The physical modelling of society

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The physical modelling of society
Philip Ball
Nature 4-6 Crinan St London N1 9XW p.ball_at_nature.c
om
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Thomas Hobbes (1588-1679)
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The first social physicists
Auguste Comte (1798-1857)
Pierre-Simon Laplace (1749-1827)
John Graunt (1620-74)
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The gaussian distribution
Probability of variable h
Variable h
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The first statistical physicists
Maxwell distribution
James Clerk Maxwell (1831-1879)
Ludwig Boltzmann (1844-1906)
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there is an unbridgeable gap between the
behaviour of subatomic particles and those of
the human beings who constitute the objects of
study of social science... aside from pure
physical reflexes, human behaviour cannot be
understood without the concept of volitionthe
unpredictable capacity to change our minds up to
the very last moment. By way of contrast, the
elements of nature behave as they do for
reasons of which we know only one thing the
particles of physics do not choose to behave as
they do. Robert Heilbroner
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Density
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Critical transition
First-order transition
Magnetization
Density
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The Ising model
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The critical point
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Critical fluctuations
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Self-organized criticality
Probability of avalanche of that size
Log (probability)
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Economic fluctuations
SP500
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Traffic states
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Alliance formation
B
A
C
Alliance 2 DEC Hewlett-Packard Apollo Intergraph S
GI
Alliance 1 Sun ATT Prime IBM
UNIX International (IBM)
Open Software Foundation (-IBM)
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Firm growth rates
Relative probability
No change
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Firm size distribution
Number of firms
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Firm turnover
Size of largest firm
Number of firms
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Experimental firm size distribution
Frequency of firms of that size
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Experimental firm growth rates
Frequency
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Typical firm history
Firm size
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Social forces and marriage
Proportion of adult population married
Density
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Marriage as a critical phenomenon
Strength of social attitudes
Economic incentive to stay married
Temperature
Pressure