissipating energy
gradients by using increasingly sophisticated technology to
extract energy from environmental sources - and using the
resulting resources for making copies of their genes.
--
__________
|im |yler http://timtyler.org/ tim@tt1lock.org Remove lock to reply.

TomHendricks474 · Guest

<<
One idea might be that life is economical in its dissipation of
neg-entropy locally (K-selection?), but that it tends to increase
the volume of the dissipative structure (r-selection?). I just
wish that someone would tie together all of these ideas that are
floating around out there into some kind of explanatory framework!

Jim >>

I think you are trying to make this too complicated when in truth it is
wonderfully elegantly simple.

1. Chemicals react to heat.
out of these
2. Those that have heat dumping strategies are selected
out of these
3. Those that use the heat before they dump it for any supportive purpose are
selected
out of these
4. Those that use some of that heat to raise temp when it is too low to
maximize enzymes are selected. (energy moderators at both ends)
out of these
5. When two chemical systems have equally good thermal stability the one with
other advantages as well is selected.
out of these
etc.
This is adaptation just like every other aspect of life. I don>t think we
should bring in new rules in this area. Adaptation to the environment has
always been the key to evolution - it is here too IMO.

Jim Menegay · Guest

Tim Tyler <tim@tt1lock.org> wrote in message news:<bstkpq$2n7i$1@darwin.ediacara.org>...
[quote]Jim Menegay <jamenegay@ra.rockwell.com> wrote or quoted:
Tim Tyler <tim@tt1lock.org> wrote in message news:<bsnrbo$ul6$1@darwin.ediacara.org>...

The main link between evolution and thermodynamics which I have
considered is the one that regards evoultion as a dissipative
structure that maximises the level of energy degradation in a system.

[...]

The idea has been floating around for a long while now. I was first
alerted to it by:

"Life as a Manifestation of the Second Law of Thermodynamics" - Schneider,
E.D, Kay, J.J., 1994, Mathematical and Computer Modelling, Vol 19,
No. 6-8, pp.25-48. [link in references on site below]

I have my own expression of the idea - at:

http://originoflife.net/bright_light/

The thing is, though, that Prigogine>s "dissipative structures" are
claimed to *minimize* the generation of entropy, at least as measured
per unit volume. Your ecosystems are claimed to *maximize* entropy
generation. No one that I have read has ever reconciled these ideas
to my satisfaction.

You are talking about Prigogine>s "principle of minimum entropy production"?

If so, the resolution seems relatively simple:

``The principle of minimum entropy production by Prigogine states that the
rate of internal entropy production (diS/dt) is a minimum for a
non-equilibrium stationary state not far from the equilibrium. For small
deviations or fluctuations around a stationary state, the rate of
entropy production can only decrease with time (i.e., its time
derivative is negative), so that the stationary state with the minimum
rate of entropy production is re-attained. On the other hand, while in
the stationary state, the time derivative of the rate of entropy
production is zero. [...]''

- http://www.geocities.com/riturajkalita/irrevtherm.htm

Prigogine>s principle applies to states which are very near to
equilibrium. An example would be close to universal heat death.

When you are very near to equilibrium, the rate of increase of
entropy is normally very low - since there are few energy gradients
for dissipative processes to feed off - and so the rate entropy
production is low at such locations.

That doesn>t contradict the ideas I mentioned above - about
living systems getting better and better at dissipating energy
gradients by using increasingly sophisticated technology to
extract energy from environmental sources - and using the
resulting resources for making copies of their genes.
[/quote]
I wrote incorrectly.

You are right in pointing out that Prigogine>s theorem only applies
near equilibrium, and hence does not apply directly to "dissipative
structures" and does not directly contradict the theory that you
and Kay are promoting. Nonetheless, it is quite a stretch to go
from "minimization is unproved" to "it maximizes!".

Your metaphor of "burning bright" vs "burning long" is a good way
to frame the question. Whichever form of burning takes place, in
a living system or a non-living system, the laws of thermodynamics
are upheld. If you have a fixed flux of negentropy to deal with, it
doesn>t matter whether the system is living or dead - all of that
negentropy will be dissipated. The only interesting question is,
if you have a mixed system of living and non-living dissipators,
how will they divide up the task of dissipation among themselves, and
how will this division-of-labor change (evolve) over time. It is
certainly to be expected that the living components of the system
will sieze for themselves a larger and larger role.

But it is far from clear to me that in doing so, they are maximizing
anything, nor does it seem obvious to me that they are "burning bright".
In a steady state, they consume only the fuel that is provided. It
seems to me that they are "burning long".

Tim Tyler · Guest

Jim Menegay <jamenegay@ra.rockwell.com> wrote or quoted:

[quote]You are right in pointing out that Prigogine>s theorem only applies
near equilibrium, and hence does not apply directly to "dissipative
structures" and does not directly contradict the theory that you
and Kay are promoting. Nonetheless, it is quite a stretch to go
from "minimization is unproved" to "it maximizes!".
[/quote]
I never started from "minimization is unproven" in the first place ;-)

Historically, it was more like wanting to characterise the evolutionary
process in thermodynamic terms, seeking out existing material on the
subject, identifing common themes - and then presenting my own summary.

When looked at from a thermodynamic perspective, living systems appear
to be a continuation of self-organising systems. Both feed off
energy gradients to create local order - at the expense of global
disorder.

Living systems tend to be better at doing this that inanimate
self-organising systems - and tend to get better at doin it over time.

[quote]Your metaphor of "burning bright" vs "burning long" is a good way
to frame the question. Whichever form of burning takes place, in
a living system or a non-living system, the laws of thermodynamics
are upheld. If you have a fixed flux of negentropy to deal with, it
doesn>t matter whether the system is living or dead - all of that
negentropy will be dissipated.
[/quote]
Hmm. I would suggest that the second law says entropy doesn>t usually
decrease - not that it will reach the maximum possible value.

Anyway, I>m mostly concerned with how rapidly the disorder arises -
and whether the introduction of living systems speeds up the process.

[quote]The only interesting question is, if you have a mixed system of living
and non-living dissipators, how will they divide up the task of
dissipation among themselves, and how will this division-of-labor
change (evolve) over time. It is certainly to be expected that the
living components of the system will sieze for themselves a larger
and larger role.
[/quote]
Yes, that>s basically what I>m saying.

[quote]But it is far from clear to me that in doing so, they are maximizing
anything, nor does it seem obvious to me that they are "burning bright".
In a steady state, they consume only the fuel that is provided. It
seems to me that they are "burning long".
[/quote]
IMO, they may be doing something a bit in between - though I
suspect they currently do a lot more "burning bright" than they
do "burning long".

I don>t see evolution as being anything like a "steady state" system.

Interestingly, modern humans tend not to hold off "burning" available
energetic resources becasue they are trying to conserve them for the
sake of their descendants - but because they have not (yet) developed
the insulation needed to protect their immediate environment from the
resulting exhausts, and they don>t (yet) have the infrastructure to be
able to utilise a lot of energy very rapidly.

I>m sorry you>re less-than-completely convinced by my characterisation of
evolution as progressively increasing the rate of increase of entropy,
(when averaged over an extended period of time) - and thus my
characterisation of living systems as "burning increasingly brightly".

I /do/ still think that this is the best way of characterising how
the evolutionary process is developing in thermodynamic terms.

It is stimulating to wonder how far the process can be taken:

Will living systems learn how to make stars go super-nova -
in their quest to get extract the available energy in a
system before their competitors do?

Maybe that>s what>s really happening when we see those exploding
suns out there - fireworks that aliens have lit before retiring
to a safe distance from where they can appreciate the results.
--
__________
|im |yler http://timtyler.org/ tim@tt1lock.org Remove lock to reply.

William Morse · Guest

jamenegay@ra.rockwell.com (Jim Menegay) wrote in
news:bsv5vr$51r$1@darwin.ediacara.org:

[quote]Tim Tyler <tim@tt1lock.org> wrote in message
news:<bstkpq$2n7i$1@darwin.ediacara.org>...

You are right in pointing out that Prigogine>s theorem only applies
near equilibrium, and hence does not apply directly to "dissipative
structures" and does not directly contradict the theory that you
and Kay are promoting. Nonetheless, it is quite a stretch to go
from "minimization is unproved" to "it maximizes!".

Your metaphor of "burning bright" vs "burning long" is a good way
to frame the question. Whichever form of burning takes place, in
a living system or a non-living system, the laws of thermodynamics
are upheld. If you have a fixed flux of negentropy to deal with, it
doesn>t matter whether the system is living or dead - all of that
negentropy will be dissipated. The only interesting question is,
if you have a mixed system of living and non-living dissipators,
how will they divide up the task of dissipation among themselves, and
how will this division-of-labor change (evolve) over time. It is
certainly to be expected that the living components of the system
will sieze for themselves a larger and larger role.

But it is far from clear to me that in doing so, they are maximizing
anything, nor does it seem obvious to me that they are "burning
bright". In a steady state, they consume only the fuel that is
provided. It seems to me that they are "burning long".
[/quote]

Lotka in 1922 theorized that the criteria for natural selection was the

[moderator>s arghhh: ARGHHH! Not "criteria": CRITERION. Don>t they teach
Greek any more? - JAH]

maximization of power for useful purposes. And in order to transform
energy to work at the fastest rate, 50% of it will be wasted as entropy
(I am paraphrasing Odum>s 1971 "Environment, Power and Society" in all of
this). Thus living dissipators will maximize the _rate_ of energy
utilization, rather than maximizing the total energy utilization, which
would minimize the rate of entropy production. As far as I can tell, you
are correct that once all of the available energy has been converted to
heat the total entropy production will be the same in any case.

Yours,

Bill Morse

Tim Tyler · Guest

William Morse <wdmorse@twcny.rr.com> wrote or quoted:

[quote]Lotka in 1922 theorized that the criteria for natural selection was the
maximization of power for useful purposes. And in order to transform
energy to work at the fastest rate, 50% of it will be wasted as entropy
(I am paraphrasing Odum>s 1971 "Environment, Power and Society" in all of
this). [...]
[/quote]
Lotka was who Eric Schneider and James Kay credited with the idea
originally. They wrote:

``Lotka>s (1922) suggestion that living systems will maximize their energy
flow, H. T. Odum>s (1955) maximum power principle for ecosystems and
Lieth>s (1976) maximum energy conductivity are all subsumed and
explained by our theory.''

[Lotka, A. Contribution to the Energetics of Evolution. Proceedings of
the National Academy of Sciences USA; 1922; 8: 148-154.]''

- http://www.fes.uwaterloo.ca/u/jjkay/pubs/Life_as/text.html
--
__________
|im |yler http://timtyler.org/ tim@tt1lock.org Remove lock to reply.

Jim Menegay · Guest

William Morse <wdmorse@twcny.rr.com> wrote in message news:<bt48bf$1o0q$1@darwin.ediacara.org>...
[quote]Lotka in 1922 theorized that the criteria for natural selection was ...

[moderator>s arghhh: ARGHHH! Not "criteria": CRITERION. Don>t they teach
Greek any more? - JAH]

Dear Mr. H,[/quote]
I have a datum to offer in response to your question. My eldest son
recently graduated with a degree in classical studies. Unfortunately,
he discovered that his knowlege of Greek and Latin was unmarketable,
and he was forced to seek employment selling vacua door-to-door. He
now scratches out a living as one of the street media catering to the
tourists in lower Manhattan. He should have gotten his degree in
electra-ics.
Perplexed in Peoria

[moderator>s huzzah: Huzzah! If you could have worked in my remaining
three betes noires (to wit: modification of "unique", as in "somewhat
unique"; use of "begging the question" to mean "raising the question";
use of "hopefully" -- and I know this is a lost cause -- to mean "I
hope" or "It is to be hoped", as in "Hopefully it won>t rain", instead
of its real meaning) I would have known that you are, in fact, my
late father-in-law. I suppose the evolution of usage is fair fodder
for this group, for shizzle, my nizzles. - JAH]

Tim Tyler · Guest

Jim Menegay <jamenegay@ra.rockwell.com> wrote or quoted:

[quote]The thing is, though, that Prigogine>s "dissipative structures" are
claimed to *minimize* the generation of entropy, at least as measured
per unit volume. Your ecosystems are claimed to *maximize* entropy
generation. No one that I have read has ever reconciled these ideas
to my satisfaction.
[/quote]
I found a nice description by someone else of how Prigogine>s
idea dovetails with the "maximum power principle" I>m advocating:

``the Minot-Aoki law has had two well-known descendants: the
Lotka-Odum maximum power principle (Lotka 1922, Odum and
Pinkerton 1955) and the Prigogine minimum entropy production
principle (Prigogine 1955), in which production diminishes
to a steady state near system equilibrium.

The interpretation given here (Salthe 1993) is that, because the
gross rates in Fig. 1 frequently only level off even though
the intrinsic (specific) rates continue to diminish, this
allows us to hold onto the maximum power principle even in
senescence in many systems. Nevertheless, some ecosystems do
show declines, as indicated by the dotted line, which would
require a special explanation. Note that the Prigogine
principle is being interpreted (Salthe 1993) as a
characteristic of senescence (see also Zotin 1972, Kay 1984,
Jørgensen 2001a). The experiments that demonstrated it
(Prigogine and Wiame 1946) developed spontaneously into this
stable condition, which was then maintained by a continuing
low-level energy input. Of course, natural dissipative
systems do not get close to equilibrium at any stage, but
the point is that in senescence they are heading in that
direction. Environments are not nearly supportive enough to
allow systems to even approach a truly steady state before
being recycled.''

- http://www.ecologyandsociety.org/vol7/iss3/art3/main.html

My interpretation:

Prigogine>s principle hardly applies anywhere in practice.

The systems it is *most* applicable to are ones which are on
the verge of death - but it doesn>t apply very well to those
either.
--
__________
|im |yler http://timtyler.org/ tim@tt1lock.org Remove lock to reply.


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