What Math Can Tell Us About Technology's Spread Through Cities

Sociologists have been studying social networks for some 50 years, trying to understand how groups of people connect to each other and how new ideas and tools travel between them. Our understanding of these networks is rapidly evolving, though. "Now," says Nick McCullen, a researcher based in the U.K., "physicists and mathematicians have been getting in on the game with their computer models." And the potential implications for some of our largest physical networks of people – cities – are pretty intriguing.

McCullen and a team of colleagues have been trying to mathematically model how energy-efficient technology is diffused through a community, in the hopes that city policy-makers might one day be able to use this sophisticated math to figure out how to get you (and your friends, and your friends’ friends) to install solar panels on your roof or to retrofit that drafty attic.