In the hanging sculptures of Alexander Calder, who died in 1976, three dimensions are joined by a fourth—time, that mystery. These works teeter in airy equilibrium, always on the fine edge of invisible forces. Calder’s brand of kinetic art revolutionized the static nature of sculpture, and artistic heirs took inspiration from his delicate mobiles. This year, on the 50th anniversary of his death, the artist is having a moment. Calder Gardens just opened in his birthplace of Philadelphia, and the Whitney Museum of American Art recently celebrated the centennial of his famous miniature installation Calder’s Circus, presenting the playful wire performers alongside related drawings, sculptures, and archival material. Now, 300 works by Calder are coming to the Fondation Louis Vuitton for a career-spanning retrospective. —Elena Clavarino