Geoffrey West is a British theoretical physicist, former president and distinguished professor of the Santa Fe Institute. He is one of the leading scientists working on a scientific model of cities. Among other things his work states that with the doubling of a city's size, services per capita will generally increase by 15%.

Physicist Geoffrey West has found that simple, mathematical laws govern the properties of cities -- that wealth, crime rate, walking speed and many other aspects of a city can be deduced from a single number: the city's population. In this mind-bending talk from TEDGlobal he shows how it works and how similar laws hold for organisms and corporations.

看看这上面视频的最后三分钟（http://youtu.be/XyCY6mjWOPc?t=13m58s），就知道AAPL、MSFT、GOOG等成熟公司的股票都没有什么投资的大赚头了。