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Our world is becoming increasingly citified. Of more than 9 billion humans projected to live on earth by 2050, an estimated 70% of them will be urban dwellers. But what will their cities look like? A dense, well-planned urban center can run like a well-oiled machine, cutting down on waste, reducing vehicle travel, and helping people stay connected. But cities can also lead to urban sprawl, and can reinforce inequalities, leaving poor and minority residents isolated even in the midst of a metropolis.
How do we design more efficient cities to accommodate an exploding population? What evidence do we have about the effects of close-quarters living on our social and economic structure? What will cities of the future look like, and what will it be like to live in one? Join a live chat, broadcast from the 2014 AAAS conference in Chicago, with experts who have been exploring these questions from the perspectives of engineering and social science.
See more of our coverage from AAAS 2014 .