In “Twyla Now,” a program of works featuring ballet stars and a youthful ensemble at New York City Center, Tharp merges the past with the present.In “Twyla Now,” a program of works featuring ballet stars and a youthful ensemble at New York City Center, Tharp merges the past with the present.Read MoreDancing, New York City Center Theater, Tharp, Twyla, Fairchild, Robert, Mearns, Sara, Baryshnikov, Mikhail, Twyla Now (Dance (Non-Ballet))