As a student at Yale, Fred Sandback struggled with sculpture until George Sugarmann told him "if you are so sick of the parts, why not just make a line with a ball of string and be done with it." For the rest of his career, Sandback used taut and resonant strings to sculpt space and light. Ephemeral and site-specific, his Minimalist sculptures, familiar to visitors to Dia: Beacon among other museums, use colorful acrylic yarn strung between the ceiling...