The high-density future of cities around the world, rendered crisply in photo-realistic drawings and computer models, will be one of massive skyscrapers performing wonderful tricks. They'll grow food, they'll generate renewable energy, they'll spin and twirl to cater to our whims and give us a shady spot beneath a tree, thousands of feet in the air, where we can sit quietly and ponder the urban condition evolving around us, above and below.
This is the future as imagined by architects and designers, who have dreamed up fantastic new ideas for housing and feeding and keeping sane the billions of people expected to concentrate in urban centers all over the planet.
Their designs, available widely online through design competitions and architecture websites, offer an almost tangible vision of the city of tomorrow. One example is a design recently named to the shortlist for the 2014 World Architecture Festival awards. It's a split tower design for Hong Kong that features floors for housing, commercial use and offices, as well as fish farms, solar power stations, rooftop rice paddies, and vegetation growing down its façades. Projects like this offer smart, sometimes ingenious ideas about how we can and should live in buildings and cities. And that's what makes it so disappointing to realize they will never be built.