Stroll into the lobby of the Contemporary Arts Center at Sixth and Walnut streets downtown, and you are instantly immersed in another world, one that is buoyant and filled with dreamy light filtering through intersecting spaces. In front of you is what architect Zaha Hadid called the “urban carpet.” It flows from the concrete sidewalk outside, onto the floor of the glass-enclosed lobby and up the central spine of the building. A huge switchback staircase floats up to the galleries.
Twenty years…