If ambiguity was something that could be seen or touched, it might have a tangible yet enigmatic effect. Perhaps it would be like a fragile lantern lit from within, neither solid nor translucent, with angles of light taking shape through sudden rips of fabric. Or perhaps it would be a metallic cube hovering over the ground like an imbalanced weight, yet with a surface as seemingly delicate as crumpled paper. Or perhaps it would be a cold glass entrance with ice rock chandeliers, where luscious, decorative folds in white walls peek through. Maybe, in short, ambiguity would take the shape of the new Walker Art Center’s expansion. “More than a museum” is the catchphrase for this new Walker as it unveils its expanded size and reconceived programming. The Walker Art Center, located in Minneapolis, Minnesota, is already recognized internationally as a singular model for multidisciplinary arts organizations and as a national leader in innovative approaches to audience engagement. Adjacent to the Walker is the Minneapolis Sculpture Garden, one of the nation’s largest urban sculpture parks. In the words of Walker Director Kathy Halbreich, the new Walker that has now reopened after a year of construction is “an institutional space that...