a physicist solves the city

NYTimes | “We spend all this time thinking about cities in terms of their local details, their restaurants and museums and weather,” West says. “I had this hunch that there was something more, that every city was also shaped by a set of hidden laws.”

And so West set out to solve the City. As he points out, this is an intellectual problem with immense practical implications. Urban population growth is the great theme of modern life, one that’s unfolding all across the world, from the factory boomtowns of Southern China to the sprawling favelas of Rio de Janeiro. As a result, for the first time in history, the majority of human beings live in urban areas. (The numbers of city dwellers are far higher in developed countries — the United States, for instance, is 82 percent urbanized.) Furthermore, the pace of urbanization is accelerating as people all over the world flee the countryside and flock to the crowded street.

This relentless urban growth has led to a renewed interest in cities in academia and in government. In February 2009, President Obama established the first White House Office of Urban Affairs, which has been told to develop a “policy agenda for urban America.” Meanwhile, new perspectives have come to the field of urban studies. Macro­economists, for instance, have focused on the role of cities in driving gross domestic product and improving living standards, while psychologists have investigated the impact of city life on self-control and short-term memory. Even architects are moving into the area: Rem Koolhaas, for one, has argued that architects have become so obsessed with pretty buildings that they’ve neglected the vital spaces between them.

But West wasn’t satisfied with any of these approaches. He didn’t want to be constrained by the old methods of social science, and he had little patience for the unconstrained speculations of architects. (West considers urban theory to be a field without principles, comparing it to physics before Kepler pioneered the laws of planetary motion in the 17th century.) Instead, West wanted to begin with a blank page, to study cities as if they had never been studied before. He was tired of urban theory — he wanted to invent urban science.

For West, this first meant trying to gather as much urban data as possible. Along with Luis Bettencourt, another theoretical physicist who had abandoned conventional physics, and a team of disparate researchers, West began scouring libraries and government Web sites for relevant statistics. The scientists downloaded huge files from the Census Bureau, learned about the intricacies of German infrastructure and bought a thick and expensive almanac featuring the provincial cities of China. (Unfortunately, the book was in Mandarin.) They looked at a dizzying array of variables, from the total amount of electrical wire in Frankfurt to the number of college graduates in Boise. They amassed stats on gas stations and personal income, flu outbreaks and homicides, coffee shops and the walking speed of pedestrians.

After two years of analysis, West and Bettencourt discovered that all of these urban variables could be described by a few exquisitely simple equations. For example, if they know the population of a metropolitan area in a given country, they can estimate, with approximately 85 percent accuracy, its average income and the dimensions of its sewer system. These are the laws, they say, that automatically emerge whenever people “agglomerate,” cramming themselves into apartment buildings and subway cars. It doesn’t matter if the place is Manhattan or Manhattan, Kan.: the urban patterns remain the same. West isn’t shy about describing the magnitude of this accomplishment. “What we found are the constants that describe every city,” he says. “I can take these laws and make precise predictions about the number of violent crimes and the surface area of roads in a city in Japan with 200,000 people. I don’t know anything about this city or even where it is or its history, but I can tell you all about it. And the reason I can do that is because every city is really the same.” After a pause, as if reflecting on his hyperbole, West adds: “Look, we all know that every city is unique. That’s all we talk about when we talk about cities, those things that make New York different from L.A., or Tokyo different from Albuquerque. But focusing on those differences misses the point. Sure, there are differences, but different from what? We’ve found the what.” Fist tap ProfGeo.