Cities have long been likened to organisms, ant colonies, and river networks. But these and other analogies fail to capture the essence of how cities really function.
New research by Santa Fe Institute Professor Luis Bettencourt suggests a city is something new in nature – a sort of social reactor that is part star and part network, he says.
"It’s an entirely new kind of complex system that we humans have created," he says. "We have intuitively invented the best way to create vast social networks embedded in space and time, and keep them growing and evolving without having to stop. When that is possible, a social species can sustain ways of being incredibly inventive and productive."
In a cover paper appearing this week in the journal Science, Bettencourt derives a series of mathematical formulas that describe how cities' properties vary in relation to their population sizes, and then posits a novel unified, quantitative framework for understanding how cities function and grow.
Read the paper in Science (June 20, 2013)