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Thermodynamics, Information, and Life.

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General fitness, health and nutrition
Published
22 March 2004
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4 April 2004
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Jim Menegay
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  1. Probably more [censored] has been written about entropy than
    about any other scientific concept. Claude Shannon
    originally proposed to use the name "uncertainty" for his
    quantity-of-information concept, but John von Neumann
    suggested that the name "entropy" be used instead, first
    because there is a formal similarity in the mathematics, but
    "more important, no one knows what entropy really is, so in
    a debate you will always have the advantage."

    It turns out that there really is a relationship between
    Shannon entropy and thermodynamic entropy - at least in
    situations in which Shannon information is being transmitted
    through a noisy channel in which the noise is generated by a
    temperature T. But the suggested relationships among life,
    the second law, and "order" (whatever THAT is) are probably
    mistakes - mistakes that don't even attempt to express
    themselves as equations that balance the units of
    measurement.

    Still, it does seem that there is some kind of
    maximization or minimization going on in life - there
    ought to be some law-like description of that process.
    Since maximization principles in physics often ultimately
    reduce themselves to instances of the second law, it is
    perhaps understandable that so many intelligent people
    would be tempted to try to explain similar principles in
    biology as a result of the same law.

    A two part paper by Peter Corning and Steven Jay Kline
    offers a useful critique of these attempts. More
    importantly, the papers suggest an alternative metaphor upon
    which biologists can base their "laws" of maximization or
    minimization. That alternative metaphor is a field on the
    other side of the reductionist hierarchy from
    thermodynamics. Kline and Corning suggest that biologists
    should draw their inspiration not from physical chemistry,
    but from economics!

    I realize that few biologists have training in theoretical
    economics, except perhaps for some recent interest in game
    theory. That is, IMHO, unfortunate. For economics deals with
    the dynamics of complex systems of autonomous agents, each
    pursuing its own self interest, subject to externally
    imposed constraints. Furthermore, the nature of the
    interests, and of the constraints, are taken as being
    contingent - that is, not forced by the model. Surprisingly,
    given this apparent lack of law-like structure in the
    assumptions, there is a good deal of very law-like structure
    in the models that result, including many theorems that some
    quantity will, over time, tend to be maximized or minimized.
    For a bit of the flavor of these "laws" of economics, and
    for a discussion of how economists view the relationship of
    their laws to physical laws, I would recommend the Nobel
    Prize lecture by the second winner of the economics prize -
    Paul Samuelson. However, for those not trained in economics,
    I must warn that it will be very heavy going.

    To my mind, the foremost reason why biology should draw
    inspiration from economics, rather than physics, is that
    both are inexact sciences, subject to the contingencies both
    of history and of unpredictable local events. Though they
    both postulate agents that are seeking to maximize
    something, neither really believes that the agents are
    perfectly successful in their quest. Still, over the long
    term, and averaging over a large number of agents, the
    assumption of an optimizing agent makes sense. Of course,
    this optimizing is subject to constraint. In economics, the
    constraints come from technology; in biology, they come from
    biochemistry, biophysics, and the programs of development.

    There has been considerable discussion in this group of the
    ideas of Lotka, lately recast and championed by Kay and
    Schneider, that ecosystems evolve so as to maximize their
    utilization of free energy. By the ideas proposed here, this
    tendency, which certainly cannot be denied, should be seen
    not as a manifestation of the second law of thermodynamics.
    Instead, it should be seen as a manifestation of the same
    phenomenon that causes a free market economy to evolve so as
    to make the most efficient use of the technology available
    to it, and to drive the evolution of the technology in the
    most productive directions.

    The followers of Adam Smith have never been tempted to
    describe this direction of economic evolution as a
    manifestation of the laws of physics. Neither should the
    followers of Darwin be tempted to do so. IMHO.

    References:

    "Thermodynamics, information, and life revisited, parts 1 &
    2", Peter A. Corning; Stephen Jay Kline, Systems Research
    and Behavioral Science, 1998 (Available online via InfoTrac)

    "Maximum Principles in Analytical Economics", Paul
    Samuelson, Nobel lecture, 1970. nobel.sesamuelson
    lecture.html

  2. Jim Menegay <[email hidden]> wrote or quoted:

    Quoted message said:

    There has been considerable discussion in this group of
    the ideas of Lotka, lately recast and championed by Kay
    and Schneider, that ecosystems evolve so as to maximize
    their utilization of free energy. By the ideas proposed
    here, this tendency, which certainly cannot be denied,
    should be seen not as a manifestation of the second law of
    thermodynamics. Instead, it should be seen as a
    manifestation of the same phenomenon that causes a free
    market economy to evolve so as to make the most efficient
    use of the technology available to it, and to drive the
    evolution of the technology in the most productive
    directions.

    I don't believe the "biological thermodynamicists"
    (e.g. me) think the second law has much to do with it.

    [OK - Kay and Schneider's paper excepted :-)].

    What we are mostly proposing is *new* laws of
    thermodynamics.

    Kauffman - for example - makes this explicit - *entirely*
    new laws to deal with the dynamics of complex systems are
    required - and at their most fundamental level they will
    have a thermodynamic expression not covered by the existing
    thermodynamic laws.

    I agree completely - with the principle (though not the
    details): new laws of thermodynamics are on the books to
    deal with complex systems - and a significant task is to
    attempt to clearly elucidate them.

    Economic metaphors and thermodynamic metaphors are not
    mutually exclusive. You can look as many complex systems
    /either/ as though they are economies /or/ by considering
    their thermodynamics. Which description is better will
    depend on your system and why you are looking at it.

    I think many complex systems are *not* best regarded as
    economies. Turbulent fluid flow is one example.
    Crystallisation is another. I think economic metaphors are
    next-to-useless in those domains - whereas the thermodynamic
    descriptions are still highly applicable.

    So - I think the thermodyamic description is the more
    general one - and it underlies - and is responsible for -
    the dynamics of economies.

    However economic metaphors do have their virtues, through
    being a higher-level, more holistic description of the
    phenomena.

    A thermodynamic description of the stock exchange may be
    /technically/ correct - but is - perhaps - not necessarily
    very useful or practical, through being a description on too
    low a level.

    Quoted message said:

    The followers of Adam Smith have never been tempted to
    describe this direction of economic evolution as a
    manifestation of the laws of physics.

    ...though obviously it is just that ;-)

    Quoted message said:

    Neither should the followers of Darwin be tempted to do
    so. IMHO.

    Physics explains biology and economics but - perhaps - not
    in a very useful way.

    Anyway, we are not /really/ talking about physics. The
    second law of thermodynamics isn't /really/ a law and is
    isn't /really/ physics.

    Its a statement about statistical tendencies among systems
    with large numbers of components.

    It is not a "law" - since it can be broken - especially on
    small scales - and it has more to do with statistics than it
    does to do with physics.

    So it will be with the thermodyamic characterisations of
    complex systems: not /really/ laws - and more statistics
    than physics.
    --
    __________
    |im |yler timtyler.orgtimtyler.org [email hidden] Remove
    lock to reply.

  3. Hi Jim,

    I appreciate the view you described in this post (most of
    which I snipped for simplicity), however I think that you
    are either missing the point of the thermodynamic argument
    or you are dismissing it without a sufficiently explained
    justification.

    [snip]

    in article [email hidden], Jim Menegay at
    [email hidden] wrote on 3/22/04 9:30 AM:

    Quoted message said:

    There has been considerable discussion in this group of
    the ideas of Lotka, lately recast and championed by Kay
    and Schneider, that ecosystems evolve so as to maximize
    their utilization of free energy. By the ideas proposed
    here, this tendency, which certainly cannot be denied,
    should be seen not as a manifestation of the second law of
    thermodynamics. Instead, it should be seen as a
    manifestation of the same phenomenon that causes a free
    market economy to evolve so as to make the most efficient
    use of the technology available to it, and to drive the
    evolution of the technology in the most productive
    directions.

    The followers of Adam Smith have never been tempted to
    describe this direction of economic evolution as a
    manifestation of the laws of physics. Neither should the
    followers of Darwin be tempted to do so. IMHO.

    Interestingly, another Nobelist, Eugene Stanley (physicist),
    has been making quite a splash with the advent of the new
    discipline of econophysics. His argument for the
    thermodynamics of the economy is the same as the argument
    for the thermodynamics of biology (and evolution in
    particular). Although I appreciate the confusion you
    described over the term (and concept) "entropy", I don't see
    any reason to allow that confusion to get in the way of
    studying the context-specific implications of
    thermodynamics. There are, after all, no limitations to the
    concept of universality.

    Cheers,

    Guy

  4. Guy Hoelzer <[email hidden]> wrote in message news:<[email hidden]>...

    Quoted message said:

    Hi Jim,

    I appreciate the view you described in this post (most of
    which I snipped for simplicity), however I think that you
    are either missing the point of the thermodynamic argument
    or you are dismissing it without a sufficiently explained
    justification.

    [snip]

    in article [email hidden], Jim Menegay
    at [email hidden] wrote on 3/22/04 9:30 AM:

    Quoted message said:

    There has been considerable discussion in this group of
    the ideas of Lotka, lately recast and championed by Kay
    and Schneider, that ecosystems evolve so as to maximize
    their utilization of free energy. By the ideas proposed
    here, this tendency, which certainly cannot be denied,
    should be seen not as a manifestation of the second law
    of thermodynamics. Instead, it should be seen as a
    manifestation of the same phenomenon that causes a free
    market economy to evolve so as to make the most
    efficient use of the technology available to it, and to
    drive the evolution of the technology in the most
    productive directions.

    The followers of Adam Smith have never been tempted to
    describe this direction of economic evolution as a
    manifestation of the laws of physics. Neither should the
    followers of Darwin be tempted to do so. IMHO.

    Interestingly, another Nobelist, Eugene Stanley
    (physicist), has been making quite a splash with the
    advent of the new discipline of econophysics. His argument
    for the thermodynamics of the economy is the same as the
    argument for the thermodynamics of biology (and evolution
    in particular). Although I appreciate the confusion you
    described over the term (and concept) "entropy", I don't
    see any reason to allow that confusion to get in the way
    of studying the context-specific implications of
    thermodynamics. There are, after all, no limitations to
    the concept of universality.

    Cheers,

    Guy

    Thanks for the heads-up on Stanley and Econo-physics. I
    believe, after considerable searching, that you are wrong
    that he is a Nobelist, but he certainly does not appear to
    be a lightweight. I look forward to digging into his work
    and seeing what he says about "entropy". It seems similar,
    so far, to what I have read about what Norm Packard is or
    was doing at Los Alamos.

    A more detailed statement of why I want to construe
    "entropy" narrowly and to limit "thermodynamics" to systems
    with a "temperature" will appear in my reply to Tim.

  5. Tim Tyler <[email hidden]> wrote in message news:<[email hidden]>...

    Quoted message said:

    Jim Menegay <[email hidden]> wrote or quoted:

    Quoted message said:

    There has been considerable discussion in this group of
    the ideas of Lotka, lately recast and championed by Kay
    and Schneider, that ecosystems evolve so as to maximize
    their utilization of free energy. By the ideas proposed
    here, this tendency, which certainly cannot be denied,
    should be seen not as a manifestation of the second law
    of thermodynamics. Instead, it should be seen as a
    manifestation of the same phenomenon that causes a free
    market economy to evolve so as to make the most
    efficient use of the technology available to it, and to
    drive the evolution of the technology in the most
    productive directions.

    I don't believe the "biological thermodynamicists"
    (e.g. me) think the second law has much to do with it.

    [OK - Kay and Schneider's paper excepted :-)].

    If Lotka had first studied desert ecosystems, he might have
    proposed that they develop so as to maximize the utilization
    of water. If he had then moved on to potassium starved
    ecosystems, then to ecosystems deficient in soluble iron,
    and only then to rich, well watered ecosystems that get only
    12 hrs of sunlight per day, then he might have generalized
    that law to the "optimal utilization of scarce resources".
    And we would probably not be having this discussion.

    Quoted message said:


    What we are mostly proposing is *new* laws of
    thermodynamics.

    I have to quibble! What you guys are proposing are new laws
    of dynamics. These laws should properly be called
    "thermodynamic" laws only if you expect to test them using a
    thermometer! More on this below.

    Quoted message said:


    Kauffman - for example - makes this explicit - *entirely*
    new laws to deal with the dynamics of complex systems are
    required - and at their most fundamental level they will
    have a thermodynamic expression not covered by the
    existing thermodynamic laws.

    I agree completely - with the principle (though not the
    details): new laws of thermodynamics are on the books to
    deal with complex systems - and a significant task is to
    attempt to clearly elucidate them.

    Economic metaphors and thermodynamic metaphors are not
    mutually exclusive. You can look as many complex systems
    /either/ as though they are economies /or/ by considering
    their thermodynamics. Which description is better will
    depend on your system and why you are looking at it.

    I think many complex systems are *not* best regarded as
    economies.

    I only suggest economic models when there is inevitably
    teleology involved in the description of the low-level
    units, but the details of what those low-level units
    "desire" is laced with variation and contingency.

    Quoted message said:

    Turbulent fluid flow is one example. Crystallisation is
    another. I think economic metaphors are next-to-useless in
    those domains - whereas the thermodynamic descriptions are
    still highly applicable.

    Crystalization is adequately explained, AFAIK, by classical
    thermodynamics. No new laws are needed. Turbulence is
    unexplained, and the eventual explanation will have to make
    contact with thermodynamics. And, it will certainly be
    reductionistically based on statistical mechanics. But it
    won't be "thermodynamics", IMO. Again, more below.

    Quoted message said:


    So - I think the thermodyamic description is the more
    general one - and it underlies - and is responsible for -
    the dynamics of economies.

    However economic metaphors do have their virtues, through
    being a higher-level, more holistic description of the
    phenomena.

    A thermodynamic description of the stock exchange may be
    /technically/ correct - but is - perhaps - not necessarily
    very useful or practical, through being a description on
    too low a level.

    Quoted message said:

    The followers of Adam Smith have never been tempted to
    describe this direction of economic evolution as a
    manifestation of the laws of physics.

    ...though obviously it is just that ;-)

    Quoted message said:

    Neither should the followers of Darwin be tempted to do
    so. IMHO.

    Physics explains biology and economics but - perhaps - not
    in a very useful way.

    The extreme philosophy of reductionism espoused in the last
    few paragraphs just calls out for a response, even though it
    is off-topic. I will limit myself to pointing out that both
    economics and evolutionary theory can lay claim to being
    independent of physics - the theory of economics applies to
    any intelligent, aquisitive species - even if they inhabit a
    universe where the laws of physics are entirely different.
    Similarly, natural selection should also apply in other
    universes. In both cases, the theories reduce to axioms that
    are independent of physics. Neither reduces to physics. Our
    universe's physics only happens to be one way of
    implementing entities that satisfy the axioms.

    Quoted message said:


    Anyway, we are not /really/ talking about physics. The
    second law of thermodynamics isn't /really/ a law and is
    isn't /really/ physics.

    Its a statement about statistical tendencies among systems
    with large numbers of components.

    It is not a "law" - since it can be broken - especially on
    small scales - and it has more to do with statistics than
    it does to do with physics.

    So it will be with the thermodyamic characterisations of
    complex systems: not /really/ laws - and more statistics
    than physics.

    I am not sure whether our disagreement is purely
    terminological, or whether it is deeper. I would say that
    the second law of thermodynamics really is a law and that OF
    COURSE it is a law of physics. It cannot be broken in the
    situations where it applies - namely systems in which a
    "temperature" can be defined and which are close to thermal
    equilibrium. If you can't define a temperature, then you
    can't define entropy - the definition of entropy is based on
    a particular kind of heat capacity.

    Now it is true that the second law can be
    reductionistically explained by statistical mechanics,
    based on the work of Maxwell, Boltzmann, and Gibbs. And, it
    is also true that Einstein and others have explored the
    implications of that reduction at scales where a well-
    defined temperature no longer exists. They find
    fluctuations. Big deal. The second law is only
    approximately true when you try to apply it to situations
    where it is no longer applicable. It is still as much a law
    as Newton's gravitation, or, for that matter, quantum
    mechanics or Einstein's gravitation, both of which are
    expected to fail at the Planck length and/or Planck mass.

    It is worth looking at the reduction of the second law to
    statistical mechanics in more detail. The first law -
    conservation of energy - is a required assumption. From the
    first law, we can derive Liouville's theorem - that
    microscopic phase space volume is conserved as any ensemble
    moves through phase space. But the log of the ratio between
    microscopic phase space volume and macroscopic phase space
    volume (i.e. the entropy, in Shannon's sense) is not a
    constant. With probability one, entropy is non-decreasing.

    So, you want to claim that your favorite new macro-level
    "law" is an extension of the second law of thermodynamics?
    You want to call some new non-decreasing quantity a new kind
    of "entropy"? I will bless this enterprise, only if you
    satisfy four requirements.

    1. You need an analogue of energy, that is conserved
    and supports a Liouville theorem. Energy itself
    would do nicely.
    2. You need an analogue of temperature, which is itself
    proportional to the "kinetic" portion of your energy
    analogue. There must be a fairly rapid equipartition of
    the kinetic "energy" so that there is a rapid approach to
    thermal equilibrium.
    3. It must be the case that "entropy" times "temperature"
    has the dimensions of "energy".
    4. Your "entropy" is the log of a ratio between micro and
    macro phase space volumes.

    Or you can proceed without my blessing. ;-( However ... I
    would prefer that you announce your results as a new law of
    nature, rather than further overloading the term "entropy"
    and claiming to have merely extended the second law. It will
    create less confusion.

    Which is not to say that second law extensions or second law
    analogues that meet my criteria are impossible. I am myself
    working on an idea that has the mutation rate in the role of
    temperature and fitness in the role of enthalpy. Will it pan
    out? Who knows! It may well pan out, but without sustaining
    the analogy with chemical thermodynamics. If that turns out
    to be the case, then I hope that I will refrain from
    increasing the confusion by claiming that my measure of gene
    information really IS entropy, and that its increase over
    time is an application of the second law of thermodynamics.

  6. Long post alert :-|

    Jim Menegay <[email hidden]> wrote or quoted:

    Quoted message said:
    Tim Tyler said:

    Jim Menegay <[email hidden]> wrote or quoted:

    Quoted message said:
    Quoted message said:
    Quoted message said:

    There has been considerable discussion in this group
    of the ideas of Lotka, lately recast and championed by
    Kay and Schneider, that ecosystems evolve so as to
    maximize their utilization of free energy. By the
    ideas proposed here, this tendency, which certainly
    cannot be denied, should be seen not as a
    manifestation of the second law of thermodynamics.
    Instead, it should be seen as a manifestation of the
    same phenomenon that causes a free market economy to
    evolve so as to make the most efficient use of the
    technology available to it, and to drive the evolution
    of the technology in the most productive directions.

    I don't believe the "biological thermodynamicists"
    (e.g. me) think the second law has much to do with it.

    [OK - Kay and Schneider's paper excepted :-)].

    If Lotka had first studied desert ecosystems, he might
    have proposed that they develop so as to maximize the
    utilization of water. If he had then moved on to potassium
    starved ecosystems, then to ecosystems deficient in
    soluble iron, and only then to rich, well watered
    ecosystems that get only 12 hrs of sunlight per day, then
    he might have generalized that law to the "optimal
    utilization of scarce resources". And we would probably
    not be having this discussion.

    A hypothetical I feel I can pass over.

    Quoted message said:
    Quoted message said:

    What we are mostly proposing is *new* laws of
    thermodynamics.

    I have to quibble! What you guys are proposing are new
    laws of dynamics. These laws should properly be called
    "thermodynamic" laws only if you expect to test them using
    a thermometer! More on this below.

    These are laws of thermodynamics as much as the second law
    is. They involve "heat" - but they /also/ involve "order".

    If you also want to rename the second law - since that
    doesn't deal solely with temperature either - then that's
    fine with me - but I think this is a bit of a different
    discussion.

    It's a discussion about the *naming* of things - and it's
    not really an argument with me, it's an argument with the
    scientific community.

    Quoted message said:
    Quoted message said:

    Kauffman - for example - makes this explicit -
    *entirely* new laws to deal with the dynamics of complex
    systems are required - and at their most fundamental
    level they will have a thermodynamic expression not
    covered by the existing thermodynamic laws.

    I agree completely - with the principle (though not the
    details): new laws of thermodynamics are on the books to
    deal with complex systems - and a significant task is to
    attempt to clearly elucidate them.

    Economic metaphors and thermodynamic metaphors are not
    mutually exclusive. You can look as many complex systems
    /either/ as though they are economies /or/ by
    considering their thermodynamics. Which description is
    better will depend on your system and why you are
    looking at it.

    I think many complex systems are *not* best regarded as
    economies.

    I only suggest economic models when there is inevitably
    teleology involved in the description of the low-level
    units, but the details of what those low-level units
    "desire" is laced with variation and contingency.

    There it makes sense.

    What about the case of a single individual - the man on the
    desert island?

    It seems like he as still doing some dissipation of low-
    entropy sources and acting as a dissipative structure -
    but it is not so easy for me to see him as a player in
    an economy.

    We could see him as the product of a previous economy,
    perhaps - but economies can make all sorts of stuff - and
    we need more information to say anything about how the
    man behaves.

    Quoted message said:
    Quoted message said:

    Turbulent fluid flow is one example. Crystallisation is
    another. I think economic metaphors are next-to-useless
    in those domains - whereas the thermodynamic
    descriptions are still highly applicable.

    Crystalization is adequately explained, AFAIK, by
    classical thermodynamics. No new laws are needed. [...]

    Crystalization isn't explained by thermodynamics.

    It's explained by the laws of physics.

    The results are consistent with existing "laws" of
    thermodynamics.

    Of course this is also true of biological systems.

    Imagine for a moment that the second law had not yet
    been created.

    Crystalization is consistent with the Zeroth and First laws
    of thermodynamics - what need is there for a "second law"?

    The answer is that the second law provides more information
    about the behaviour of the system. It doesn't change the
    temporal evolution of the system, but rather represents an
    observation about its behaviour.

    In this case, one area which the existing laws don't address
    is the question of what happens to the entropy of a super-
    saturated solution when you introduce a self-organising
    system into it - in the form of a crystal seed.

    The answer is that often the rate of entropy rise will
    increase substantially.

    Laws 0-2 don't have anything to say about the subject.
    That's one of the reasons more rules are needed.

    Self organising systems are an important part of the world -
    and are the subject of fairly general thermodynamic laws.

    Quoted message said:
    Quoted message said:

    So - I think the thermodyamic description is the more
    general one - and it underlies - and is responsible for
    - the dynamics of economies.

    However economic metaphors do have their virtues,
    through being a higher-level, more holistic description
    of the phenomena.

    A thermodynamic description of the stock exchange may be
    /technically/ correct - but is - perhaps - not
    necessarily very useful or practical, through being a
    description on too low a level.

    Quoted message said:

    The followers of Adam Smith have never been tempted to
    describe this direction of economic evolution as a
    manifestation of the laws of physics.

    ...though obviously it is just that ;-)

    Quoted message said:

    Neither should the followers of Darwin be tempted to
    do so. IMHO.

    Physics explains biology and economics but - perhaps -
    not in a very useful way.

    The extreme philosophy of reductionism espoused in the
    last few paragraphs just calls out for a response, even
    though it is off-topic. I will limit myself to pointing
    out that both economics and evolutionary theory can lay
    claim to being independent of physics - the theory of
    economics applies to any intelligent, aquisitive species -
    even if they inhabit a universe where the laws of physics
    are entirely different. Similarly, natural selection
    should also apply in other universes. In both cases, the
    theories reduce to axioms that are independent of physics.
    Neither reduces to physics. Our universe's physics only
    happens to be one way of implementing entities that
    satisfy the axioms.

    I'm rather bemused about where this one came from ;-)

    Perhaps you would rather I had said physics, mathematics and
    logic explain biology and economics.

    If it helps you can pretend I said that.

    Don't try and tell me physics can be left out of the
    equation, though.

    It is a trivial matter to imagine physical universes where
    the laws of biology and economics fail to function - or work
    totally differently.

    Quoted message said:
    Quoted message said:

    Anyway, we are not /really/ talking about physics. The
    second law of thermodynamics isn't /really/ a law and is
    isn't /really/ physics.

    Its a statement about statistical tendencies among
    systems with large numbers of components.

    It is not a "law" - since it can be broken - especially
    on small scales - and it has more to do with statistics
    than it does to do with physics.

    So it will be with the thermodyamic characterisations of
    complex systems: not /really/ laws - and more statistics
    than physics.

    I am not sure whether our disagreement is purely
    terminological, or whether it is deeper. I would say that
    the second law of thermodynamics really is a law and that
    OF COURSE it is a law of physics. It cannot be broken in
    the situations where it applies - namely systems in which
    a "temperature" can be defined and which are close to
    thermal equilibrium. If you can't define a temperature,
    then you can't define entropy - the definition of entropy
    is based on a particular kind of heat capacity.

    The second law really can be broken - on any scale you care
    to mention.

    *If* you accept that laws of nature are rules that permit no
    exceptions, then statements to the effect that "entropy
    always stays the same or increases" are not laws because
    they are seen to be broken.

    Quoted message said:

    Now it is true that the second law can be
    reductionistically explained by statistical mechanics,
    based on the work of Maxwell, Boltzmann, and Gibbs. And,
    it is also true that Einstein and others have explored the
    implications of that reduction at scales where a well-
    defined temperature no longer exists. They find
    fluctuations. Big deal. The second law is only
    approximately true when you try to apply it to situations
    where it is no longer applicable. It is still as much a
    law as Newton's gravitation, or, for that matter, quantum
    mechanics or Einstein's gravitation, both of which are
    expected to fail at the Planck length and/or Planck mass.

    You are arguing that laws of nature can be broken by nature.

    I don't think this is the conventional view.

    More orthodox would be the view the Newtonian mechanics,
    relativity and quantum physics will turn out /not/ to be the
    laws of nature, but mere approximations thereof.

    Quoted message said:

    So, you want to claim that your favorite new macro-level
    "law" is an extension of the second law of thermodynamics?

    No, I don't. I don't think I ever said that. Indeed in my
    last post I said just the opposite.

    Not a tweak of the second law.

    A whole new set of rules to describe the behaviour of
    complex systems in thermodynamic terms.

    Quoted message said:

    You want to call some new non-decreasing quantity a new
    kind of "entropy"?

    *Mainly* I want to characterise existing thermodynamic
    behaviour of complex systems in terms of the existing -
    perfectly conventional - sort of entropy.

    *Mainly* I want to say how complex, self-organising systems
    are characterised by their effect on making entropy (the
    usual sort) increase more rapidly.

    However...

    I *do* also see evolution as having a (mostly) progressive
    character - and also seek to lawfully describe how the
    accumulation of technology by ecosystems helps them more
    rapidly exploit thier resources.

    *If* you liked, you could indeed see this "state of
    technological" development of a system as an *analogous*
    quanity to entropy.

    It would also be subject to continuous increase. Local
    decreases would be allowed - e.g. as particular species
    with a significant invention were destroyed; or as planets
    were wiped out in collisions - but overall progress would
    be ensured.

    However I never referred to this quanity as remotely
    "entropy like" until after you did (above).

    When I have said entropy, on previous occasions I have
    always meant it in the completely conventional sense.

    Quoted message said:

    I will bless this enterprise, only if you satisfy four
    requirements.

    1. You need an analogue of energy, that is conserved and
    supports a Liouville theorem. Energy itself would do
    nicely.
    2. You need an analogue of temperature, which is itself
    proportional to the "kinetic" portion of your energy
    analogue. There must be a fairly rapid equipartition of
    the kinetic "energy" so that there is a rapid approach
    to thermal equilibrium.
    3. It must be the case that "entropy" times "temperature"
    has the dimensions of "energy".
    4. Your "entropy" is the log of a ratio between micro and
    macro phase space volumes.

    Or you can proceed without my blessing. ;-(

    Your requirements are too taxing for me.

    This may be straining the analogy you seem to think I am
    proposing very greatly.

    The connection I see between the conventional entropy and my
    "state of development of an ecosystem" are that both are
    (statistically speaking) increasing quantities.

    However I don't see all the requirements above as being very
    relevant. I'm not suggesting it is "entropy writ large" or
    "entropy for complex systems". It might be a different sort
    of thing with its own laws, and an analogy with entropy
    might be quite inappropriate.

    I still see the notion as fundamentally thermodynamic
    - since it deals with the rate at which ecosystems can
    increase the entropy of their environments changes
    with time.

    However I am *not* calling them thermodynamic because of the
    existence of some sort of new-fangled "meta-entropy" that
    also happens to be increasing most-of-the-time.

    I am calling them thermodynamic because they are a statement
    about common or garden entropy. The second law of
    thermodynamics is /also/ a statement about what this common
    or garden entropy does - and so a similar name seems
    appropriate.

    Quoted message said:

    I would prefer that you announce your results as a new law
    of nature, rather than further overloading the term
    "entropy" and claiming to have merely extended the second
    law. It will create less confusion.

    I agree.

    This whole analogy between the state of development of
    ecosystems and entropy is your suggestion as far as I am
    concerned.

    I had never even considered the analogy between my "state
    of technological development" - or - "ability to rapidly
    exhaust resources" notions and entropy until you
    mentioned it.

    As for "Extending the second law" - that isn't the
    idea at all.

    New laws of thermodynamics to characteries the behaviour of
    complex systems.

    No messing with the existing laws ;-)

    The title of Kay and Schnier's paper is unfortunate - in
    that it might give this impression.

    Quoted message said:

    Which is not to say that second law extensions or second
    law analogues that meet my criteria are impossible. I am
    myself working on an idea that has the mutation rate in
    the role of temperature and fitness in the role of
    enthalpy. Will it pan out? Who knows! It may well pan out,
    but without sustaining the analogy with chemical
    thermodynamics. If that turns out to be the case, then I
    hope that I will refrain from increasing the confusion by
    claiming that my measure of gene information really IS
    entropy, and that its increase over time is an application
    of the second law of thermodynamics.

    This is like a straw man to me. It seems to me to be a great
    distance from anything I've thought or written.

    Re: your idea of fitness increasing. You haven't explained
    this - but - IMO - it would translate into organisms having
    more and more surviving offspring as time passed.

    I believe you need a continuously-expanding - environment to
    pull that trick off for very long ;-)
    --
    __________
    |im |yler timtyler.orgtimtyler.org [email hidden] Remove
    lock to reply.

  7. in article [email hidden], Jim Menegay at
    [email hidden] wrote on 3/23/04 4:44 PM:

    Quoted message said:

    Thanks for the heads-up on Stanley and Econo-physics. I
    believe, after considerable searching, that you are wrong
    that he is a Nobelist, but he certainly does not appear to
    be a lightweight.

    I may be wrong about his Nobel-ness, but you are right that
    he could not possibly be considered a lightweight. I though
    he was one of three theoretical physicists who won the Nobel
    prize for development of renormalization group analysis. If
    you are not familiar with this method you might find it very
    interesting. The claim for the method, which has been deemed
    valid by the theoretical physics community, is that it can
    prove with certainty that all systems with a particular,
    small set of rules will have certain characteristic
    tendencies regardless of the other details of the systems.
    In other words, it claims to be a proof of inductive
    validity, which was previously thought to be impossible
    based in part on Popper's philosophy.

    Quoted message said:

    I look forward to digging into his work and seeing what
    he says about "entropy". It seems similar, so far, to
    what I have read about what Norm Packard is or was doing
    at Los Alamos.

    As I understand it, Stanley and Packard (not to mention
    other notable theoreticians like Stuart Kauffman and Doyne
    Farmer) have been applying thermodynamics to economics
    aiming to solve similar problems, but they have been
    developing somewhat different approaches.

    Quoted message said:

    A more detailed statement of why I want to construe
    "entropy" narrowly and to limit "thermodynamics" to
    systems with a "temperature" will appear in my reply to
    Tim.

    I look forward to reading it.

    Cheers,

    Guy

  8. in article [email hidden], Jim Menegay at
    [email hidden] wrote on 3/23/04 10:43 PM:

    Quoted message said:

    Tim Tyler <[email hidden]> wrote in message
    news:<[email hidden]>...

    Quoted message said:

    Jim Menegay <[email hidden]> wrote or quoted:

    Quoted message said:

    There has been considerable discussion in this group of
    the ideas of Lotka, lately recast and championed by Kay
    and Schneider, that ecosystems evolve so as to maximize
    their utilization of free energy. By the ideas proposed
    here, this tendency, which certainly cannot be denied,
    should be seen not as a manifestation of the second law
    of thermodynamics. Instead, it should be seen as a
    manifestation of the same phenomenon that causes a free
    market economy to evolve so as to make the most
    efficient use of the technology available to it, and to
    drive the evolution of the technology in the most
    productive directions.

    I don't believe the "biological thermodynamicists"
    (e.g. me) think the second law has much to do with it.

    [OK - Kay and Schneider's paper excepted :-)].

    If Lotka had first studied desert ecosystems, he might
    have proposed that they develop so as to maximize the
    utilization of water. If he had then moved on to potassium
    starved ecosystems, then to ecosystems deficient in
    soluble iron, and only then to rich, well watered
    ecosystems that get only 12 hrs of sunlight per day, then
    he might have generalized that law to the "optimal
    utilization of scarce resources". And we would probably
    not be having this discussion.

    It has always seemed to me that Lotka worked hard to break
    free of local details in his theorizing. You might be
    selling him short in this expectation. I can tell you that
    Lotka's work was considered fully applicable to desert
    ecosystems by the Ecology faculty at the University of
    Arizona, where I did my dissertation work.

    Quoted message said:
    Quoted message said:

    What we are mostly proposing is *new* laws of
    thermodynamics.

    I have to quibble! What you guys are proposing are new
    laws of dynamics. These laws should properly be called
    "thermodynamic" laws only if you expect to test them using
    a thermometer! More on this below.

    This is a pretty blunt statement. I agree that it will be
    important to take the temperatures of dynamical systems, and
    to study how they change as their temperatures change, but
    this shouldn't define the limits of empirical research on
    complex systems any more than taking temperatures has
    limited previous research in thermodynamics.

    Quoted message said:
    Quoted message said:

    Kauffman - for example - makes this explicit - *entirely*
    new laws to deal with the dynamics of complex systems are
    required - and at their most fundamental level they will
    have a thermodynamic expression not covered by the
    existing thermodynamic laws.

    I agree completely - with the principle (though not the
    details): new laws of thermodynamics are on the books to
    deal with complex systems - and a significant task is to
    attempt to clearly elucidate them.

    Economic metaphors and thermodynamic metaphors are not
    mutually exclusive. You can look as many complex systems
    /either/ as though they are economies /or/ by considering
    their thermodynamics. Which description is better will
    depend on your system and why you are looking at it.

    I think many complex systems are *not* best regarded as
    economies.

    I only suggest economic models when there is inevitably
    teleology involved in the description of the low-level
    units, but the details of what those low-level units
    "desire" is laced with variation and contingency.

    This all seems logical to me. Very interesting. IMHO we
    don't yet know of any simple (not dynamical or composed of
    interacting parts) "low-level units." We don't yet know, for
    example, whether quarks or photons are decomposable. Perhaps
    the requirements for teleology of the parts go beyond
    complexity. Do you have an objective way of assessing the
    teleology of parts, or a theoretical basis for the minimal
    aspects of a thing that would imbue it with teleology?

    Quoted message said:
    Quoted message said:

    Turbulent fluid flow is one example. Crystallisation is
    another. I think economic metaphors are next-to-useless
    in those domains - whereas the thermodynamic descriptions
    are still highly applicable.

    Crystalization is adequately explained, AFAIK, by
    classical thermodynamics. No new laws are needed.

    What is it in classical thermodynamics that predicts
    crystallization will generically result in geometric
    patterns? And can classical thermodynamics predict which
    pattern will be formed based on extensive knowledge of the
    qualities of the parts? As I understand classical
    thermodynamics, it only guides us in interpreting the self-
    organized patterns that result from crystallization. I would
    argue that a key aspect of the "new thermodynamics" is that
    it extends the classical framework to include a deeper
    understanding of pattern formation, including predictions
    about generic tendencies are not contingent upon
    externalities (note my comments on renormalization group
    analysis in my previous post).

    Quoted message said:

    Turbulence is unexplained, and the eventual explanation
    will have to make contact with thermodynamics. And, it
    will certainly be reductionistically based on statistical
    mechanics. But it won't be "thermodynamics", IMO. Again,
    more below.

    I would expect that statistical mechanics will be an basis
    for mean field models predicting turbulent patterns in
    particular contexts, but it's reductionistism will prevent
    this approach from effectively characterizing the generic
    (non-contingent, inductively valid) features of turbulence.

    Quoted message said:
    Quoted message said:

    So - I think the thermodyamic description is the more
    general one - and it underlies - and is responsible for -
    the dynamics of economies.

    However economic metaphors do have their virtues, through
    being a higher-level, more holistic description of the
    phenomena.

    A thermodynamic description of the stock exchange may be
    /technically/ correct - but is - perhaps - not
    necessarily very useful or practical, through being a
    description on too low a level.

    Quoted message said:

    The followers of Adam Smith have never been tempted to
    describe this direction of economic evolution as a
    manifestation of the laws of physics.

    ...though obviously it is just that ;-)

    Quoted message said:

    Neither should the followers of Darwin be tempted to do
    so. IMHO.

    Physics explains biology and economics but - perhaps -
    not in a very useful way.

    The extreme philosophy of reductionism espoused in the
    last few paragraphs just calls out for a response, even
    though it is off-topic. I will limit myself to pointing
    out that both economics and evolutionary theory can lay
    claim to being independent of physics - the theory of
    economics applies to any intelligent, aquisitive species -
    even if they inhabit a universe where the laws of physics
    are entirely different. Similarly, natural selection
    should also apply in other universes. In both cases, the
    theories reduce to axioms that are independent of physics.
    Neither reduces to physics. Our universe's physics only
    happens to be one way of implementing entities that
    satisfy the axioms.

    How can you know this? I don't think it is even a question
    you can address until economic or evolutionary theory find
    their links to physical theory in this universe. Then you
    could try to change the assumed physical laws and look for
    changes in the emergent economies or life.

    The other point I want to make here is that while the
    origins of theoretical economics and evolution were not
    based on physical theory, it does not mean that manifested
    economics and biology are not physical or controlled by
    physical laws. One of the primary goals of extending
    thermodynamics theory is IMHO to build a conduit for linking
    these historically unlinked bodies of theory. Thermodynamics
    is, after all, the branch of theoretical physics dealing
    explicitly with macroscopic phenomena.

    Quoted message said:
    Quoted message said:

    Anyway, we are not /really/ talking about physics. The
    second law of thermodynamics isn't /really/ a law and is
    isn't /really/ physics.

    Its a statement about statistical tendencies among
    systems with large numbers of components.

    It is not a "law" - since it can be broken - especially
    on small scales - and it has more to do with statistics
    than it does to do with physics.

    So it will be with the thermodyamic characterisations of
    complex systems: not /really/ laws - and more statistics
    than physics.

    I am not sure whether our disagreement is purely
    terminological, or whether it is deeper. I would say that
    the second law of thermodynamics really is a law and that
    OF COURSE it is a law of physics.

    I agree in principle, but we may disagree on technicalities.
    I would say that there is a physical law (Tim and some
    others would argue more than one) that has been articulated
    as the second law of thermodynamics. This view allows for a
    degree of mismatch between the nature of real physics and
    our articulation of the law, which is consistent with the
    tortured history of alternative articulations of the law,
    including the definition of entropy.

    Quoted message said:

    It cannot be broken in the situations where it applies -
    namely systems in which a "temperature" can be defined and
    which are close to thermal equilibrium. If you can't
    define a temperature, then you can't define entropy
    - the definition of entropy is based on a particular kind
    of heat capacity.

    This is certainly the biggest challenge right now for
    theoretical physicists working on the thermodynamics of far-from-
    equilibrium systems. I see this as enormously important,
    because real physical systems (e.g., economics and biology)
    may be universally far from equilibrium.

    Quoted message said:

    Now it is true that the second law can be
    reductionistically explained by statistical mechanics,
    based on the work of Maxwell, Boltzmann, and Gibbs.

    I will be rather picky here and take issue with your use of
    the word "explained," which implies a sort of mechanical
    truism in the reductionistic paradigm. I would say that
    these folks did a great job of reductionistically modeling
    the effects of the second law, but that their models are
    ultimately insufficient as explanations because they fail to
    consider the top down effects that drive self-organization.

    Quoted message said:

    And, it is also true that Einstein and others have
    explored the implications of that reduction at scales
    where a well-defined temperature no longer exists. They
    find fluctuations. Big deal. The second law is only
    approximately true when you try to apply it to situations
    where it is no longer applicable. It is still as much a
    law as Newton's gravitation, or, for that matter, quantum
    mechanics or Einstein's gravitation, both of which are
    expected to fail at the Planck length and/or Planck mass.

    If laws are not meant to reflect universalities, then I
    suggest that they get a different term indicating that they
    are contingent. I would also suggest that the search for non-
    contingent universalities (at least for our universe) is
    very important, and that I suspect we are on track with our
    current understanding of thermodynamics. This is why I am
    keen on continuing to refine the way we articulate the
    second law.

    Quoted message said:

    It is worth looking at the reduction of the second law to
    statistical mechanics in more detail. The first law -
    conservation of energy - is a required assumption. From
    the first law, we can derive Liouville's theorem - that
    microscopic phase space volume is conserved as any
    ensemble moves through phase space. But the log of the
    ratio between microscopic phase space volume and
    macroscopic phase space volume (i.e. the entropy, in
    Shannon's sense) is not a constant. With probability one,
    entropy is non-decreasing.

    This result is entirely consistent with the proposed
    expansion of the second law to say something like all
    macroscopic systems emerge because they serve to increase
    the rate of universal entropy increase.

    Quoted message said:

    So, you want to claim that your favorite new macro-level
    "law" is an extension of the second law of thermodynamics?

    Are you implying that classical thermodynamics is not
    fundamentally about macroscopic phenomena?

    Quoted message said:

    You want to call some new non-decreasing quantity a new
    kind of "entropy"?

    I, for one, am not proposing any new kind of entropy. This
    is a sticky issue, and I see no need to get into that
    quagmire in order to address these issues.

    Quoted message said:

    I will bless this enterprise, only if you satisfy four
    requirements.

    1. You need an analogue of energy, that is conserved and
    supports a Liouville theorem. Energy itself would do
    nicely.

    I am sure you are aware of the ongoing debate among
    physicists about the distinction, or lack thereof, to be
    made between energy and information. This debate often, but
    not always, centers around the leap Shannon made with use of
    the term entropy.

    Quoted message said:

    2. You need an analogue of temperature, which is itself
    proportional to the "kinetic" portion of your energy
    analogue. There must be a fairly rapid equipartition of
    the kinetic "energy" so that there is a rapid approach
    to thermal equilibrium.
    3. It must be the case that "entropy" times "temperature"
    has the dimensions of "energy".
    4. Your "entropy" is the log of a ratio between micro and
    macro phase space volumes.

    I don't feel comfortable judging the usefulness of your
    requirements, but they strike me as possibly requiring
    maintenance of artificial aspects of past models, rather
    than more fundamental theoretical considerations.

    Quoted message said:

    Or you can proceed without my blessing. ;-( However ... I
    would prefer that you announce your results as a new law
    of nature, rather than further overloading the term
    "entropy" and claiming to have merely extended the second
    law. It will create less confusion.

    I have had plenty of discussions on this issue, and I have
    an issue with your position (with which I think Tim agrees)
    that nobody has answered to my satisfaction. What would be
    the point of articulating a fourth law that completely
    implies the second law? It would be like having a law
    against murder and a second law against murder with a knife.

    Quoted message said:

    Which is not to say that second law extensions or second
    law analogues that meet my criteria are impossible. I am
    myself working on an idea that has the mutation rate in
    the role of temperature and fitness in the role of
    enthalpy.

    I will have to think of the fitness=enthalpy part, but the
    mutation rate as temperature has occurred to me and at least
    a few others I know of.

    Quoted message said:

    Will it pan out? Who knows! It may well pan out, but
    without sustaining the analogy with chemical
    thermodynamics. If that turns out to be the case, then I
    hope that I will refrain from increasing the confusion by
    claiming that my measure of gene information really IS
    entropy, and that its increase over time is an application
    of the second law of thermodynamics.

    Fair enough.

    Regards,

    Guy

  9. Tim Tyler <[email hidden]> wrote in message news:<[email hidden]>...

    It IS getting long. In an attempt to wrap this one up, let
    me just say that I wasn't trying to attack your ideas on
    thermo, but rather some rather wooly ones that are "out
    there" - particularly those of Brooks and Wiley.

    Responses to just a couple more points:

    Quoted message said:

    [snip] Imagine for a moment that the second law had not
    yet been created.

    Crystalization is consistent with the Zeroth and First
    laws of thermodynamics - what need is there for a
    "second law"?

    The answer is that the second law provides more
    information about the behaviour of the system. It doesn't
    change the temporal evolution of the system, but rather
    represents an observation about its behaviour.

    I have to disagree. Without the second law, there would be
    no reason not to expect a crystal to dissolve (absorbing
    heat) in a supersaturated solution. No reason not to expect
    a crystal to grow in an unsaturated solution. It is the
    second law that provides an "arrow" to the temporal
    evolution of the system.

    Without the second law, there would be no "tendency to seek
    the state of lowest energy". After all, following the first
    law, energy is conserved, so all states have the same
    energy. The zeroth law doesn't provide an arrow either, for
    anything except temperature.

    But you HAVE TO have already known this. So, I must be
    misinterpreting what you wrote. But how?

    Quoted message said:

    [snip] Re: your idea of fitness increasing. You haven't
    explained this - but - IMO - it would translate into
    organisms having more and more surviving offspring as
    time passed.

    I believe you need a continuously-expanding - environment
    to pull that trick off for very long ;-)

    Nope. Just a continuously deteriorating environment.
    Fisher's "fundamental theorem" says that the genetical
    component of fitness is non-decreasing. But he avoids having
    continuously increasing populations by claiming that the
    environment is continually deteriorating. Only recently have
    theorists realized that Fisher was including the average
    fitness of competing conspecifics as a component of the
    environment. So, we have a "Red Queen" race - fitness
    continually increases, but number of offspring do not.

  10. Tim Tyler <[email hidden]> wrote in message news:<[email hidden]>...

    Quoted message said:

    [snip]

    Quoted message said:

    I am myself working on an idea that has the mutation
    rate in the role of temperature and fitness in the role
    of enthalpy. [snip]

    Re: your idea of fitness increasing. [snip]

    Not my idea. Darwin's and Fisher's. My idea is that fitness
    corresponds to enthalpy, not entropy. I defend Fisher in my
    other response.

  11. Guy Hoelzer <[email hidden]> wrote in message news:<[email hidden]>...

    Quoted message said:

    in article [email hidden], Jim Menegay
    at [email hidden] wrote on 3/23/04 4:44 PM:

    Quoted message said:

    Thanks for the heads-up on Stanley and Econo-physics. I
    believe, after considerable searching, that you are
    wrong that he is a Nobelist, but he certainly does not
    appear to be a lightweight.

    I may be wrong about his Nobel-ness, but you are right
    that he could not possibly be considered a lightweight. I
    though he was one of three theoretical physicists who won
    the Nobel prize for development of renormalization group
    analysis.

    I believe, after more searching, that Kenneth Wilson is the
    only person to receive a Nobel prize based on the
    renormalization group.

    Quoted message said:

    If you are not familiar with this method you might find it
    very interesting.

    I'm familiar with Wilson's work from Paul Davies' book, "The
    New Physics".

    Quoted message said:

    The claim for the method, which has been deemed valid by
    the theoretical physics community, is that it can prove
    with certainty that all systems with a particular, small
    set of rules will have certain characteristic tendencies
    regardless of the other details of the systems. In other
    words, it claims to be a proof of inductive validity,
    which was previously thought to be impossible based in
    part on Popper's philosophy.

    But this is new to me. References would be appreciated.

    Gee, those physicists are busy and clever people. Solving
    problems in economics, theology, and now philosophy.
    Someday, maybe, they will crack turbulence. And they have so
    much insight into the issues in other fields! The one
    econophysics paper I have read so far (It was listed on the
    WEB site as paper-of-the-month.) was more of a critique of
    classical economics than a positive contribution. It
    expressed horror that the supply and demand curves that the
    author had encountered in textbooks were drawn without error
    bars. Now THAT is a helpful suggestion!

    I begin to understand the reaction of psychologists,
    anthropologists, and sociologists when Sociobiology was
    published.

  12. Guy Hoelzer <[email hidden]> wrote in message news:<[email hidden]>...

    Quoted message said:

    in article [email hidden], Jim Menegay
    at [email hidden] wrote on 3/23/04 10:43 PM:

    Quoted message said:

    Tim Tyler <[email hidden]> wrote in message
    news:<[email hidden]>...

    Quoted message said:

    Jim Menegay <[email hidden]> wrote or quoted:
    [snip much throughout] [TT] What we are mostly
    proposing is *new* laws of thermodynamics.

    I have to quibble! What you guys are proposing are new
    laws of dynamics. These laws should properly be called
    "thermodynamic" laws only if you expect to test them
    using a thermometer! More on this below.

    This is a pretty blunt statement. I agree that it will be
    important to take the temperatures of dynamical systems,

    Agree with who? Not me. What I said is that it is essential
    to take the temperature of a "thermodynamic" system. You can
    leave thermometer at home if you are studying a generic
    dynamical system, for all I care.

    Quoted message said:

    and to study how they change as their temperatures change,
    but this shouldn't define the limits of empirical research
    on complex systems [I agree] any more than taking
    temperatures has limited previous research in
    thermodynamics.

    But I would claim that taking temperatures DELIMITS
    thermodynamics, based as it is on three key concepts -
    temperature, heat, and entropy. I'm pretty sure heat and
    entropy cannot even be defined at the macro level without
    invoking temperature. [snip]

    Quoted message said:
    Quoted message said:

    I only suggest economic models when there is inevitably
    teleology involved in the description of the low-level
    units, but the details of what those low-level units
    "desire" is laced with variation and contingency.

    This all seems logical to me. Very interesting. IMHO we
    don't yet know of any simple (not dynamical or composed of
    interacting parts) "low-level units." We don't yet know,
    for example, whether quarks or photons are decomposable.
    Perhaps the requirements for teleology of the parts go
    beyond complexity. Do you have an objective way of
    assessing the teleology of parts, or a theoretical basis
    for the minimal aspects of a thing that would imbue it
    with teleology?

    Talking about "decomposability" misses the point, IMO.
    The real question is whether we (as scientists and
    theorists) want to decompose beyond a particular point.
    The same applies to whether to use teleology in the
    description of the part.

    Example: John likes popcorn. For that reason, he buys it. An
    economist needs a little more information than this - for
    example, how much is he willing to pay? But the economist
    doesn't need and doesn't want a reductionist explanation of
    John's desires, nor does the economist feel that progress
    has been made if the reductionist explanation removes the
    teleology. The economist has all the information he needs
    about popcorn, and is ready to move on to other commodities
    such as poppyseed rolls, pornography, and post-hole diggers.
    A reductionist explanation would not economize on the data
    required to construct or apply the theory.

    Was teleology even required? Maybe not for the pornography
    and the foodstuffs, but some economists will point out that
    no one really wants a post-hole digger - what they really
    want are postholes, and that the desire for a post-hole
    digger is merely instrumental. Hence, teleology is
    necessary here.

    Second example: Rabbits eat grass. Cows eat grass. Foxes eat
    rabbits but not cows. An ecologist does not need to
    understand WHY foxes don't eat cows to model this ecology.
    Nor does he need to understand why this particular ecosystem
    doesn't contain wolves. [snip]

    Quoted message said:
    Quoted message said:

    Now it is true that the second law can be
    reductionistically explained by statistical mechanics,
    based on the work of Maxwell, Boltzmann, and Gibbs.

    I will be rather picky here and take issue with your use
    of the word "explained," which implies a sort of
    mechanical truism in the reductionistic paradigm. I would
    say that these folks did a great job of reductionistically
    modeling the effects of the second law, but that their
    models are ultimately insufficient as explanations because
    they fail to consider the top down effects that drive self-
    organization.

    In criticising the reductionistic explanation of the second
    law because it doesn't deal with self-organization, you are
    making the (unwarranted IMO) assumption that the second law
    OUGHT to deal with self-organization. Geez! Will you give
    that poor overworked law a breather? The second law doesn't
    have to help explain everything.

    Quoted message said:


    Quoted message said:

    And, it is also true that Einstein and others have
    explored the implications of that reduction at scales
    where a well-defined temperature no longer exists. They
    find fluctuations. Big deal. The second law is only
    approximately true when you try to apply it to
    situations where it is no longer applicable. It is still
    as much a law as Newton's gravitation, or, for that
    matter, quantum mechanics or Einstein's gravitation,
    both of which are expected to fail at the Planck length
    and/or Planck mass.

    If laws are not meant to reflect universalities, then I
    suggest that they get a different term indicating that
    they are contingent.

    I am not aware of any non-contingent laws. Could you give
    an example? AFAIK, the energy and momentum conservation
    laws are also suspected to fail at Planck scales, and they
    are limited by the Heisenberg principle at the atomic
    scale. [snip]

    Quoted message said:
    Quoted message said:

    So, you want to claim that your favorite new macro-level
    "law" is an extension of the second law of
    thermodynamics? [snip] I would prefer that you announce
    your results as a new law of nature, rather than further
    overloading the term "entropy" and claiming to have
    merely extended the second law. It will create less
    confusion.

    I have had plenty of discussions on this issue, and I have
    an issue with your position (with which I think Tim
    agrees) that nobody has answered to my satisfaction. What
    would be the point of articulating a fourth law that
    completely implies the second law? It would be like having
    a law against murder and a second law against murder with
    a knife.

    You raise an interesting point. I have two points to make in
    response that I hope will be equally interesting. But first
    let me say that I generally agree with your position. Your
    hypothetical fourth law is better described as an extended
    second law.

    My first (hopably interesting) point: In axiomatic
    developments of thermodynamics, you will find something
    called the Zeroth Law. It states that two bodies in contact
    will eventually come to thermal equilibrium. The odd thing
    is that the Zeroth Law is apparently implied by the Second.
    After all, isn't heat flow from hot to cold bodies
    frequently given as one example of the Second Law? So why
    did the axiomatizers feel the need to invent a Zeroth law?

    I'm not sure whether the answer should be classified as
    pedagogical or as philosophical. It turns out that you can't
    define temperature without the prior notion of thermal
    equilibrium. And, as I have stated, you can't define entropy
    without first defining temperature. So, a watered down
    Second law - called the Zeroth law - is a prerequisite to
    even understanding what the Second law, in its current
    generality, says.

    It may turn out that your hypothetical Fourth law will say
    that the "superentropy" of the universe is always
    increasing, but the new concept of "superentropy" cannot
    even be defined without prior understanding of the classical
    Second law. In which case, the axiomatizers may want to keep
    the Second and Fourth laws separate.

    Second (hopably interesting) point: Instead of defining a
    new concept like "superentropy", it seems more likely that
    your fourth law will simply extend the current definition of
    entropy to cover cases in which entropy cannot currently be
    defined. As I understand it, these cases are those in which
    temperature is ill-defined, that is, cases in which the
    Zeroth law fails. But statistical mechanics already tells us
    quite a bit about the nature of the unavoidable fluctuations
    in local RMS kinetic energy. This suggests what the new
    definition of entropy should look like. It will be classical
    entropy plus a fluctuation term (which goes to zero in the
    classical case).

    It might work. Think the physicists will appreciate the help
    of an ecologist and an ex-computer-programmer? ;-)

  13. in article [email hidden], Jim Menegay at
    [email hidden] wrote on 3/25/04 8:49 AM:

    Quoted message said:

    Guy Hoelzer <[email hidden]> wrote in message
    news:<[email hidden]>...

    Quoted message said:

    in article [email hidden], Jim Menegay
    at [email hidden] wrote on 3/23/04 4:44 PM:

    Quoted message said:

    Thanks for the heads-up on Stanley and Econo-physics. I
    believe, after considerable searching, that you are
    wrong that he is a Nobelist, but he certainly does not
    appear to be a lightweight.

    I may be wrong about his Nobel-ness, but you are right
    that he could not possibly be considered a lightweight. I
    though he was one of three theoretical physicists who won
    the Nobel prize for development of renormalization group
    analysis.

    I believe, after more searching, that Kenneth Wilson is
    the only person to receive a Nobel prize based on the
    renormalization group.

    Quoted message said:

    If you are not familiar with this method you might find
    it very interesting.

    I'm familiar with Wilson's work from Paul Davies' book,
    "The New Physics".

    Quoted message said:

    The claim for the method, which has been deemed valid by
    the theoretical physics community, is that it can prove
    with certainty that all systems with a particular, small
    set of rules will have certain characteristic tendencies
    regardless of the other details of the systems. In other
    words, it claims to be a proof of inductive validity,
    which was previously thought to be impossible based in
    part on Popper's philosophy.

    But this is new to me. References would be appreciated.

    The only readable (for me) thing I know of on
    renormalization group analysis
    is:

    Stanley, E. 1999. Scaling, universality, and
    renormalization: Three pillars of modern critical phenomena.
    Reviews of Modern Physics, Vol. 71, No. 2

    Quoted message said:

    Gee, those physicists are busy and clever people. Solving
    problems in economics, theology, and now philosophy.
    Someday, maybe, they will crack turbulence.

    It is interesting that you mention turbulence, because I
    think many feel it is an aspect of the same problem, and
    that the physics of complexity will address if not explain
    all of these phenomena.

    Quoted message said:

    And they have so much insight into the issues in other
    fields! The one econophysics paper I have read so far (It
    was listed on the WEB site as paper-of-the-month.) was
    more of a critique of classical economics than a positive
    contribution. It expressed horror that the supply and
    demand curves that the author had encountered in textbooks
    were drawn without error bars. Now THAT is a helpful
    suggestion!

    I begin to understand the reaction of psychologists,
    anthropologists, and sociologists when Sociobiology was
    published.

    That is a nice analogy.

    Best Wishes,

    Guy

  14. in article [email hidden], Jim Menegay at
    [email hidden] wrote on 3/25/04 8:49 AM:

    Quoted message said:

    Guy Hoelzer <[email hidden]> wrote in message
    news:<[email hidden]>...

    Quoted message said:

    in article [email hidden], Jim Menegay
    at [email hidden] wrote on 3/23/04 10:43 PM:

    Quoted message said:

    Tim Tyler <[email hidden]> wrote in message
    news:<[email hidden]>...
    > Jim Menegay <[email hidden]> wrote or quoted:
    > [snip much throughout] [TT] What we are mostly
    > proposing is *new* laws of thermodynamics.

    I have to quibble! What you guys are proposing are new
    laws of dynamics. These laws should properly be called
    "thermodynamic" laws only if you expect to test them
    using a thermometer! More on this below.

    This is a pretty blunt statement. I agree that it will be
    important to take the temperatures of dynamical systems,

    Agree with who? Not me.

    You wrote:

    "These laws should properly be called "thermodynamic" laws
    only if you expect to test them using a thermometer!"

    I agreed with YOU, and went on to point out that for this
    reason "it will be important to take the temperatures of
    dynamical systems" to study them as thermodynamic phenomena.

    Quoted message said:

    What I said is that it is essential to take the
    temperature of a "thermodynamic" system. You can leave
    thermometer at home if you are studying a generic
    dynamical system, for all I care.

    You seem to have lost the thread of my point. My claim is
    that all dynamical systems are thermodynamic phenomena (and
    I think this claim is consistent with the views of the
    founders of thermodynamics theory). You responded that it
    would then be important to be able to take their
    temperatures, and I agreed.

    Quoted message said:
    Quoted message said:

    and to study how they change as their temperatures
    change, but this shouldn't define the limits of empirical
    research on complex systems [I agree] any more than
    taking temperatures has limited previous research in
    thermodynamics.

    But I would claim that taking temperatures DELIMITS
    thermodynamics, based as it is on three key concepts -
    temperature, heat, and entropy. I'm pretty sure heat and
    entropy cannot even be defined at the macro level without
    invoking temperature.

    This is why I agreed that it will be important to take the
    temperatures of complex dynamical systems if they are to be
    understood as thermodynamic phenomena.

    Quoted message said:
    Quoted message said:
    Quoted message said:

    I only suggest economic models when there is inevitably
    teleology involved in the description of the low-level
    units, but the details of what those low-level units
    "desire" is laced with variation and contingency.

    This all seems logical to me. Very interesting. IMHO we
    don't yet know of any simple (not dynamical or composed
    of interacting parts) "low-level units." We don't yet
    know, for example, whether quarks or photons are
    decomposable. Perhaps the requirements for teleology of
    the parts go beyond complexity. Do you have an objective
    way of assessing the teleology of parts, or a theoretical
    basis for the minimal aspects of a thing that would imbue
    it with teleology?

    Talking about "decomposability" misses the point, IMO. The
    real question is whether we (as scientists and theorists)
    want to decompose beyond a particular point. The same
    applies to whether to use teleology in the description of
    the part.

    While I disagree with this view, it would seem to support
    the point I was making because it permits me to assume that
    the parts of any system are teleological. This would then
    lead to the conclusion that any system, including those that
    you include as thermodynamic, are not different (as you
    presumed above) from economics or biology.

    Quoted message said:

    Example: John likes popcorn. For that reason, he buys it.
    An economist needs a little more information than this -
    for example, how much is he willing to pay? But the
    economist doesn't need and doesn't want a reductionist
    explanation of John's desires, nor does the economist feel
    that progress has been made if the reductionist
    explanation removes the teleology. The economist has all
    the information he needs about popcorn, and is ready to
    move on to other commodities such as poppyseed rolls,
    pornography, and post-hole diggers. A reductionist
    explanation would not economize on the data required to
    construct or apply the theory.

    That is a fine example of the limits to reductionism, which
    I argue applies to every phenomenon in the universe with the
    possible exception of non-decomposable, fundamental
    particles (if they exist).

    Quoted message said:

    Was teleology even required? Maybe not for the pornography
    and the foodstuffs, but some economists will point out
    that no one really wants a post-hole digger - what they
    really want are postholes, and that the desire for a post-
    hole digger is merely instrumental. Hence, teleology is
    necessary here.

    Second example: Rabbits eat grass. Cows eat grass. Foxes
    eat rabbits but not cows. An ecologist does not need to
    understand WHY foxes don't eat cows to model this ecology.
    Nor does he need to understand why this particular
    ecosystem doesn't contain wolves.

    This is another nice example that I think reflects a
    universal law.

    Quoted message said:
    Quoted message said:
    Quoted message said:

    Now it is true that the second law can be
    reductionistically explained by statistical mechanics,
    based on the work of Maxwell, Boltzmann, and Gibbs.

    I will be rather picky here and take issue with your use
    of the word "explained," which implies a sort of
    mechanical truism in the reductionistic paradigm. I would
    say that these folks did a great job of
    reductionistically modeling the effects of the second
    law, but that their models are ultimately insufficient as
    explanations because they fail to consider the top down
    effects that drive self-organization.

    In criticising the reductionistic explanation of the
    second law because it doesn't deal with self-organization,
    you are making the (unwarranted IMO) assumption that the
    second law OUGHT to deal with self-organization. Geez!
    Will you give that poor overworked law a breather? The
    second law doesn't have to help explain everything.

    I explained why my view (not that I am the source of this
    view) is more parsimonious than adding an additional law
    below. I would say "Geez" to those who want to unnecessarily
    add more and more laws to the list.

    Quoted message said:
    Quoted message said:
    Quoted message said:

    And, it is also true that Einstein and others have
    explored the implications of that reduction at scales
    where a well-defined temperature no longer exists. They
    find fluctuations. Big deal. The second law is only
    approximately true when you try to apply it to
    situations where it is no longer applicable. It is still
    as much a law as Newton's gravitation, or, for that
    matter, quantum mechanics or Einstein's gravitation,
    both of which are expected to fail at the Planck length
    and/or Planck mass.

    If laws are not meant to reflect universalities, then I
    suggest that they get a different term indicating that
    they are contingent.

    I am not aware of any non-contingent laws. Could you give
    an example? AFAIK, the energy and momentum conservation
    laws are also suspected to fail at Planck scales, and
    they are limited by the Heisenberg principle at the
    atomic scale.

    You may know more about the arguments/evidence than me on
    this front, and I would like to know if I am missing
    something that could alter my view. However, at the moment I
    am under the impression that the laws of thermodynamics are
    argued to be universal and without any contingencies, at
    least in this universe. Suspicions that they may "fail at
    Planck scales" are not enough to undermine my current view,
    given what I consider to be its extraordinary explanatory
    power and logical support. It also seems to me that the
    Heisenberg principle is about uncertainty and the
    availability of information, and I don't see how it is in
    any way inconsistent with my current view.

    Quoted message said:
    Quoted message said:
    Quoted message said:

    So, you want to claim that your favorite new macro-level
    "law" is an extension of the second law of
    thermodynamics? [snip] I would prefer that you announce
    your results as a new law of nature, rather than further
    overloading the term "entropy" and claiming to have
    merely extended the second law. It will create less
    confusion.

    I have had plenty of discussions on this issue, and I
    have an issue with your position (with which I think Tim
    agrees) that nobody has answered to my satisfaction. What
    would be the point of articulating a fourth law that
    completely implies the second law? It would be like
    having a law against murder and a second law against
    murder with a knife.

    You raise an interesting point. I have two points to make
    in response that I hope will be equally interesting. But
    first let me say that I generally agree with your
    position. Your hypothetical fourth law is better described
    as an extended second law.

    My first (hopably interesting) point: In axiomatic
    developments of thermodynamics, you will find something
    called the Zeroth Law. It states that two bodies in
    contact will eventually come to thermal equilibrium. The
    odd thing is that the Zeroth Law is apparently implied by
    the Second. After all, isn't heat flow from hot to cold
    bodies frequently given as one example of the Second Law?
    So why did the axiomatizers feel the need to invent a
    Zeroth law?

    Good point. Maybe it is reasonable to be less than
    parsimonious in enumerating the list of thermodynamic laws
    for the sake of reflecting the rational basis for the
    conceptualization of the roots of the laws.

    Quoted message said:

    I'm not sure whether the answer should be classified as
    pedagogical or as philosophical. It turns out that you
    can't define temperature without the prior notion of
    thermal equilibrium. And, as I have stated, you can't
    define entropy without first defining temperature. So, a
    watered down Second law - called the Zeroth law - is a
    prerequisite to even understanding what the Second law, in
    its current generality, says.

    Right.

    Quoted message said:

    It may turn out that your hypothetical Fourth law will say
    that the "superentropy" of the universe is always
    increasing, but the new concept of "superentropy" cannot
    even be defined without prior understanding of the
    classical Second law. In which case, the axiomatizers may
    want to keep the Second and Fourth laws separate.

    Right; although I don't see the fourth law, or extended
    second law, as supporting a concept like "super-entropy."
    The distinction between rate and direction seems to be
    different in kind, although I suppose it is possible that
    the most transparent argument will require establishing
    direction before rate maximization.

    Quoted message said:

    Second (hopably interesting) point: Instead of defining a
    new concept like "superentropy", it seems more likely that
    your fourth law will simply extend the current definition
    of entropy to cover cases in which entropy cannot
    currently be defined. As I understand it, these cases are
    those in which temperature is ill-defined, that is, cases
    in which the Zeroth law fails. But statistical mechanics
    already tells us quite a bit about the nature of the
    unavoidable fluctuations in local RMS kinetic energy. This
    suggests what the new definition of entropy should look
    like. It will be classical entropy plus a fluctuation term
    (which goes to zero in the classical case).

    As I understand it, entropy cannot be concretely defined for
    anything other than a closed system. The closest thing we
    know of that satisfies this condition is the universe as a
    whole, which is why this is the only level at which I argue
    the prediction of the extended second law applies. The
    extension of the law (rate maximization as opposed to merely
    direction) has great implications for smaller scale
    phenomena, which are not implied by the classical
    articulation of the law. Indeed, I think the reason many of
    "us" arguing for extending thermodynamic laws in one way or
    another are driven by our desires for more fundamental
    explanations of phenomena within the universe.

    Quoted message said:

    It might work. Think the physicists will appreciate the
    help of an ecologist and an ex-computer-programmer? ;-)

    More and more.

    Regards,

    Guy

  15. Jim Menegay <[email hidden]> wrote or quoted:

    Quoted message said:

    Tim Tyler <[email hidden]> wrote in message
    news:<[email hidden]>...

    Quoted message said:
    Quoted message said:

    [snip] Re: your idea of fitness increasing. You haven't
    explained this - but - IMO - it would translate into
    organisms having more and more surviving offspring as
    time passed.

    I believe you need a continuously-expanding -
    environment to pull that trick off for very long ;-)

    Nope. Just a continuously deteriorating environment.
    Fisher's "fundamental theorem" says that the genetical
    component of fitness is non-decreasing. But he avoids
    having continuously increasing populations by claiming
    that the environment is continually deteriorating. Only
    recently have theorists realized that Fisher was including
    the average fitness of competing conspecifics as a
    component of the environment. So, we have a "Red Queen"
    race - fitness continually increases, but number of
    offspring do not.

    I prefer the presentation on:

    peregrine.dkFISH.HTM

    It says - among other things - that Fisher's "fundamental
    theorem" is toast.

    ;-)
    --
    __________
    |im |yler timtyler.orgtimtyler.org [email hidden] Remove
    lock to reply.

  16. Jim Menegay <[email hidden]> wrote or quoted:

    Quoted message said:

    Tim Tyler <[email hidden]> wrote in message
    news:<[email hidden]>...

    Quoted message said:
    Quoted message said:

    [snip] Imagine for a moment that the second law had not
    yet been created.

    Crystalization is consistent with the Zeroth and First
    laws of thermodynamics - what need is there for a
    "second law"?

    The answer is that the second law provides more
    information about the behaviour of the system. It
    doesn't change the temporal evolution of the system, but
    rather represents an observation about its behaviour.

    I have to disagree. Without the second law, there would be
    no reason not to expect a crystal to dissolve (absorbing
    heat) in a supersaturated solution. No reason not to
    expect a crystal to grow in an unsaturated solution. It is
    the second law that provides an "arrow" to the temporal
    evolution of the system.

    Without the second law, there would be no "tendency to
    seek the state of lowest energy". After all, following the
    first law, energy is conserved, so all states have the
    same energy. The zeroth law doesn't provide an arrow
    either, for anything except temperature.

    But you HAVE TO have already known this. So, I must be
    misinterpreting what you wrote. But how?

    I was talking about a time when a society had discovered the
    "Zeroth and First laws of thermodynamics" - but had not yet
    discovered the second law.

    Crystals would have been behaving much the same way since
    the year dot - regardless of their knowledge of
    thermodynamics.

    You were arguing there was no need for more laws - since the
    existing ones had crystal formation covered.

    But the same argument in the society I mention would
    apparently suggest there was no need for the second law.

    Crystal formation is consistent with the second law - but
    the second law doesn't tell us all the interesting facts
    about the thermodynamics of supersaturated solutions.

    In particular existing thermodynamics *doesn't* tell us what
    happens to the entropy of the system when you introduce a
    self-organising system -
    i.e. a crystal seed.

    That's what the thermodynamics of complex systems is for.

    It will tell us that - when self-organising systems are
    introduced:

    * the entropy goes up;
    * the entropy goes up rapidly;
    * the entropy goes up with increasing rapidity as time
    passes while the SOS is establishing itself;
    * the rapidity of the entropy increase depends on the
    sophistication of the complex system in question - with
    complex ecosystems being at the top of the scale.

    Incidentally, the second law doesn't exactly say there's a
    tendency to seek out the lowest energy states. What it says
    is that entropy doesn't increase. The second law is quite
    happy with entropy sitting still and not doing very much -
    and that's rather different from "seeking out the lowest
    energy states" - IMHO.

    This is one reason why a thermodynamic characterisation of
    complex adaptive systems is needed. Dissipative structures
    *do* actively encourage entropy to increase. This behaviour
    is *not* predicted by the second law. The second law
    (perfectly correctly) has nothing to say about the behaviour
    of complex systems.
    --
    __________
    |im |yler timtyler.orgtimtyler.org [email hidden] Remove
    lock to reply.

  17. "Jim Menegay" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    I am myself working on an idea that has the mutation rate
    in the role of temperature and fitness in the role of
    enthalpy.

    An interesting and impressive ideation!

    "Fitness as enthalpy" --- that might at least give John
    Edser - the biggest "absolute fitness" fanatic that
    phylogeny has this far forged - a reason to rejoice. ;-)

    P

  18. Guy Hoelzer <[email hidden]> wrote in message news:<[email hidden]>...

    Quoted message said:

    As I understand it, entropy cannot be concretely defined
    for anything other than a closed system.

    I believe this is correct with respect to classical (pre-
    Prigogine) thermodynamics.

    Quoted message said:

    The closest thing we know of that satisfies this condition
    [closed system] is the universe as a whole ...

    I believe this is incorrect. Perhaps you are confusing
    "closed" systems with "isolated" systems.

    A "closed system" is one that does not exchange matter with
    its surroundings. It may exchange heat and work with its
    surroundings. (We need to measure these flows, which may be
    difficult in practice.)

    Examples of closed systems are the universe, the solar
    system (approximately closed), or the contents of any
    stoppered beaker.

    In principle, entropy can be measured for any closed system
    by integrating dS = dQrev / T.

    Qrev is the heat absorbed (reversibly) by the system as the
    temperature is raised. The lower end of the range of
    integration is at T=0, by the third law. In practice, you
    start from any state where the entropy is already known.

    There is nothing particularly mysterious or inaccessible
    about classical entropy. But its definition does presume
    that you can measure heat flow and temperature. This means
    that you have to be close to (or at) thermal equilibrium.
    You don't need to be close to chemical equilibrium, as long
    as no chemical reactions are occuring.

  19. Guy Hoelzer <[email hidden]> wrote in message news:<[email hidden]>...

    Quoted message said:

    However, at the moment I am under the impression that the
    laws of thermodynamics are argued to be universal and
    without any contingencies, at least in this universe.

    But earlier in this thread said:

    Anyway, we are not /really/ talking about physics. The
    second law of thermodynamics isn't /really/ a law and is
    isn't /really/ physics.

    Its a statement about statistical tendencies among systems
    with large numbers of components.

    It is not a "law" - since it can be broken - especially on
    small scales - and it has more to do with statistics than
    it does to do with physics.

    :-) Guy, I'd like to introduce Tim. Tim, this is Guy. Have
    :fun you two,
    but play nice. Perhaps you both can find some middle ground
    - you are welcome to join my position that the laws of
    thermodynamics really are laws, but that they only apply to
    the situations that they claim to apply to - that is, in
    Guy's language, they have contingencies.

  20. Jim Menegay <[email hidden]> wrote or quoted:

    Quoted message said:

    But earlier in this thread, Tim Tyler wrote:

    Quoted message said:
    Quoted message said:

    Anyway, we are not /really/ talking about physics. The
    second law of thermodynamics isn't /really/ a law and is
    isn't /really/ physics.

    Its a statement about statistical tendencies among
    systems with large numbers of components.

    It is not a "law" - since it can be broken - especially
    on small scales - and it has more to do with statistics
    than it does to do with physics.

    :-) Guy, I'd like to introduce Tim. Tim, this is Guy. Have
    :fun you two,
    but play nice. Perhaps you both can find some middle
    ground - you are welcome to join my position that the laws
    of thermodynamics really are laws, but that they only
    apply to the situations that they claim to apply to - that
    is, in Guy's language, they have contingencies.

    I attribute my charaterisation of the second "law" to
    Boltzman:

    ``Boltzmann resolves the conflict by stating that the Second
    Law of Thermodynamics is not really a law at all. It is more
    of a statistical recommendation of what is likely to occur.
    It is very improbable that a system can go from great
    entropy to less entropy, but it is not necessarily
    impossible.''

    Boltzmann's reinterpretation of the second law is the one
    that has become standardly taught as its theoretical
    underpinning.

    It's best to totally dispense with the idea of the second
    law as a law of physics. It is a result of the laws of
    physics being reversible. You get the exact same "law" in
    any reversible system - regardless of the other details of
    the laws of physics.

    The second law is thus best seen as primarily statistical
    in nature.
    --
    __________
    |im |yler timtyler.orgtimtyler.org [email hidden] Remove
    lock to reply.

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