Dynamics of Complex Systems by Yaneer Bar-Yam

[Owen Densmore]

I've been looking at/for complexity books that are textbooks or  
similarly technical/mathematical.  The recent Newman, Barabasi &  
Watts collection The Structure and Dynamics of Networks is pretty  
good but I would like something broader, covering the "Complex  
Systems" world.

Bar Yam's original book:
http://tinyurl.com/mmxwp
   or
http://www.amazon.com/gp/product/0813341213/sr=1-1/qid=1153334623/ 
ref=sr_1_1/104-7070581-5619133?ie=UTF8
is the best I know of.  Anyone know of another?

     -- Owen

Owen Densmore
http://backspaces.net - http://redfish.com - http://friam.org

[Owen Densmore]

Frankly, I'm disappointed.

The FRIAM list has been through several very philosophical  
conversations over 3-4 weeks, all purporting to be "complex".  Yet  
when I ask for a formal treatment, I get no answer.

Does this mean, for complexity, there's no There There?

Surely there is some interesting formalism we can use for  
complexity.  Robert Holmes suggested a great book to us a while back  
which I had forgotten in my initial email:
   David MacKay: Information Theory, Inference, and Learning Algorithms
   http://www.inference.phy.cam.ac.uk/mackay/itila/

Do we all talk about complexity yet have no basis for it?

     -- Owen

Owen Densmore
http://backspaces.net - http://redfish.com - http://friam.org


On Jul 19, 2006, at 1:01 PM, Owen Densmore wrote:

> I've been looking at/for complexity books that are textbooks or
> similarly technical/mathematical.  The recent Newman, Barabasi &
> Watts collection The Structure and Dynamics of Networks is pretty
> good but I would like something broader, covering the "Complex
> Systems" world.
>
> Bar Yam's original book:
> http://tinyurl.com/mmxwp
>    or
> http://www.amazon.com/gp/product/0813341213/sr=1-1/qid=1153334623/
> ref=sr_1_1/104-7070581-5619133?ie=UTF8
> is the best I know of.  Anyone know of another?
>
>      -- Owen
>
> Owen Densmore
> http://backspaces.net - http://redfish.com - http://friam.org
>
>
>
> ============================================================
> FRIAM Applied Complexity Group listserv
> Meets Fridays 9a-11:30 at cafe at St. John's College
> lectures, archives, unsubscribe, maps at http://www.friam.org

[Marko Rodriguez]

Complexity is a dead concept.

Marko A. Rodriguez
T-13: Complex Systems Group
Los Alamos National Laboratory
Phone [phone]
http://www.soe.ucsc.edu/~okram


On Jul 21, 2006, at 1:15 PM, Owen Densmore wrote:

> Frankly, I'm disappointed.
>
> The FRIAM list has been through several very philosophical
> conversations over 3-4 weeks, all purporting to be "complex".  Yet
> when I ask for a formal treatment, I get no answer.
>
> Does this mean, for complexity, there's no There There?
>
> Surely there is some interesting formalism we can use for
> complexity.  Robert Holmes suggested a great book to us a while back
> which I had forgotten in my initial email:
>    David MacKay: Information Theory, Inference, and Learning  
> Algorithms
>    http://www.inference.phy.cam.ac.uk/mackay/itila/
>
> Do we all talk about complexity yet have no basis for it?
>
>      -- Owen
>
> Owen Densmore
> http://backspaces.net - http://redfish.com - http://friam.org
>
>
> On Jul 19, 2006, at 1:01 PM, Owen Densmore wrote:
>
>> I've been looking at/for complexity books that are textbooks or
>> similarly technical/mathematical.  The recent Newman, Barabasi &
>> Watts collection The Structure and Dynamics of Networks is pretty
>> good but I would like something broader, covering the "Complex
>> Systems" world.
>>
>> Bar Yam's original book:
>> http://tinyurl.com/mmxwp
>>    or
>> http://www.amazon.com/gp/product/0813341213/sr=1-1/qid=1153334623/
>> ref=sr_1_1/104-7070581-5619133?ie=UTF8
>> is the best I know of.  Anyone know of another?
>>
>>      -- Owen
>>
>> Owen Densmore
>> http://backspaces.net - http://redfish.com - http://friam.org
>>
>>
>>
>> ============================================================
>> FRIAM Applied Complexity Group listserv
>> Meets Fridays 9a-11:30 at cafe at St. John's College
>> lectures, archives, unsubscribe, maps at http://www.friam.org
>
>
> ============================================================
> FRIAM Applied Complexity Group listserv
> Meets Fridays 9a-11:30 at cafe at St. John's College
> lectures, archives, unsubscribe, maps at http://www.friam.org

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[Günther Greindl-2]

Hello everybody,

I've been lurking on the list for quite some
time now, and have always enjoyed reading the interesting
discussions going on here (this is definitely my favourite
mailing list :-)

So I guess it's time to join the fray.

My academic background is law and computer science.
In October I'll start my Ph.D. in Vienna, Austria
(where I'm from) at the Insitute of Philosophy of
Science of the Uni Wien.

I want to analyse human complex adaptive systems, especially
diffusion of culture/norms and criteria for stable societies.
My main methodology will be agent based modelling, though I
want to draw on the theoretical work of many pertinent disciplines.

Well then ... looking forward to many discussions,
G?nther

[Günther Greindl-2]

Hi Owen,

if I may recommend a book:

Complexity: Hierarchical Structures and Scaling in Physics (Cambridge
Nonlinear Science Series)
by
Remo Badii, Antonio Politi

Here the amazon link:
http://tinyurl.com/eb78d


Site of the author:
http://www.geocities.com/badii_remo/


Despite the title, the book does not only draw examples from physics,
but also from other domains, like biology.
I became aware of the book after my extended rummagings
through Cosma Shalizi's site (especially his reviews, notebooks,
papers,... all very interesting :-)

Here's Cosma's review of the book:
http://www.cscs.umich.edu/~crshalizi/reviews/badii-and-politi/

And if I may quote the last sentence of the review:

"I wouldn't want to teach such a course to those who hadn't previously
been exposed to nonlinear dynamics, or who were unfamiliar with
statistical mechanics at the level of Part I of Landau and Lifshitz, say
second year graduate students in physics and applied math; but it is,
hands down, the best book currently available to teach such critters
about complexity, and even more seasoned, not to say jaded, researchers
will find it useful as a reference."

Hope this helps,
G?nther

Owen Densmore wrote:

> Frankly, I'm disappointed.
>
> The FRIAM list has been through several very philosophical  
> conversations over 3-4 weeks, all purporting to be "complex".  Yet  
> when I ask for a formal treatment, I get no answer.
>
> Does this mean, for complexity, there's no There There?
>
> Surely there is some interesting formalism we can use for  
> complexity.  Robert Holmes suggested a great book to us a while back  
> which I had forgotten in my initial email:
>    David MacKay: Information Theory, Inference, and Learning Algorithms
>    http://www.inference.phy.cam.ac.uk/mackay/itila/
>
> Do we all talk about complexity yet have no basis for it?
>
>      -- Owen
>
> Owen Densmore
> http://backspaces.net - http://redfish.com - http://friam.org
>
>
> On Jul 19, 2006, at 1:01 PM, Owen Densmore wrote:
>
>> I've been looking at/for complexity books that are textbooks or
>> similarly technical/mathematical.  The recent Newman, Barabasi &
>> Watts collection The Structure and Dynamics of Networks is pretty
>> good but I would like something broader, covering the "Complex
>> Systems" world.
>>
>> Bar Yam's original book:
>> http://tinyurl.com/mmxwp
>>    or
>> http://www.amazon.com/gp/product/0813341213/sr=1-1/qid=1153334623/
>> ref=sr_1_1/104-7070581-5619133?ie=UTF8
>> is the best I know of.  Anyone know of another?
>>
>>      -- Owen
>>
>> Owen Densmore
>> http://backspaces.net - http://redfish.com - http://friam.org
>>
>>
>>
>> ============================================================
>> FRIAM Applied Complexity Group listserv
>> Meets Fridays 9a-11:30 at cafe at St. John's College
>> lectures, archives, unsubscribe, maps at http://www.friam.org
>
>
> ============================================================
> FRIAM Applied Complexity Group listserv
> Meets Fridays 9a-11:30 at cafe at St. John's College
> lectures, archives, unsubscribe, maps at http://www.friam.org
>
>

[Jochen Fromm-3]

 
Complexity is not "dead". Scientists have always
been interested in complex systems, and will always
be. Only the degree increases, the frontier is
shifting. And it is of course inherently difficult
to define complexity precisely (because something
is complex if you cannot describe it in a simple way),
or to grasp it clearly with a formalism.

The "new" sciences of complexity are nothing else
but the exploration of complex systems with computers.
Just as telescopes allow us to recognize large
scale structures, or microcopes and particle
accelerators allow us to resolve tiny structures,
computers allows us to investigate more complex
structures.

The best formalisms here are agents and cellular
automata. The exploration of both are only possible
with fast computers. As you know, the goal is
find simple models with complex results: agent based
models like "the (Iterated) Prisoner's Dilemma",
"the El Farol Model", "the Minority Game", the
"Flocking" or swarm model, the pheronmone (ant)
foraging model, etc.

These models and the different types and forms of
"emergence" play perhaps the rule of fundamental
equations in physics and the natural sciences.
Some of the better books IMHO are (list is not
comprehensive) for..

... Agent based Modelling
Joshua Epstein and Robert Axtell, "Growing Artificial Societies"
Nigel Gilbert and Klaus G. Troitzsch, "Simulation for the Social Scientist"
The MABS (Multi-Agent-Based Simulation) books from Springer's LNAI
Thomas Schelling, "Micromotives and Macrobehavior"
Robert Axelrod, "The Complexity of Cooperation"

... Cellular Automata
Stephen Wolfram, "A New Kind of Science"
Andrew Ilachinski, "Cellular Automata: A Discrete Universe"

-J.

[Owen Densmore]

Wonderful suggestion .. and I had also forgotten Cosma's wonderful  
site.  What a great old soul, although he'd hate to hear that.

He taught the beginning math review of the 2002 summer school and  
fixed in my receptive though weak mind that most of statistics isn't  
worth a whole lot and it should begin with Markov Chains.

     -- Owen

Owen Densmore
http://backspaces.net - http://redfish.com - http://friam.org


On Jul 21, 2006, at 2:06 PM, G?nther Greindl wrote:

> Hi Owen,
>
> if I may recommend a book:
>
> Complexity: Hierarchical Structures and Scaling in Physics (Cambridge
> Nonlinear Science Series)
> by
> Remo Badii, Antonio Politi
>
> Here the amazon link:
> http://tinyurl.com/eb78d
>
>
> Site of the author:
> http://www.geocities.com/badii_remo/
>
>
> Despite the title, the book does not only draw examples from physics,
> but also from other domains, like biology.
> I became aware of the book after my extended rummagings
> through Cosma Shalizi's site (especially his reviews, notebooks,
> papers,... all very interesting :-)
>
> Here's Cosma's review of the book:
> http://www.cscs.umich.edu/~crshalizi/reviews/badii-and-politi/
>
> And if I may quote the last sentence of the review:
>
> "I wouldn't want to teach such a course to those who hadn't previously
> been exposed to nonlinear dynamics, or who were unfamiliar with
> statistical mechanics at the level of Part I of Landau and  
> Lifshitz, say
> second year graduate students in physics and applied math; but it is,
> hands down, the best book currently available to teach such critters
> about complexity, and even more seasoned, not to say jaded,  
> researchers
> will find it useful as a reference."
>
> Hope this helps,
> G?nther
>
> Owen Densmore wrote:
>> Frankly, I'm disappointed.
>>
>> The FRIAM list has been through several very philosophical
>> conversations over 3-4 weeks, all purporting to be "complex".  Yet
>> when I ask for a formal treatment, I get no answer.
>>
>> Does this mean, for complexity, there's no There There?
>>
>> Surely there is some interesting formalism we can use for
>> complexity.  Robert Holmes suggested a great book to us a while back
>> which I had forgotten in my initial email:
>>    David MacKay: Information Theory, Inference, and Learning  
>> Algorithms
>>    http://www.inference.phy.cam.ac.uk/mackay/itila/
>>
>> Do we all talk about complexity yet have no basis for it?
>>
>>      -- Owen
>>
>> Owen Densmore
>> http://backspaces.net - http://redfish.com - http://friam.org
>>
>>
>> On Jul 19, 2006, at 1:01 PM, Owen Densmore wrote:
>>
>>> I've been looking at/for complexity books that are textbooks or
>>> similarly technical/mathematical.  The recent Newman, Barabasi &
>>> Watts collection The Structure and Dynamics of Networks is pretty
>>> good but I would like something broader, covering the "Complex
>>> Systems" world.
>>>
>>> Bar Yam's original book:
>>> http://tinyurl.com/mmxwp
>>>    or
>>> http://www.amazon.com/gp/product/0813341213/sr=1-1/qid=1153334623/
>>> ref=sr_1_1/104-7070581-5619133?ie=UTF8
>>> is the best I know of.  Anyone know of another?
>>>
>>>      -- Owen
>>>
>>> Owen Densmore
>>> http://backspaces.net - http://redfish.com - http://friam.org
>>>
>>>
>>>
>>> ============================================================
>>> FRIAM Applied Complexity Group listserv
>>> Meets Fridays 9a-11:30 at cafe at St. John's College
>>> lectures, archives, unsubscribe, maps at http://www.friam.org
>>
>>
>> ============================================================
>> FRIAM Applied Complexity Group listserv
>> Meets Fridays 9a-11:30 at cafe at St. John's College
>> lectures, archives, unsubscribe, maps at http://www.friam.org
>>
>>
>
>
> ============================================================
> FRIAM Applied Complexity Group listserv
> Meets Fridays 9a-11:30 at cafe at St. John's College
> lectures, archives, unsubscribe, maps at http://www.friam.org

[Martin C. Martin-2]

Owen Densmore wrote:
> Frankly, I'm disappointed.
>
> The FRIAM list has been through several very philosophical  
> conversations over 3-4 weeks, all purporting to be "complex".  Yet  
> when I ask for a formal treatment, I get no answer.
>
> Does this mean, for complexity, there's no There There?
>  
Calculus went for over 100 years without a formal definition of either
function or derivative, talking about infinitesimal changes without a
formal definition of infinitesimal.  Worse, at some point in a proof it
would be a mistake to discard infinitesimals as "essentially zero," yet
you always did at the end of the proof.  There were no real rules as to
when you should and when you shouldn't.

Formalization often happens only after a field is well understood and
used, usually not before.

- Martin

[Stephen Guerin]

 
>  Yet when I ask for a formal treatment, I get no answer.

I very much like Hubler's deceptively simple definition of complexity:
        "A complex systems is a system with large throughput of Energy,
Information, Force, .... through a well designed boundary."

His notes from the SFI CSSS school with this definition are here:
http://www.how-why.com/ucs2002/tutorial/


As a restatement of the same ideas that formalizes what "large" means, I would
offer:
        "complexity emerges when a gradient acting on a system exceeds the
capacity of the internal degrees of freedom of the system to dissipate the
gradient".


Is that formal enough? or, does the statement need to be mathematized?

-Steve

________________________________________
Stephen.Guerin at Redfish.com
www.Redfish.com
624 Agua Fria Street, Santa Fe, NM 87501
mobile: [phone]
office: Santa Fe, NM [phone] / London, UK [phone]

[Carl Tollander]

Stephen,

Could you say more about how gradients *act* on a system?

I tend to think of gradients as new (non-adjoint) structure produced by
the application
of constraints between elements in a system.  That is, the constraints
form the context
(the DOF) for the gradient.

I think I may be able to reconcile this with Hubler's definition (some
problems with
that "well designed" part), but the the latter is more challenging.  Are
you saying
that gradients embody agency?  How do we describe the dissipative
capacity of a
degree of freedom so that we can characterize what happens when it
breaks down?

Hmmm, ok, I now think I see how to answer that, but lets see what the
comments are...

Carl

Stephen Guerin wrote:

>  
>  
>>  Yet when I ask for a formal treatment, I get no answer.
>>    
>
> I very much like Hubler's deceptively simple definition of complexity:
> "A complex systems is a system with large throughput of Energy,
> Information, Force, .... through a well designed boundary."
>
> His notes from the SFI CSSS school with this definition are here:
> http://www.how-why.com/ucs2002/tutorial/
>
>
> As a restatement of the same ideas that formalizes what "large" means, I would
> offer:
> "complexity emerges when a gradient acting on a system exceeds the
> capacity of the internal degrees of freedom of the system to dissipate the
> gradient".
>
>
> Is that formal enough? or, does the statement need to be mathematized?
>
> -Steve
>
> ________________________________________
> Stephen.Guerin at Redfish.com
> www.Redfish.com
> 624 Agua Fria Street, Santa Fe, NM 87501
> mobile: [phone]
> office: Santa Fe, NM [phone] / London, UK [phone]
>
>
> ============================================================
> FRIAM Applied Complexity Group listserv
> Meets Fridays 9a-11:30 at cafe at St. John's College
> lectures, archives, unsubscribe, maps at http://www.friam.org
>
>
>
>  

[Phil Henshaw-2]

Steven,

Not sure if it fits, but the type of complex systems I first carefully
studied were natural air currents.  

There's a clear energy gradient involved when sunlight provides heat at
the bottom of a column of air and buoyancy drives the development of
intricate motions.  What I noticed is that the paths of motion evolve
individually by growth processes.  Some small perturbation at an
instability results in a positively reinforced development of movements,
that gives the air a system of solving the problem of getting out of its
own way, to release the gradient.   From observation, it looks like
there are some delays in the right disturbance occurring, perhaps.
Individual currents rising from a floor can develop in what appears to
be erratic and lazy fashion.

I think this behavior probably fits your model somehow, but I don't see
the degrees of freedom or capacities you refer to as the gateway to
relieving any gradient.  

Make any sense?

>
>
>  
> >  Yet when I ask for a formal treatment, I get no answer.
>
> I very much like Hubler's deceptively simple definition of complexity:
> "A complex systems is a system with large throughput of
> Energy, Information, Force, .... through a well designed boundary."
>
> His notes from the SFI CSSS school with this definition are
> here: http://www.how-why.com/ucs2002/tutorial/
>
>
> As a restatement of the same ideas that formalizes what
> "large" means, I would
> offer:
> "complexity emerges when a gradient acting on a system
> exceeds the capacity of the internal degrees of freedom of
> the system to dissipate the gradient".
>
>
> Is that formal enough? or, does the statement need to be mathematized?
>
> -Steve
>
> ________________________________________
> Stephen.Guerin at Redfish.com
> www.Redfish.com
> 624 Agua Fria Street, Santa Fe, NM 87501
> mobile: [phone]
> office: Santa Fe, NM [phone] / London, UK [phone]
>
>
> ============================================================
> FRIAM Applied Complexity Group listserv
> Meets Fridays 9a-11:30 at cafe at St. John's College
> lectures, archives, unsubscribe, maps at http://www.friam.org
>
>

[Robert Holmes]

Models such as Schellings segregation and Axtel and Epsteins artificial
societies typically take place on some bounded checker board through which
nothing flows. By the defintion below are these therefore not complex
systems?

Robert

On 7/21/06, Stephen Guerin <stephen.guerin at redfish.com> wrote:

>
>
> >  Yet when I ask for a formal treatment, I get no answer.
>
> I very much like Hubler's deceptively simple definition of complexity:
>         "A complex systems is a system with large throughput of Energy,
> Information, Force, .... through a well designed boundary."
>
> His notes from the SFI CSSS school with this definition are here:
> http://www.how-why.com/ucs2002/tutorial/
>
>
> As a restatement of the same ideas that formalizes what "large" means, I
> would
> offer:
>         "complexity emerges when a gradient acting on a system exceeds the
> capacity of the internal degrees of freedom of the system to dissipate the
> gradient".
>
>
> Is that formal enough? or, does the statement need to be mathematized?
>
> -Steve
>
> ________________________________________
> Stephen.Guerin at Redfish.com
> www.Redfish.com
> 624 Agua Fria Street, Santa Fe, NM 87501
> mobile: [phone]
> office: Santa Fe, NM [phone] / London, UK [phone]
>
>
> ============================================================
> FRIAM Applied Complexity Group listserv
> Meets Fridays 9a-11:30 at cafe at St. John's College
> lectures, archives, unsubscribe, maps at http://www.friam.org
>

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[Robert Holmes]

On 7/21/06, Owen Densmore <owen at backspaces.net> wrote:
>
> ...
>
> Does this mean, for complexity, there's no There There?
> ...
>
Do we all talk about complexity yet have no basis for it?
>
>      -- Owen



Owen,

You have forgotten the Complexity Koan:

"The core concept of complexity science is that there is no core concept of
complexity science."

Robert
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[Stephen Guerin]

Robert writes:
> Models such as Schellings segregation and Axtel and Epsteins
> artificial societies typically take place on some bounded
> checker board through which nothing flows. By the defintion
> below are these therefore not complex systems?

Yeah, I've been wondering for a few years how to reconcile dissipative
structures with the classic computational models in complexity (eg flocking,
schelling, ant foraging, CAs etc). In particular, what does it mean for a model
to be far-from-equilibrium.

The only thing I have to offer at this point is to look at any particular model
and try to figure out what is flowing through the model and what constitutes a
gradient. In physics, a gradient can be an asymmetric distribution of a
conserved quantity (mass, energy, charge, momentum, etc). The more asymmetric
the distribution is (ie far from equilibrium, low entropy), the more work can
potentially be extracted.

 - In *most* toy ABMs, I think flow is in the updating of the agents and is
probably closely equivalent to energy flow.

 - Gradients in ABM, I suspect, are mappable to asymmetries in the model
description/setup. This can be in the initial configurations of agents or
resources, asymmetries in behavioral rules or asymmetries in agent-agent
communication networks. If you remove asymmetries in your model setup, you will
not get emergent structure in your run.

For example:

In ant foraging, asymmetries are found in the initial placement of the ants, the
location of the nests/food and the forward bias of ant movement.

In Schelling's segregation model, for spatial patterns to exist, agents must
asymmetrically prefer to live near like agents (ie an asymmetry in a behavioral
rule).

To get emergent patterns in the beer game, one needs an asymmetric penalty where
it is more expensive to be out of stock than to hold inventory (asymmetry in
behavioral rule).

In flocking, boids need an asymmetric forward-biased cone of vision and the
asymmetric forward-bias in turning (ie no 180 degree turns) in order to break
symmetry in the system's linear momentum.

In the case of 1D CAs, I'm guessing it's the case that all type-IV CAs have
asymmetric rule tables. Anyone know for sure?

-Steve

> -----Original Message-----
> From: Robert Holmes [mailto:robert at holmesacosta.com]
> Sent: Sunday, July 23, 2006 3:07 PM
> To: The Friday Morning Applied Complexity Coffee Group
> Subject: Re: [FRIAM] formalization of Complexity (was
> Dynamics of ComplexSystems by Yaneer Bar-Yam)
>
> Models such as Schellings segregation and Axtel and Epsteins
> artificial societies typically take place on some bounded
> checker board through which nothing flows. By the defintion
> below are these therefore not complex systems?
>
> Robert
>
>
> On 7/21/06, Stephen Guerin <stephen.guerin at redfish.com> wrote:
>
>
> >  Yet when I ask for a formal treatment, I get no answer.
>
> I very much like Hubler's deceptively simple definition
> of complexity:
>        "A complex systems is a system with large
> throughput of Energy,
> Information, Force, .... through a well designed boundary."
>
> His notes from the SFI CSSS school with this definition
> are here:
> http://www.how-why.com/ucs2002/tutorial/
>
>
> As a restatement of the same ideas that formalizes what
> "large" means, I would
> offer:
>        "complexity emerges when a gradient acting on a
> system exceeds the
> capacity of the internal degrees of freedom of the
> system to dissipate the
> gradient".
>
>
> Is that formal enough? or, does the statement need to
> be mathematized?
>
> -Steve
>
> ________________________________________
> Stephen.Guerin at Redfish.com
> www.Redfish.com
> 624 Agua Fria Street, Santa Fe, NM 87501
> mobile: [phone]
> office: Santa Fe, NM [phone] / London, UK +44 (0)
> 20 7993 4769
>
>
> ============================================================
> FRIAM Applied Complexity Group listserv
> Meets Fridays 9a-11:30 at cafe at St. John's College
> lectures, archives, unsubscribe, maps at
> http://www.friam.org <http://www.friam.org>
>
>
>
>

[Stephen Guerin]

Carl writes:
> Could you say more about how gradients *act* on a system?

Gradients act on the elements (agents) of a system. For example, in physics, a
gradient is equal and opposite to the force at a point acting on an element of a
system. In ABMs, the modeler explicitly defines this interaction by coding the
agent's ability to sense a gradient and to react to it. (eg foraging ants will
detect a pheromone gradient and move uphill in that gradient).

Carl writes:
> Are you saying that gradients embody agency?

I'm not sure "embody" is the correct term. I think gradients are "necessary" for
agency. I agree with Stu's definition of an autonomous agent which:
    1 - measure useful displacements from equilibrium (eg gradient) from which
work can be extracted
    2 - discover devices to couple to those energy sources such that work can be
extracted
    3 - apply work to develop constraints to extract work

But thinking further, the term "embody" may not be off...certainly gradients
embody the potential for agency. eg. Boltzmann (1905) writes that "life
(agency?) is a struggle for the ability to perform work (gradient)..."

-Steve

Boltzmann, L. (1905). The Second Law of Thermodynamics. Populare Schriften.
Essay No. 3 (Address to Imperial Academy of
Science in 1886). Reprinted in English in: Theoretical Physics and Philosophical
Problems, Selected Writings of L. Boltzmann and D. Riedel, Dordrecht.
(referenced from Jorgenson & Fath, 2004)

> -----Original Message-----
> From: Carl Tollander [mailto:carl at plektyx.com]
> Sent: Friday, July 21, 2006 10:36 PM
> To: The Friday Morning Applied Complexity Coffee Group
> Subject: Re: [FRIAM] formalization of Complexity (was
> Dynamics of Complex Systems by Yaneer Bar-Yam)
>
> Stephen,
>
> Could you say more about how gradients *act* on a system?
>
> I tend to think of gradients as new (non-adjoint) structure
> produced by the application of constraints between elements
> in a system.  That is, the constraints form the context (the
> DOF) for the gradient.
>
> I think I may be able to reconcile this with Hubler's
> definition (some problems with that "well designed" part),
> but the the latter is more challenging.  Are you saying that
> gradients embody agency?  How do we describe the dissipative
> capacity of a degree of freedom so that we can characterize
> what happens when it breaks down?
>
> Hmmm, ok, I now think I see how to answer that, but lets see
> what the comments are...
>
> Carl
>
> Stephen Guerin wrote:
> >  
> >  
> >>  Yet when I ask for a formal treatment, I get no answer.
> >>    
> >
> > I very much like Hubler's deceptively simple definition of
> complexity:
> > "A complex systems is a system with large throughput of Energy,
> > Information, Force, .... through a well designed boundary."
> >
> > His notes from the SFI CSSS school with this definition are here:
> > http://www.how-why.com/ucs2002/tutorial/
> >
> >
> > As a restatement of the same ideas that formalizes what
> "large" means,
> > I would
> > offer:
> > "complexity emerges when a gradient acting on a system
> exceeds the
> > capacity of the internal degrees of freedom of the system
> to dissipate
> > the gradient".
> >
> >
> > Is that formal enough? or, does the statement need to be
> mathematized?
> >
> > -Steve
> >
> > ________________________________________
> > Stephen.Guerin at Redfish.com
> > www.Redfish.com
> > 624 Agua Fria Street, Santa Fe, NM 87501
> > mobile: [phone]
> > office: Santa Fe, NM [phone] / London, UK [phone]
> >
> >
> > ============================================================
> > FRIAM Applied Complexity Group listserv Meets Fridays
> 9a-11:30 at cafe
> > at St. John's College lectures, archives, unsubscribe, maps at
> > http://www.friam.org
> >
> >
> >
> >  
>
> ============================================================
> FRIAM Applied Complexity Group listserv
> Meets Fridays 9a-11:30 at cafe at St. John's College
> lectures, archives, unsubscribe, maps at http://www.friam.org
>
>

[Stephen Guerin]

Phil,

> Not sure if it fits, but the type of complex systems I first
> carefully studied were natural air currents.  

Yes, the emergence of convective cells, esp Rayleigh-B?nard convection, is an
oft-cited example in Complexity:
http://en.wikipedia.org/wiki/Convection

> I think this behavior probably fits your model somehow, but I don't see the
> degrees of freedom or capacities you refer to as the gateway to relieving any
gradient.  

You can look at the degrees of freedom of the elements/agents in the system. In
this case, it would be the air molecules. Given a small gradient below a
critical value, the molecules are able to randomly collide with one another and
transfer the energy along the gradient. In the absence of a gradient, the air
molecules are unorganized and have maximum degrees of freedom. The system is
symmetric and at maximum entropy. ie, given the position of one air molecule, an
observer has no information about the position of another air particle and no
work can be extracted from the system.

As you move the system away from equilibrium by applying an energy gradient, the
air particles will initially dissipate the potential primarily via conduction (a
heat process). Heat can be defined as the unconstrained transfer of energy.
Here, i would interpret unconstrained as the air particle randomly transfering
into their six degrees of freedom the energy from the gradient. Random
collisions obeying conservation of momentum will propagate the energy along the
gradient setting up a flow process.

As the systems is moved further from equilibrium, it will cross a critical
threshold where the ability of the system to dissipate the potential via a
purely heat process will be insufficient. The motion of the air particles will
become coordinated into convective cells and the majority of the dissipation
will happen via mass transfer instead of conduction. Coordination implies that
the state of one air molecule is constrained by the state of another air
molecule. Emergence of constraint is the loss of degrees of freedom at the micro
level. Air molecules lose degrees of freedom as the system becomes organized via
convection.

In our language, conduction is a heat process (the unconstrained transfer of
energy). Convection is a work process (the constrained transfer of energy).

In other systems like the ant foraging ABM model, we're trying to generalize the
notions of "work" and "heat" beyond traditional mechanical processes. we've said
that work is performed on the agents at the micro level as the system becomes
complex and moves toward an organized state. For example, ants are informed by
the pheromone field; work is peformed on them as they lose degrees of freedom in
their movement and follow the gradient.

Ultimately, I'm claiming, unformally at this point, that complex systems are a
method for converting heat to work.

-Stephen
 

> -----Original Message-----
> From: Phil Henshaw [mailto:sy at synapse9.com]
> Sent: Saturday, July 22, 2006 2:29 PM
> To: 'The Friday Morning Applied Complexity Coffee Group'
> Subject: Re: [FRIAM] formalization of Complexity (was
> Dynamics of ComplexSystems by Yaneer Bar-Yam)
>
> Steven,
>
> Not sure if it fits, but the type of complex systems I first
> carefully studied were natural air currents.  
>
> There's a clear energy gradient involved when sunlight
> provides heat at the bottom of a column of air and buoyancy
> drives the development of intricate motions.  What I noticed
> is that the paths of motion evolve individually by growth
> processes.  Some small perturbation at an instability results
> in a positively reinforced development of movements, that
> gives the air a system of solving the problem of getting out of its
> own way, to release the gradient.   From observation, it looks like
> there are some delays in the right disturbance occurring, perhaps.
> Individual currents rising from a floor can develop in what
> appears to be erratic and lazy fashion.
>
> I think this behavior probably fits your model somehow, but I
> don't see the degrees of freedom or capacities you refer to
> as the gateway to
> relieving any gradient.  
>
> Make any sense?
>
>
>
> >
> >
> >  
> > >  Yet when I ask for a formal treatment, I get no answer.
> >
> > I very much like Hubler's deceptively simple definition of
> complexity:
> > "A complex systems is a system with large throughput of Energy,
> > Information, Force, .... through a well designed boundary."
> >
> > His notes from the SFI CSSS school with this definition are
> > here: http://www.how-why.com/ucs2002/tutorial/
> >
> >
> > As a restatement of the same ideas that formalizes what
> "large" means,
> > I would
> > offer:
> > "complexity emerges when a gradient acting on a system
> exceeds the
> > capacity of the internal degrees of freedom of the system
> to dissipate
> > the gradient".
> >
> >
> > Is that formal enough? or, does the statement need to be
> mathematized?
> >
> > -Steve
> >
> > ________________________________________
> > Stephen.Guerin at Redfish.com
> > www.Redfish.com
> > 624 Agua Fria Street, Santa Fe, NM 87501
> > mobile: [phone]
> > office: Santa Fe, NM [phone] / London, UK [phone]
> >
> >
> > ============================================================
> > FRIAM Applied Complexity Group listserv Meets Fridays
> 9a-11:30 at cafe
> > at St. John's College lectures, archives, unsubscribe, maps at
> > http://www.friam.org
> >
> >
>
>
>
> ============================================================
> FRIAM Applied Complexity Group listserv
> Meets Fridays 9a-11:30 at cafe at St. John's College
> lectures, archives, unsubscribe, maps at http://www.friam.org
>
>

[Robert Holmes]

On 7/23/06, Stephen Guerin <stephen.guerin at redfish.com> wrote:
>
> ...
>
In other systems like the ant foraging ABM model, we're trying to generalize

> the
> notions of "work" and "heat" beyond traditional mechanical processes.
> we've said
> that work is performed on the agents at the micro level as the system
> becomes
> complex and moves toward an organized state. For example, ants are
> informed by
> the pheromone field; work is peformed on them as they lose degrees of
> freedom in
> their movement and follow the gradient.
>
> Ultimately, I'm claiming, unformally at this point, that complex systems
> are a
> method for converting heat to work.
>
> -Stephen

I think you're going to end up in an irreconcilable paradox here.  Take the
case of conservation laws: if you want to use conventional statistical
mechanics and thermodynamics, then your 'new' energy (whatever you want to
call it) is going to have some conservation law attached to it. But
information flow between agents is not conserved. For example, the
information you extract from this specific email is not in any way affected
by the number of people reading it.

Sure, I can impose conservation laws on (say) information flows because I am
building the model and can impose any rule structure on it I like. But that
would seem (IMHO) to represent too great a dislocation from reality for any
ABM derived from that assumption to be particularly realistic.

Alternatively, I could accept that something like information is not
conserved. But if I do this then I can't treat information as an analogue of
energy and I don't get to use all those well-established stat mech and
thermodynamics laws.

Robert
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[Carlos Gershenson]

>
> The FRIAM list has been through several very philosophical
> conversations over 3-4 weeks, all purporting to be "complex".  Yet
> when I ask for a formal treatment, I get no answer.

The problem is that there are too many formal treatments of  
complexity...

For a good introduction, see Murray Gell-Mann's
http://www.santafe.edu/~mgm/complexity.html

Best regards,

     Carlos Gershenson...
     Centrum Leo Apostel, Vrije Universiteit Brussel
     Krijgskundestraat 33. B-1160 Brussels, Belgium
     http://homepages.vub.ac.be/~cgershen/

   ?Tendencies tend to change...?

[Jochen Fromm-3]

The problem is not that there are too few or too many
formal treatments of complexity. IMHO formal treatments of
"complexity", "self-organization" or "emergence" are not a solution.
The lack of formal treatments is not a problem, it indicates
that these terms are buzzwords. Buzzwords have their assets
and drawbacks, they are powerful tools to get funding, to
write successful project proposals, to get things published,
to capture attention, to impress people, etc., but they
should be treated with care (because they might lead to
mathematical quagmire, confusion, misunderstandings,
illusions, contradictions, schisms in communities, etc.)
http://www.vs.uni-kassel.de/systems/index.php/Buzzword 

-J.

-----Original Message-----
From: Carlos Gershenson
Sent: Monday, July 24, 2006 5:56 PM
To: The Friday Morning Applied Complexity Coffee Group
Subject: Re: [FRIAM] Dynamics of Complex Systems by Yaneer Bar-Yam

The problem is that there are too many formal treatments of  
complexity...

[Phil Henshaw-2]

As generalities go, I would agree that lots of emergent things do fit
the general idea of converting heat to work, including convection.
Convection actually is a direct conversion of disorganized to organized
molecular motion in that sense.  

I'm still not quite clear that there are degrees of freedom with
capacities that are driven by a gradient.   When you watch air currents
develop the dominant impression is of an perfect stillness that
gracefully takes on an intricately layered winding motion, becoming a
buoyant torpedo-like cell in which a column rises in the center and
splits at the nose to counter flow down the outside.  They're really
beautiful in their detail, spontaneity and variety.  

The region of molecules around where the seed of the cell's growth
devlops is changed enormously, but why is it implied that the
environment of any individual molecule is any different than before?
A Wikipedia entry on the speed of sound tells me the mean free velocity
of air molecules is about 1.4 times the speed of sound.  The speed of
air currents is almost nothing by comparison.


Phil Henshaw                       ????.?? ? `?.????
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
680 Ft. Washington Ave
NY NY 10040                      
tel: [phone]                
e-mail: pfh at synapse9.com          
explorations: www.synapse9.com    

> -----Original Message-----
> From: Stephen Guerin [mailto:stephen.guerin at redfish.com]
> Sent: Sunday, July 23, 2006 7:34 PM
> To: sy at synapse9.com; 'The Friday Morning Applied Complexity
> Coffee Group'
> Subject: RE: [FRIAM] formalization of Complexity
>
>
> Phil,
>
> > Not sure if it fits, but the type of complex systems I first
> > carefully studied were natural air currents.  
>
> Yes, the emergence of convective cells, esp Rayleigh-B?nard
> convection, is an oft-cited example in Complexity:
> http://en.wikipedia.org/wiki/Convection
>
> > I think this behavior probably fits your model somehow, but I don't
> > see the degrees of freedom or capacities you refer to as
> the gateway
> > to relieving any
> gradient.  
>
> You can look at the degrees of freedom of the elements/agents
> in the system. In this case, it would be the air molecules.
> Given a small gradient below a critical value, the molecules
> are able to randomly collide with one another and transfer
> the energy along the gradient. In the absence of a gradient,
> the air molecules are unorganized and have maximum degrees of
> freedom. The system is symmetric and at maximum entropy. ie,
> given the position of one air molecule, an observer has no
> information about the position of another air particle and no
> work can be extracted from the system.
>
> As you move the system away from equilibrium by applying an
> energy gradient, the air particles will initially dissipate
> the potential primarily via conduction (a heat process). Heat
> can be defined as the unconstrained transfer of energy. Here,
> i would interpret unconstrained as the air particle randomly
> transfering into their six degrees of freedom the energy from
> the gradient. Random collisions obeying conservation of
> momentum will propagate the energy along the gradient setting
> up a flow process.
>
> As the systems is moved further from equilibrium, it will
> cross a critical threshold where the ability of the system to
> dissipate the potential via a purely heat process will be
> insufficient. The motion of the air particles will become
> coordinated into convective cells and the majority of the
> dissipation will happen via mass transfer instead of
> conduction. Coordination implies that the state of one air
> molecule is constrained by the state of another air molecule.
> Emergence of constraint is the loss of degrees of freedom at
> the micro level. Air molecules lose degrees of freedom as the
> system becomes organized via convection.
>
> In our language, conduction is a heat process (the
> unconstrained transfer of energy). Convection is a work
> process (the constrained transfer of energy).
>
> In other systems like the ant foraging ABM model, we're
> trying to generalize the notions of "work" and "heat" beyond
> traditional mechanical processes. we've said that work is
> performed on the agents at the micro level as the system
> becomes complex and moves toward an organized state. For
> example, ants are informed by the pheromone field; work is
> peformed on them as they lose degrees of freedom in their
> movement and follow the gradient.
>
> Ultimately, I'm claiming, unformally at this point, that
> complex systems are a method for converting heat to work.
>
> -Stephen
>  
> > -----Original Message-----
> > From: Phil Henshaw [mailto:sy at synapse9.com]
> > Sent: Saturday, July 22, 2006 2:29 PM
> > To: 'The Friday Morning Applied Complexity Coffee Group'
> > Subject: Re: [FRIAM] formalization of Complexity (was
> > Dynamics of ComplexSystems by Yaneer Bar-Yam)
> >
> > Steven,
> >
> > Not sure if it fits, but the type of complex systems I first
> > carefully studied were natural air currents.  
> >
> > There's a clear energy gradient involved when sunlight
> > provides heat at the bottom of a column of air and buoyancy
> > drives the development of intricate motions.  What I noticed
> > is that the paths of motion evolve individually by growth
> > processes.  Some small perturbation at an instability results
> > in a positively reinforced development of movements, that
> > gives the air a system of solving the problem of getting out of its
> > own way, to release the gradient.   From observation, it looks like
> > there are some delays in the right disturbance occurring, perhaps.
> > Individual currents rising from a floor can develop in what
> > appears to be erratic and lazy fashion.
> >
> > I think this behavior probably fits your model somehow, but I
> > don't see the degrees of freedom or capacities you refer to
> > as the gateway to
> > relieving any gradient.  
> >
> > Make any sense?
> >
> >
> >
> > >
> > >
> > >  
> > > >  Yet when I ask for a formal treatment, I get no answer.
> > >
> > > I very much like Hubler's deceptively simple definition of
> > complexity:
> > > "A complex systems is a system with large throughput of Energy,
> > > Information, Force, .... through a well designed boundary."
> > >
> > > His notes from the SFI CSSS school with this definition are
> > > here: http://www.how-why.com/ucs2002/tutorial/
> > >
> > >
> > > As a restatement of the same ideas that formalizes what
> > "large" means,
> > > I would
> > > offer:
> > > "complexity emerges when a gradient acting on a system
> > exceeds the
> > > capacity of the internal degrees of freedom of the system
> > to dissipate
> > > the gradient".
> > >
> > >
> > > Is that formal enough? or, does the statement need to be
> > mathematized?
> > >
> > > -Steve
> > >
> > > ________________________________________
> > > Stephen.Guerin at Redfish.com
> > > www.Redfish.com
> > > 624 Agua Fria Street, Santa Fe, NM 87501
> > > mobile: [phone]
> > > office: Santa Fe, NM [phone] / London, UK +44 (0)
> 20 7993 4769
> > >
> > >
> > > ============================================================
> > > FRIAM Applied Complexity Group listserv Meets Fridays
> > 9a-11:30 at cafe
> > > at St. John's College lectures, archives, unsubscribe, maps at
> > > http://www.friam.org
> > >
> > >
> >
> >
> >
> > ============================================================
> > FRIAM Applied Complexity Group listserv
> > Meets Fridays 9a-11:30 at cafe at St. John's College
> > lectures, archives, unsubscribe, maps at http://www.friam.org
> >
> >
>
>