In a 1994 work titled Mom and Dad, the photographer Janine Antoni took three photos of her parents lovingly posed together. In the first, with help from prosthetics, her mother is made up to look like her dad; in the second, they swap identities; in the third, her father looks like her mother’s twin. These iterations of her parents, presented side by side, call into question the fixity of their gendered roles. Antoni’s triptych is on view in the exhibition “The Double,” which explores the motif of duplicates and identity in more than 120 paintings, sculptures, videos, and photographs from the last century. Ninety artists are featured, including Diane Arbus, Marcel Duchamp, Frank Stella, and Andy Warhol. —Jensen Davis