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Lecture 11. Echoing the emergence. Santa Fe Institute. Formed in 1985 Think tank to deal with complexity Scientists from all areas including physics, chemistry, biology, computer science, economics, ecology, sociology, history, etc . http://www.santafe.edu. The Flow. Dynamical systems
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Lecture 11 Echoing the emergence
Santa Fe Institute • Formed in 1985 • Think tank to deal with complexity • Scientists from all areas including physics, chemistry, biology, computer science, economics, ecology, sociology, history, etc. • http://www.santafe.edu
The Flow • Dynamical systems • We find ourselves among ever-changing systems • There is an intractable number of branches • Feedback • Systems change and develop by receiving feedback from the environment and responding to environment. Thus systems are inextricable parts of the environment • Self-reference • The systems around us are heavily recursive, self-bootstrapping • Co-evolution • There is no stand alone evolution, everything is co-evolving. • Everything is dependent and influences everything else.
Cybernetics • Norbert Wiener • Trying to understand how control & communication worked • Greek kybernetes (steersman) (Web of life pp.. 97) • We are but whirlpools in a river of ever-flowing water • Self-regulation • We are not stuff that abides, but patterns that perpetuate themselves Situation Assessment Action Impact on environment
Ilya Prigogine • Second law of thermodynamics • In closed system, the amount of entropy in a given system does not decrease • Entropy means disorder • Living organisms and equilibrium • Living beings are in order, away from equilibrium • Open thermodynamical systems • Nonlinear equations • Self-Organization Equilibrium (ice) Order (edge of chaos) Chaos (gas)
Prisoners’ Dilemma - Two thieves are captured and both promised life if they would tell on each other. The problem is that ideally, they should simply just not tell on each other. But one of they think 'What if the other guy tells on me?' Then I will be in jail, and he will be spared. So they both defect, i.e. tell on each other and loose. - Iterative nature of biological games
Seven basic elements of CAS • Aggregation • Economy and markets • Body and nervous, immune, endocrine system • World economy and country economies • Emergence as a result of interactions • whole > sum of the parts • higher level of organization • meta agents
Seven basic elements of CAS • Tagging (mechanism) • Identification of alike agents • Grouping • Attribute • contracts between firms • form of adaptation - delegation • Divisions in a firm Equities, Fixed Income, etc. • collaboration, formation of aggregate and diversification via tagging
Seven basic elements of CAS • Nonlinearity (property) • aggregation & tagging • threshold of emergence (H >sum(P)) • predator/prey interaction • One of the standard example of nonlinear dynamical model is predator/prey interaction. Observe that increases in either population increase the likelihood of a contact. Let Predator(t), and Prey(t) be number of predators and prey at some time t, and let c be the constant that reflects efficiency of a predator. We can calculate the number of interactions per unit of time as c*Predator(t)*Prey(t). That is, with c = 0.5, Predator(t) = 2 and Prey(t) = 10, we would have 10 encounters. Now, let us double each population so that Predator(t) = 4 and Prey(t) = 20, then we will have 40 encounters. • nonlinearity is a result of a product instead of a sum
Seven basic elements of CAS • Flow (property) • nonlinearity induces flow • multiplier effect • feedback and cycles = Dead = Alive
Seven basic elements of CAS • Diversity (property) • arise from exploration of multitude of possibilities (local adaptations) • firms enter and leave market • mimicry
Seven basic elements of CAS • Internal models (mechanism) • ‘anticipation’ • survival of the fittest • subconscious mode
Seven basic elements of CAS • Building blocks (mechanism) • decomposition • quark, nucleon, atom, molecule, organelle, cell • generation of internal models
Eworld Resources <RESOURCE CLASS=edu.nyu.sejava.iskold.eworld.HomogeneousResource> <PROPERTY NAME=Quantity VALUE=25> <PROPERTY NAME=Base VALUE=a> <PROPERTY NAME=Renewable VALUE=true> </RESOURCE>
Eworld Resources <RESOURCE CLASS=edu.nyu.sejava.iskold.eworld.HomogeneousResource <RBASE> <PROPERTY NAME=Quantity VALUE=2> <PROPERTY NAME=Base VALUE=a> </RBASE> <RBASE> <PROPERTY NAME=Quantity VALUE=2> <PROPERTY NAME=Base VALUE=t> </RBASE> <PROPERTY NAME=Renewable VALUE=false> </RESOURCE>
Entity’s Genome - Reservoir (place where excess resources are stored) - 3 PhenoGenes (externally visible) - OffenseGene - Defense Gene - Mating Gene - 3 Rule Genes (internal only) - CombatConditionGene - TradeConditionGene - MatingConditionGene - Resource collection gene - Trading resource base
Entity Generators <GENERATOR CLASS=edu.nyu.sejava.iskold.eworld.BasicRandomEntityGenerator> <PROPERTY NAME=Quantity VALUE=25> </RESOURCE> <GENERATOR CLASS=edu.nyu.sejava.iskold.eworld.BasicConstrainedEntityGenerator> <PROPERTY NAME=Quantity VALUE=25> <PROPERTY NAME=OffenseGeneLength VALUE=5> <PROPERTY NAME=OffenseGeneBases VALUE=AT> </RESOURCE>
Entity near Resource - Is this resource empty? - Does my Resource Collection Gene allow me to pick up next base from this resource? NOPE, NO MATCH C A T G NEXT BASE IN SOME RESOURCE
Cloning - Does my Reservoir contain enough bases to clone myself? Cloning threshold is at least 1 Offense ACG Defense AAA Mating CGT Combat Condition AAGT Trade Condition GGG Mating Condition CG Resource collection AG Trading resource A RESERVOIR CONTAINS TWICE THE GENOME 16 A 4 T 6 C 16 G
Mortality - Every round kill entities at random - The longer entity lives the higher its chance of dying
Some book references Complexity, by M. Mitchell Waldrop At Home in the Universe, by Stuart Kauffman Web Of Life, by Frijof Capra The Blind Watchmaker, by Richard Dawkins