There is a new drama in the literary world and, surprisingly, Natalie Portman is at the center. It all started with Life of M, Rachel Cusk’s new novel, whose fictional protagonist has so many similarities with Black Swan’s actress that the Internet began to wonder about the inevitable: is it really inspired by her? The novel, which is published on August 25, follows a writer who tries to build the biography of “M,” a famous actress she knows per…