Complexity

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Complexity
Sorin Solomon, Racah Institute of Physics HUJ
Israel Complex Multi-Agent Systems Division, ISI
TurinLagrange Interdisciplinary Lab for
Excellence In Complexity
MORE IS DIFFERENT (Anderson 72)(more is more
than more) Complex Macroscopic properties may
be the collective effect of many simple
microscopic components (and independent on
their details)

• Phil Anderson Real world is controlled
• by the exceptional, not the mean
• by the catastrophe, not the steady drip
• by the very rich, not the middle class.
  we need to free ourselves from average
  thinking.

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Semiotics and Ontology
SocialScience
Biology
WordsMeaning
ChemicalsCells
IndividualsSociety
Phase Transitions, clusters, scaling
Computers
BusinessAdministration
BitsInformation items
AtomsDrops
CustomerMarket
Economicsand Finance
Statistical Physics
Cognition
NeuronsBrain
TradersHerds
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Instead of temperature Exchange rate/interest
rate Value At Risk / liquid funds Equity Price /
Dividends Equity Price / fundamental
value Political Activity Education
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Systems, Organisms health,
perception self-non-self recognition
Cells
chemotaxis, metabolism
DNA chains, proteins reproduction,evolution,syn
thesis
Chemicals
almost free particles
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The Multi-Agent Complex Systems Paradigm MICRO -
the relevant microscopic degrees of
freedom         INTER - their fundamental
interactions         MACRO - the macroscopic
emerging collective objects

• Intrinsically (3x) interdisciplinary
• MICRO belongs to one science
• MACRO to another science
• Mechanisms statistical mechanics (?)
  phase transitions, scale
  invariance,

The challenge
transcend traditional disciplinary research
Complexity Research More than a juxtaposition
of expertises a new grammar with new
interrogative forms allowing
the formulation of new questions. Grow a new
generation of bi- or multi-lingual scientists.
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Microscopic Links, Macroscopic NetworksMICRO
Nodes, connections INTERACTIONS - Local changes
(node / link (dis-) appearance)MACRO- Global
connectivity, percolation, topology
New generation of network studiesInstead of
study generic properties that are not specific to
any particular system, Study specific macroscopic
collective properties implied by specific
elementary interactions..
Gene activation
WWW linking
site
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  - Microscopic Immune Cells and Macroscopic
HealthMICRO  - Cells, Enzimes, Antigens,
Antibodies          INTER -producing,
destroying, changing state of cells/enzymesMACRO
- immunity, health, infection, sickness,
inflamation.
Losing All Battles and Wining the War HIV time
hierarchy U Hershberg, Y Louzoun, H Atlan and
S Solomon Physica A 289 (1-2) (2001) pp.178-190
Antigen-receptor degeneracy and immunological
paradigms Irun R. Cohen,, Uri Hershberg, Sorin
SolomonMolecular Immunology 40 (2004) 993996
Acute Phase
T-cells
HIV
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- Microscopic seeds and Macroscopic Oases   
MICRO individual plants     INTER growth,
water fixation, MACRO bushes, vegetation
patches N.M. Shnerb, P. Sarah, H. Lavee, and S.
Solomon Reactive glass and vegetation patterns
Phys. Rev. Lett. 90, 38101 (2003)
Semi-arid patchy
Desertuniform
Mediterranean uniform
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- Microscopic Investors and Macroscopic
CrashesMICRO - Investors, individual
capital ,shares         INTER - sell/buy orders,
gain/loss          MACRO - social wealth
distribution, market price fluctuations
(cycles, crushes, booms, stabilization by
noise)
Levy, Solomon and Levy's Microscopic Simulation
of Financial Markets points us towards the
future of financial economics. If we restrict
ourselves to models which can be solved
analytically, we will be modeling for our mutual
entertainment, not to maximize explanatory or
predictive power."HARRY M. MARKOWITZ, Nobel
Laureate in Economics
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Realistic macroscopic simulations require a new
causal framework discrete / delayed/ conditional
/ nested causality
instead of the usual Markov
infinitesimal one
New mathematical concept Markov Webs
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Realistic Continuous Time Simulation Platform
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- Microscopic Draws and Macroscopic Drawings
MICRO - local line / motion features, mental
states, mental eventsINTER - line breaks and
mind events vs line/mind inertia.MACRO - drawing
shapes, emergence of meaning Emergence of
Representation in Drawing The Relation Between
Kinematic and Referential Aspects E Adi-Japha, I
Levin and S. Solomon, Cognitive Development 13
(1998) 25
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-Microscopic Concepts and Macroscopic Ideas MICRO
- concepts, connections between conceptsINTER
- creating/deleting connections between
conceptsMACRO Novel products, creative ideas,
real-life problem solving
Creative Sparks, J Goldenberg, D Mazursky, and S
SolomonScience 285 1495-1496, 1999 Templates
of original innovation Projecting original
incremental innovations from intrinsic
information Goldenberg J. Mazursky D. Solomon
S., (1999) Technological Forecasting and Social
Change, May, Vol. 61/1 P. 1-12.
Communication at the speed of sound
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Individual Losers and Collective Winners MICRO
individuals with arbitrary high death rateINTER
arbitrary low birth rate arbitrary low density
of catalisersMACRO always resilient collective
patches (THEOREM) The importance of being
discrete Life always wins on the surface N M.
Shnerb, Y Louzoun, E Bettelheim, and S Solomon
Proc. Natl. Acad. Sci. USA, 97/ 19,
10322-10324, Sep 12, 2000 http//xxx.lanl.gov/abs
/adap-org/9912005 Proliferation and Competition
in Discrete Biological Systems Y Louzoun S
Solomon, H Atlan and I R. Cohend Bulletin of
Mathematical Biology Volume 65, Issue 3 , May
2003, P 375-396
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Economy (89-92) vs. EDUCATION (88) note
complete correspondence to educationAFTER (92)
but NOT BEFORE(89) liberalization
Nowak
1989
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Fractal Wealth Distribution Scaling Power laws
No one however, has yet exhibited a stable social
order, ancient or modern, which has not followed
the Pareto pattern Davis Cowles Commission for
Research in Economics

Paretos curve

great generalizations

of human knowledge.

Snyder 1939
WALMART
GATES
Buffet
ALLEN
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Dell
Zipf
plot of the
wealths
of the investors in the Forbes 400 of 2003 vs.
their ranks. The corresponding model results are
shown in the in
set.
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Distribution of individual wealth
(by MACS Prediction)
Distribution of global financial fluctuations
Levy
Social equity is good for the financial stability!
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- Microscopic Customers and Macroscopic
Sales      MICRO Customers, products / ideas /
information     INTER purchase, inform, learn,
hear-sayMACRO global trends, waves of sales
(e.g. Tamaguchi), hits, flops,
market fluctuations, anomalous diffusion
Percolation transition From non-sales
at all to a lot of salesSocial Percolators and
Self-Organized Criticality Gerard Weisbuch ,
Sorin Solomon in Economics with heterogeneous
interacting agents, page 43. eds A.Kirman and
J.B. Zimmermann, Lecture Notes in Economics and
Mathematics, Springer, 2001
Sales
Potential buyers
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60
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fractal space distribution
Prediction of campaign success (15/17)
Goldenberg
Air-view of a sub-urban neighborhood crosses on
the roofs indicate air-conditioner purchase
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Sales extrapolation formula vs microscopic
representation
CAR SALES in USA 1895-1930
Extrapolation

• New Generation of ModelsTake into account
  negative reaction to the propagation
• Negative word-of-mouth unsatisfied customers
  influence their contacts in non-buying
  anti-percolation.
• anti-viruses propagating on almost the same
  network role of additional links antivirus
  arrives first.
• Timing of transmission not all contacts are
  always active

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Conclusions
Complexity
No Doctrina
May be Unifying Language
Simple Microscopic Agents Dynamics
Macroscopic Complexity