Source: http://www.wired.com/2015/03/plan-build-...

About 250 skyscrapers are slated to redraw London’s skyline in the near future—each with its own dark imprint on the streets below. So architects at the firm NBBJ in London decided to see if they could come up with an entirely shadowless building. They used computer modeling to design a pair of buildings, one of which works like a gigantic, curved mirror. The glass surface of the northernmost building reflects light down into the shadow cast by its southern partner. And the carefully defined curve of that glass allows the reflected light to follow the shadow throughout the day. Note that the reflected light is diffuse—not a focused death ray that could fry an egg or burn tourists. “The relationship between the sun and shadow is the relationship between the two buildings,” says Christian Coop, NBBJ’s design director.