科学美国人60秒:Is There a Formula for Better Cities?

For the first time, more people now live in cities than the countryside—a trend of increasing urbanization that is expected to continue.

Based on data from thousands of cities on everything from number of patents generated to road lengths, researchers at the Santa Fe Institute have uncovered the math by which human settlements grow from town to city to metropolis. So, for example, a social network between people within the city grows in a mathematical relationship with the increase in the size and quality of infrastructure, such as roads, power lines and the like.

In essence, the bigger the city, the greater the opportunities—but negatives or costs also rise, such as crime or traffic congestion. To optimize urban function, the research suggests following policies that allow for a denser web of human connections while minimizing the costs imposed by transportation and energy use.

The real test of these ideas will be how they stack up against data from the burgeoning cities of the developing world. China alone has added hundreds of cities with millions of people in the last few decades—and wants to add yet more. To do it right, city planners will need to brush up on their math.

—David Biello